0001171843-22-001460 | 10-K | XBRL Viewer | Biocryst Pharmaceuticals INC

Consolidated Statements of Stockholders' Equity (Deficit) (Parentheticals) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Common Stock [Member]
Exercise of stock options, shares (in shares)	510	283
Employee stock purchase plan sales, shares (in shares)	246	115
Employee stock purchase plan sales, shares (in shares)	246	115
Issuance of common stock, shares (in shares)	22,044	43,621
Warrants issued (in shares)	3,511	11,765

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained Earnings [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (Accounting Standards Update 2014-09 [Member]) at Dec. 31, 2018	$ 238	$ 238
Balance at Dec. 31, 2018			$ 1,101	$ 780,400	$ (297)	$ (731,969)	$ 49,235
Net loss						(108,897)	(108,897)
Other comprehensive income (loss)					336		336
Exercise of stock options, net			3	832			835
Employee stock purchase plan			1	403			404
Issuance of common stock, net			436	58,064			58,500
Issuance of pre-funded warrants				19,882			19,882
Stock-based compensation expense				17,719			17,719
Balance at Dec. 31, 2019			1,541	877,300	39	(840,628)	38,252
Net loss						(182,814)	(182,814)
Other comprehensive income (loss)					(36)		(36)
Exercise of stock options, net			5	1,809			1,814
Employee stock purchase plan			3	629			632
Issuance of common stock, net			220	93,059			93,279
Issuance of pre-funded warrants				14,817			14,817
Stock-based compensation expense				14,794			14,794
Balance at Dec. 31, 2020			1,769	1,002,408	3	(1,023,442)	(19,262)
Net loss						(184,062)	(184,062)
Other comprehensive income (loss)					174		174
Exercise of stock options, net			33	13,772			13,805
Employee stock purchase plan			3	1,986			1,989
Issuance of common stock, net			38	45,692			45,730
Stock-based compensation expense				34,640			34,640
Balance at Dec. 31, 2021			$ 1,843	$ 1,098,498	$ 177	$ (1,207,504)	$ (106,986)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Note 4 - Trade Receivables (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Receivables from Collaborations [Table Text Block]

	December 31, 2021
	Billed		Unbilled		Total
U.S. Department of Health and Human Services, net	$	5	$	1,670	$	1,675
Royalty receivables from partners		305		−		305
Total receivables from collaborators	$	310	$	1,670	$	1,980

	December 31, 2020
	Billed		Unbilled		Total
U.S. Department of Health and Human Services, net	$	−	$	5,402	$	5,402
Royalty receivables from partners		2,816		25		2,841
Total receivables from collaborators	$	2,816	$	5,427	$	8,243

Note 11 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands					12 Months Ended
	Nov. 19, 2021	Jun. 01, 2020	Nov. 21, 2019	Nov. 18, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 17, 2021	Apr. 24, 2020
Stock Issued During Period, Shares, New Issues (in shares)		22,044		43,621	3,846	22,044	43,621
Shares Issued, Price Per Share (in dollars per share)		$ 4.50	$ 1.69	$ 1.45
Proceeds from Issuance of Common Stock				$ 58,500	$ 50,000	$ 93,279	$ 58,500
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			11,765
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 0.01
Proceeds from Issuance of Warrants			$ 19,882			$ 14,817	$ 19,882
Maximum Aggregate Offering Price									$ 500,000
Proceeds from Issuance or Sale of Equity, Total		$ 108,096,000
Common Stock Purchase Agreement with RPI [Member]
Stock Issued During Period, Shares, New Issues (in shares)	3,846,154
Shares Issued, Price Per Share (in dollars per share)	$ 13.00							$ 13.00
Proceeds from Issuance of Common Stock	$ 50,000
Shares Issued, Price Per Share, Premium (in dollars per share)								1.11
Shares Issued, Price Per Share, Closing Price (in dollars per share)								$ 11.89
Shares Issued, Common Stock, Premium								$ 4,269
Warrants Issued in Public Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		3,511
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 0.01
Class of Warrant or Right, Warrants Issued, Price Per Warrant (in dollars per share)		$ 4.49

Note 7 - Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Accrued Liabilities [Table Text Block]

	December 31,
	2021		2020
Compensation and benefits	$	20,674	$	11,030
Development costs		30,215		15,150
Revenue-related reserves for discounts and allowances		5,957		2
Royalties payable		4,426		−
Inventory		3,793		2,453
Professional fees		1,305		333
Duties and taxes		2,622		80
Other		3,678		4,894
Total accrued expenses	$	72,670	$	33,942

Note 5 - Inventory - Summary of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Raw materials	$ 5,658	$ 206
Work-in-process	9,669	2,555
Finished goods	709	4,548
Total inventory	16,036	7,309
Reserves	(245)	(270)
Total inventory, net	$ 15,791	$ 7,039

Note 2 - Revenue (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Disaggregation of Revenue [Table Text Block]

	2021			2020		2019
Product sales, net:
ORLADEYO	$	121,865		$	133	$	−
RAPIVAB		7,231			483		13,864
Peramivir		7,254			2,685		3,669
Total product sales, net		136,350			3,301		17,533
Royalty revenue		(100	)		3,381		6,303
Milestone revenue		15,000			−		−
Collaborative and other research and development revenues:
U.S. Department of Health and Human Services		5,920			9,231		4,898
Torii Pharmaceutical Co., Ltd.		−			1,899		20,101
Total collaborative and other research and development revenues		5,920			11,130		24,999
Total revenues	$	157,170		$	17,812	$	48,835

Note 4 - Trade Receivables (Details Textual) - Trade Accounts Receivable [Member] - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounts Receivable, after Allowance for Credit Loss, Total	$ 0	$ 0
ORLADEYO [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	27,384	149
RAPIVAB [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	49	254
Green Cross Corporation [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	$ 701	$ 0

Note 2 - Revenue - Summary of Revenues (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 05, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues		$ 157,170	$ 17,812	$ 48,835
Torii Pharmaceutical Co. [Member]
Revenues	$ 22,000
Product [Member]
Revenues		136,350	3,301	17,533
Product [Member] \| ORLADEYO [Member]
Revenues		121,865	133
Product [Member] \| RAPIVAB [Member]
Revenues		7,231	483	13,864
Product [Member] \| PERAMIVIR [Member]
Revenues		7,254	2,685	3,669
Royalty [Member]
Revenues		(100)	3,381	6,303
Milestone [Member]
Revenues		15,000
Collaborative and Other Research and Development [Member]
Revenues		5,920	11,130	24,999
Collaborative and Other Research and Development [Member] \| US Department of Health and Human Services [Member]
Revenues		$ 5,920	9,231	4,898
Collaborative and Other Research and Development [Member] \| Torii Pharmaceutical Co. [Member]
Revenues			$ 1,899	$ 20,101

Note 3 - Investments

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Investments and Other Noncurrent Assets [Text Block]

Note 3 - Investments

The following tables summarize the fair value of the Company’s investments by type. The estimated fair values of the Company’s fixed income investments are classified as Level 2 in the fair value hierarchy as defined in U.S. GAAP. These valuations are based on observable direct and indirect inputs, primarily quoted prices of similar, but not identical, instruments in active markets or quoted prices for identical or similar instruments in markets that are not active. These fair values are obtained from independent pricing services which utilize Level 2 inputs.

	December 31, 2021
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	4,043	$	17	$	-	$	(7	)	$	4,053
Corporate debt securities		4,294		40		-		(5	)		4,329
Certificates of deposit		1,652		8		-		(1	)		1,659
Total Investments	$	9.989	$	65	$	-	$	(13	)	$	10,041

	December 31, 2020
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	24,986	$	14	$	3	$	(3	)	$	25,000
Certificates of deposit		3,225		11		3		−			3,239
Total Investments	$	28,211	$	25	$	6	$	(3	)	$	28,239

The following table summarizes the scheduled maturity for the Company’s investments at December 31, 2021 and 2020.

	2021		2020
Maturing in one year or less	$	3,212	$	28,239
Maturing after one year through two years		6,829		−
Total investments	$	10,041	$	28,239

Note 10 - Lease Obligations (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating Lease, Weighted Average Remaining Lease Term (Year)	9 years 2 months 12 days
Operating Lease, Weighted Average Discount Rate, Percent	11.20%
Operating Lease, Expense	$ 1,795	$ 1,754
Operating Lease, Right-of-Use Asset, Accumulated Amortization	2,626	2,641
Operating Lease, Payments	$ 1,615	$ 1,696
Minimum [Member]
Lessee, Operating Lease, Term of Contract (Year)	1 year
Maximum [Member]
Lessee, Operating Lease, Term of Contract (Year)	5 years

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (184,062)	$ (182,814)	$ (108,897)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	777	748	724
Stock-based compensation expense	34,640	14,794	17,719
Non-cash interest expense on royalty financing obligations and secured term loan and amortization of debt issuance costs	54,204	3,325	1,278
Amortization of premium/discount on investments	(2)	121	117
Change in fair value of foreign currency derivative		632	347
(Gain) loss on extinguishment of debt	(55,838)	2,011
(Gain) loss on extinguishment of debt		1,211
Changes in operating assets and liabilities:
Receivables	(20,817)	13,903	(17,853)
Inventory	(8,767)	(7,039)	1,649
Prepaid expenses and other assets	(7,155)	(2,140)	(1,364)
Accounts payable and accrued expenses	39,412	17,355	11,741
Interest payable	4,168	6,766	3,056
Deferred revenue	1,283	(1,970)	1,899
Net cash used in operating activities	(142,157)	(135,108)	(89,584)
Cash flows from investing activities:
Acquisition of property and equipment	(2,385)	(514)	(343)
Purchases of investments	(10,012)	(49,818)	(3,018)
Sales and maturities of investments	28,201	43,476	81,295
Net cash provided by (used in) investing activities	15,804	(6,856)	77,934
Cash flows from financing activities:
Sale of common stock, net	50,000	93,279	58,500
Sale of pre-funded warrants		14,817	19,882
Net proceeds from common stock issued under stock-based compensation plans	15,794	2,446	1,239
Proceeds from senior credit facility			19,477
Payment of senior credit facility		(52,420)
Net proceeds from secured term loan		119,867
Net proceeds from royalty financing obligations	293,874	122,600
Net cash provided by financing activities	359,668	300,589	99,098
Effects of exchange rates on cash, cash equivalents and restricted cash	71
Increase in cash, cash equivalents and restricted cash	233,386	158,625	87,448
Cash, cash equivalents and restricted cash at beginning of year	274,348	115,723	28,275
Cash, cash equivalents and restricted cash at end of year	$ 507,734	$ 274,348	$ 115,723

Note 1 - Significant Accounting Policies and Concentrations of Risk (Details Textual) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Cash Provided by (Used in) Operating Activities, Total		$ (142,157)	$ (135,108)	$ (89,584)
Net Cash Provided by (Used in) Financing Activities, Total		359,668	300,589	99,098
Restricted Cash and Cash Equivalents, Current, Total	$ 2,221	3,345	2,221
Advertising Expense		5,705	6,567	0
Interest Expense, Debt, Total		59,294	14,501	11,892
Amortization of Debt Financing Costs and Original Issue Discounts		$ 531	$ 1,217	$ 1,278
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)		26,034	14,957	2,805
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax		$ 1	$ 1
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, Loss on Derivative			632	$ 347
Derivative, Gain on Derivative			662	$ 863
Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)		3 years
Laboratory Equipment, Office Equipment and Software [Member]
Property, Plant and Equipment, Useful Life (Year)		5 years
Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life (Year)		7 years
Royalty Receivable [Member]
Restricted Cash and Cash Equivalents, Current, Total	796	$ 1,924	796
Collateral for Credit [Member]
Restricted Cash and Cash Equivalents, Current, Total	1,425	$ 1,421	1,425
Maximum [Member]
Maturity Period of High Quality Marketable Securities (Year)		3 years
Average Maturity Period of High Quality Marketable Securities (Month)		12 months
Maturity Period of Short Term Investment (Month)		12 months
Minimum [Member]
Long-term Investment Maturity, Minimum (Year)		12 years
Previously Reported [Member]
Net Cash Provided by (Used in) Operating Activities, Total			(137,216)
Net Cash Provided by (Used in) Financing Activities, Total			302,697
Senior Credit Facility [Member] \| MidCap Financial Services, LLC [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 75,000
Write off of Deferred Debt Issuance Cost	$ 1,211		$ 1,211

Note 12 - Stock-based Compensation - Number of Stock Option Awards Exercisable and their Weighted Average Exercise Price (Details)	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Upper Exercise Price Range (in dollars per share)	$ 18
Outstanding Number (in shares) \| shares	33,093
Outstanding Weighted Average Remaining Life (Year)	7 years 6 months
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 7.68
Exercisable Number (in shares) \| shares	15,561
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 6.34
Exercise Price Range 01 [Member]
Upper Exercise Price Range (in dollars per share)	$ 3
Outstanding Number (in shares) \| shares	1,874
Outstanding Weighted Average Remaining Life (Year)	5 years 10 months 24 days
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 2.30
Exercisable Number (in shares) \| shares	1,158
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 2.12
Exercise Price Range 02 [Member]
Upper Exercise Price Range (in dollars per share)	$ 6
Outstanding Number (in shares) \| shares	10,190
Outstanding Weighted Average Remaining Life (Year)	6 years 6 months
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 4.22
Exercisable Number (in shares) \| shares	7,317
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 4.41
Exercise Price Range 03 [Member]
Upper Exercise Price Range (in dollars per share)	$ 9
Outstanding Number (in shares) \| shares	10,599
Outstanding Weighted Average Remaining Life (Year)	8 years 2 months 12 days
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 7.89
Exercisable Number (in shares) \| shares	4,317
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 7.56
Exercise Price Range 04 [Member]
Upper Exercise Price Range (in dollars per share)	$ 12
Outstanding Number (in shares) \| shares	8,228
Outstanding Weighted Average Remaining Life (Year)	8 years 1 month 6 days
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 11.14
Exercisable Number (in shares) \| shares	2,120
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 10.86
Exercise Price Range 05 [Member]
Upper Exercise Price Range (in dollars per share)	$ 15
Outstanding Number (in shares) \| shares	1,291
Outstanding Weighted Average Remaining Life (Year)	6 years 9 months 18 days
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 13.10
Exercisable Number (in shares) \| shares	535
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 12.31
Exercise Price Range 06 [Member]
Upper Exercise Price Range (in dollars per share)	$ 18
Outstanding Number (in shares) \| shares	911
Outstanding Weighted Average Remaining Life (Year)	9 years
Outstanding Weighted Average Exercise Price (in dollars per share)	$ 15.95
Exercisable Number (in shares) \| shares	114
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 15.56

Note 5 - Inventory (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Inventory, Current [Table Text Block]

	December 31,
	2021			2020
Raw materials	$	5,658		$	206
Work-in-process		9,669			2,555
Finished goods		709			4,548
Total inventory	$	16,036		$	7,309
Reserves		(245	)		(270	)
Total inventory, net	$	15,791		$	7,039

Significant Accounting Policies (Policies)	12 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Description of Company [Policy Text Block]	*The Company* BioCryst Pharmaceuticals, Inc. (the “Company”) is a commercial-stage biotechnology company that discovers novel, oral, small-molecule medicines. The Company focuses on the treatment of rare diseases in which significant unmet medical needs exist and an enzyme plays the key role in the biological pathway of the disease. The Company was founded in 1986 and incorporated in Delaware in 1991, and its headquarters is located in Durham, North Carolina. The Company integrates the disciplines of biology, crystallography, medicinal chemistry and computer modeling to discover and develop small molecule pharmaceuticals through the process known as structure-guided drug design. The Company’s marketed products include oral, once-daily ORLADEYO® for the prevention of hereditary angioedema (“HAE”) attacks and RAPIVAB® (peramivir injection) for the treatment of acute uncomplicated influenza in the United States. ORLADEYO received regulatory approval in the United States in December 2020. During 2021, ORLADEYO received regulatory approvals in the European Union, Japan, the United Arab Emirates and the United Kingdom. The Company is commercializing ORLADEYO in each of these territories directly or through distributors, except in Japan where Torii Pharmaceuticals Co., Ltd. (“Torii”), the Company’s collaborative partner, has the exclusive right to commercialize ORLADEYO for the prevention of HAE attacks in exchange for certain milestone and royalty payments to us. In addition to its approval in the United States, peramivir injection has received regulatory approvals in Canada, Australia, Japan, Taiwan and Korea. Based on the Company’s expectations for revenue, operating expenses, and the additional $75 million available to the Company under its existing credit facility, the Company believes its financial resources available at December 31, 2021 will be sufficient to fund its operations for at least the next 12 months. The Company has sustained operating losses for the majority of its corporate history and expects that its 2022 expenses will exceed its 2022 revenues. The Company expects to continue to incur operating losses and negative cash flows until revenues reach a level sufficient to support ongoing operations. The Company’s liquidity needs will be largely determined by the success of operations in regard to the successful commercialization of its products and the progression of its product candidates in the future. The Company regularly evaluates other opportunities to fund future operations, including: (1) securing or increasing U.S. Government funding of its programs, including obtaining procurement contracts; (2) out-licensing rights to certain of its products or product candidates, pursuant to which the Company would receive cash milestone payments; (3) raising additional capital through equity or debt financings or from other sources, including royalty or other monetization transactions; (4) obtaining additional product candidate regulatory approvals, which would generate revenue, milestone payments and cash flow; (5) reducing spending on one or more research and development programs, including by discontinuing development; and/or (6) restructuring operations to change its overhead structure. The Company may issue securities, including common stock, preferred stock, depositary shares, purchase contracts, warrants, debt securities and units, through private placement transactions or registered public offerings in the future. The Company’s future liquidity needs, and ability to address those needs, will largely be determined by the success of its products and product candidates, timing, scope and magnitude of its commercial expenses and key development and regulatory events and its decisions in the future.
Basis of Accounting, Policy [Policy Text Block]	*Basis of Presentation* The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances among the consolidated entities have been eliminated from the consolidated financial statements. The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). Such consolidated financial statements reflect all adjustments that are, in management’s opinion, necessary to present fairly, in all material respects, the Company’s consolidated financial position, results of operations, and cash flows. There were no adjustments other than normal recurring adjustments.
Reclassifications [Policy Text Block]	*Reclassifications/Revisions* The Company has reclassified certain non-cash expense amounts on the Consolidated Statement of Cash Flows for the year ended December 31, 2020, to conform with the current year presentation. Additionally, the Company revised its Consolidated Statement of Cash Flows for the year ended December 31, 2020 to reflect an immaterial correction whereby net cash used in operating activities was revised from $(137,216) to $(135,108) and net cash provided by financing activities was revised from $302,697 to $300,589. The reclassifications and correction had no effect on net cash flows and no impact on the Consolidated Balance Sheet, Consolidated Statement of Comprehensive Loss, Consolidated Statement of Stockholders’ Equity (Deficit), or the net loss or loss per share for the year ended December 31, 2020.
Use of Estimates, Policy [Policy Text Block]	*Use of Estimates* The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. The most significant estimates in the Company’s consolidated financial statements relate to the valuation of stock options, the ORLADEYO royalty financing obligations and the valuation allowance for deferred tax assets resulting from net operating losses. These estimates are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates.
Revenue [Policy Text Block]	*Revenue Recognition* Pursuant to Accounting Standards Codification (“ASC”) Topic 606, the Company recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, Topic 606 includes provisions within a five step model that includes i) identifying the contract with a customer, ii) identifying the performance obligations in the contract, iii) determining the transaction price, iv) allocating the transaction price to the performance obligations, and v) recognizing revenue when, or as, an entity satisfies a performance obligation. At contract inception, the Company identifies the goods or services promised within each contract, assesses whether each promised good or service is distinct and determines those that are performance obligations. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied. Product Sales, Net The Company’s principal sources of product sales are sales of ORLADEYO, which the Company began shipping to patients in December 2020, sales of peramivir to the Company’s licensing partners and sales of RAPIVAB to the U.S. Department of Health and Human Services under the Company’s procurement contract. In the United States, the Company ships ORLADEYO directly to patients through a single specialty pharmacy, which is considered its customer. In the European Union, United Kingdom and elsewhere, the Company sells ORLADEYO to specialty distributors as well as hospitals and pharmacies, which collectively are considered its customers. The Company recognizes revenue for sales when its customers obtain control of the product, which generally occurs upon delivery. For ORLADEYO, the Company classifies payments to its specialty pharmacy customer for certain services provided by its customer as selling, general and administrative expenses to the extent such services provided are determined to be distinct from the sale of its product. Net revenue from sales of ORLADEYO is recorded at net selling price (transaction price), which includes estimates of variable consideration for which reserves are established for (i) estimated government rebates, such as Medicaid and Medicare Part D reimbursements, and estimated managed care rebates, (ii) estimated chargebacks, (iii) estimated costs of co-payment assistance programs and (iv) product returns. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable or as a current liability. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the applicable contract. The amount of variable consideration included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company's estimates. If actual results in the future vary from estimates, the Company adjusts these estimates, which would affect net product revenue and earnings in the period such variances become known. Government and Managed Care Rebates. The Company contracts with government agencies and managed care organizations or, collectively, third-party payors, so that ORLADEYO will be eligible for purchase by, or partial or full reimbursement from, such third-party payors. The Company estimates the rebates it will provide to third-party payors and deducts these estimated amounts from total gross product revenues at the time the revenues are recognized. These reserves are recorded in the same period in which the revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability. The Company estimates the rebates that it will provide to third-party payors based upon (i) the Company's contracts with these third-party payors, (ii) the government mandated discounts applicable to government-funded programs, (iii) a range of possible outcomes that are probability-weighted for the estimated payor mix, and (iv) product distribution information obtained from the Company's specialty pharmacy. Chargebacks. Chargebacks are discounts that occur when certain contracted customers, pharmacy benefit managers, insurance companies and government programs purchase directly from the Company’s specialty pharmacy. These customers purchase the Company’s product under contracts negotiated between them and the Company’s specialty pharmacy. The specialty pharmacy, in turn, charges back to the Company the difference between the price the specialty pharmacy paid and the negotiated price paid by the contracted customers, which may be higher or lower than the specialty pharmacy’s purchase price from the Company. The Company estimates chargebacks and adjusts gross product revenues and accounts receivable based on the estimates at the time revenues are recognized. Co-payment assistance and patient assistance programs. Patients who have commercial insurance and meet certain eligibility requirements may receive co-payment assistance. Based upon the terms of the program and co-payment assistance utilization reports received from the specialty pharmacy, the Company is able to estimate the co-payment assistance amounts, which are recorded in the same period in which the related revenue is recognized, resulting in a reduction of product revenue. The Company also offers a patient assistance program that provides free drug product, for a limited period of time, to allow a patient’s insurance coverage to be established. Based on patient assistance program utilization reports provided by the specialty pharmacy, the Company records gross revenue of the product provided and a full reduction of the revenue amount for the free drug discount. Product returns. The Company does not provide contractual return rights to its customer, except in instances where the product is damaged or defective. Non-acceptance by the patient of shipped drug product by the specialty pharmacy is reflected as a reversal of sales in the period in which the sales were originally recorded. Reserves for estimated non-acceptances by patients are recorded as a reduction of revenue in the period that the related revenue is recognized, as well as a reduction to accounts receivable. Estimates of non-acceptance are based on quantitative information provided by the specialty pharmacy. Collaborative and Other Research and Development Arrangements and Royalties The Company has collaboration and license agreements with a number of third parties, as well as research and development agreements with certain government entities. The Company’s primary sources of revenue from these collaborative and other research and development arrangements are license, service and royalty revenues. Revenue from license fees, royalty payments, milestone payments, and research and development fees are recognized as revenue when the earnings process is complete and the Company has no further continuing performance obligations or the Company has completed the performance obligations under the terms of the agreement. Arrangements that involve the delivery of more than one performance obligation are initially evaluated as to whether the intellectual property licenses granted by the Company represent distinct performance obligations. If they are determined to be distinct, the value of the intellectual property licenses would be recognized up front while the research and development service fees would be recognized as the performance obligations are satisfied. For performance obligations based on services performed, the Company measures progress using an input method based on the effort it expends or costs it incurs toward the satisfaction of the performance obligation in relation to the total estimated effort or costs. Variable consideration is assessed at each reporting period as to whether it is not subject to significant future reversal and, therefore, should be included in the transaction price at the inception of the contract. If a contract includes a fixed or minimum amount of research and development support, this also would be included in the transaction price. Changes to collaborations, such as the extensions of the research term or increasing the number of targets or technology covered under an existing agreement, are assessed for whether they represent a modification or should be accounted for as a new contract. For contracts with multiple performance obligations, revenue is allocated to each performance obligation based on its relative standalone selling price. Standalone selling prices are based on observable prices at which the Company separately sells the products or services. If a standalone selling price is not directly observable, then the Company estimates the standalone selling price using either an adjusted market assessment approach or an expected cost plus margin approach, representing the amount that the Company believes the market is willing to pay for the product or service. Analyzing the arrangement to identify performance obligations requires the use of judgment, and each may be an obligation to deliver services, a right or license to use an asset, or another performance obligation. Milestone payments are recognized as licensing revenue upon the achievement of specified milestones if (i) the milestone is substantive in nature and the achievement of the milestone was not probable at the inception of the agreement; and (ii) the Company has a right to payment. Any milestone payments received prior to satisfying these revenue recognition criteria are recorded as deferred revenue. Reimbursements received for direct out-of-pocket expenses related to research and development costs are recorded as revenue in the Consolidated Statements of Comprehensive Loss rather than as a reduction in expenses. Under the Company’s contracts with the Biomedical Advanced Research and Development Authority within the United States Department of Health and Human Services (”BARDA/HHS”) and the National Institute of Allergy and Infectious Diseases (“NIAID/HHS”), revenue is recognized as reimbursable direct and indirect costs are incurred. Under certain of the Company’s license agreements, the Company receives royalty payments based upon its licensees’ net sales of covered products. Royalties are recognized at the later of when (i) the subsequent sale or usage occurs, or (ii) the performance obligation to which some or all of the sales-based or usage-based royalty has been satisfied.
Cash and Cash Equivalents, Policy [Policy Text Block]	*Cash and Cash Equivalents* The Company generally considers cash equivalents to be all cash held in commercial checking accounts, certificates of deposit, money market accounts or investments in debt instruments with maturities of three months or less at the time of purchase. The carrying value of cash and cash equivalents approximates fair value due to the short-term nature of these items.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	*Restricted Cash* Restricted cash as of December 31, 2021 and 2020 reflects $1,924 and $796, respectively, in royalty revenue paid by Shionogi & Co., Ltd. (“Shionogi”) designated for interest on the PhaRMA Notes (defined in Note 8) and $1,421 and $1,425, respectively, the Company is required to maintain as collateral for a letter of credit associated with the lease execution and build-out of its new Birmingham research facilities.
Investment, Policy [Policy Text Block]	*Investments* The Company invests in high credit quality investments in accordance with its investment policy, which is designed to minimize the possibility of loss. The objective of the Company’s investment policy is to ensure the safety and preservation of invested funds, as well as maintaining liquidity sufficient to meet cash flow requirements. The Company places its excess cash with high credit quality financial institutions, commercial companies, and government agencies in order to limit the amount of its credit exposure. In accordance with its policy, the Company is able to invest in marketable debt securities that may consist of U.S. Government and government agency securities, money market and mutual fund investments, certificates of deposits, municipal and corporate notes and bonds, and commercial paper, among others. The Company’s investment policy requires it to purchase high-quality marketable securities with a maximum individual maturity of three years and requires an average portfolio maturity of no more than 12 months. Some of the securities the Company invests in may have market risk. This means that a change in prevailing interest rates may cause the principal amount of the investment to fluctuate. To minimize this risk, the Company schedules its investments with maturities that coincide with expected cash flow needs, thus avoiding the need to redeem an investment prior to its maturity date. Accordingly, the Company does not believe it has a material exposure to interest rate risk arising from its investments. Generally, the Company’s investments are not collateralized. The Company has not realized any significant losses from its investments. The Company classifies all of its investments as available-for-sale. Unrealized gains and losses on investments are recognized in comprehensive loss, unless an unrealized loss is considered to be other than temporary, in which case the unrealized loss is charged to operations. The Company periodically reviews its investments for other than temporary declines in fair value below cost basis and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company believes the individual unrealized losses represent temporary declines primarily resulting from interest rate changes. Realized gains and losses are reflected in interest and other income in the Consolidated Statements of Comprehensive Loss and are determined using the specific identification method with transactions recorded on a settlement date basis. Investments with original maturities at date of purchase beyond three months and which mature at or less than 12 months from the balance sheet date are classified as current. Investments with a maturity beyond 12 months from the balance sheet date are classified as long-term. At December 31, 2021, the Company believes that the cost of its investments is recoverable in all material respects.
Receivable [Policy Text Block]	*Trade Receivables* The majority of the Company’s trade receivables arise from product sales and primarily represent amounts due from our specialty pharmacy customer in the U.S. and other third-party distributors, hospitals and pharmacies in the European Union, United Kingdom and elsewhere and have standard payment terms that generally require payment within 30 to 90 days. Receivables from collaborations are recorded for amounts due to the Company related to reimbursable research and development costs from the U.S. Department of Health and Human Services, and royalty receivables from our partners, including Shionogi, Green Cross, and Torii. Monthly invoices are submitted to the U.S. Department of Health and Human Services related to reimbursable research and development costs. The Company is also entitled to monthly reimbursement of indirect costs based on rates stipulated in the underlying contract. The Company’s calculations of its indirect cost rates are subject to audit by the U.S. Government. The Company does not adjust its receivables for the effects of a significant financing component at contract inception if it expects to collect the receivables in one year or less from the time of sale. The Company provides reserves against trade receivables for estimated losses that may result from a customer's inability to pay. Receivables are evaluated to determine if any reserve or allowance should be recorded based on consideration of the current economic environment, expectations of future economic conditions, specific circumstances and the Company’s own historical collection experience. Amounts determined to be uncollectible are charged or written-off against the reserve.
Inventory, Policy [Policy Text Block]	*Inventory* The Company values its inventories at the lower of cost or estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials, labor, manufacturing overhead, and shipping and handling costs on a first-in, first-out (FIFO) basis. Raw materials and work-in-process include all inventory costs prior to packaging and labelling, including raw material, active product ingredient, and the drug product. Finished goods include packaged and labelled products. The Company’s inventories are subject to expiration dating. The Company regularly evaluates the carrying value of its inventories and provides valuation reserves for any estimated obsolete, short-dated or unmarketable inventories. In addition, the Company may experience spoilage of its raw materials and supplies. The Company’s determination that a valuation reserve might be required, in addition to the quantification of such reserve, requires it to utilize significant judgement. The Company expenses costs related to the production of inventories as research and development expenses in the period incurred until such time it is believed that future economic benefit is expected to be recognized, which generally is reliant upon receipt of regulatory approval. Upon regulatory approval, the Company capitalizes subsequent costs related to the production of inventories.
Property, Plant and Equipment, Policy [Policy Text Block]	*Property and Equipment* Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Computer equipment is depreciated over a life of three years. Laboratory equipment, office equipment, and software are depreciated over a life of five years. Furniture and fixtures are depreciated over a life of seven years. Leasehold improvements are amortized over their estimated useful lives or the expected lease term, whichever is less. In accordance with U.S. GAAP, the Company periodically reviews its property and equipment for impairment when events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written down to their estimated fair values. Property and equipment to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.
Accrued Expenses [Policy Text Block]	*Accrued Expenses* The Company generally enters into contractual agreements with third-party vendors who provide research and development, manufacturing, distribution, and other services in the ordinary course of business. Some of these contracts are subject to milestone-based invoicing, and services are completed over an extended period of time. The Company records liabilities under these contractual commitments when it determines an obligation has been incurred, regardless of the timing of the invoice. This process involves reviewing open contracts and purchase orders, communicating with applicable Company personnel to identify services that have been performed on its behalf and estimating the level of service performed and the associated cost incurred for the service when the Company has not yet been invoiced or otherwise notified of actual cost. The majority of service providers invoice the Company monthly in arrears for services performed. The Company makes estimates of accrued expenses as of each balance sheet date in its financial statements based on the facts and circumstances. The Company periodically confirms the accuracy of its estimates with the service providers and makes adjustments if necessary. Examples of estimated accrued expenses include (i) fees paid to clinical research organizations (“CROs”) in connection with preclinical and toxicology studies and clinical trials; (ii) fees paid to investigative sites in connection with clinical trials; (iii) fees paid to contract manufacturers in connection with the production of the Company’s raw materials, drug substance, drug products, and product candidates; and (iv) professional fees. The Company bases its expenses related to clinical trials on its estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and CROs that conduct and manage clinical trials on the Company’s behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. Payments under some of these contracts depend on factors such as the successful enrollment of patients and the completion of clinical trial milestones. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. As of December 31, 2021 and December 31, 2020, the carrying value of accrued expenses approximates their fair value due to their short-term settlement.
Cost of Goods and Service [Policy Text Block]	*Cost of Product Sales* Cost of product sales includes the cost of producing and distributing inventories that are related to product revenue during the respective period, including freight. In addition, shipping and handling costs for product shipments are recorded as incurred. Finally, cost of product sales may also include costs related to excess or obsolete inventory adjustment charges.
Research and Development Expense, Policy [Policy Text Block]	*Research and Development Expenses* The Company’s research and development costs are charged to expense when incurred. Research and development expenses include all direct and indirect development costs related to the development of the Company’s portfolio of product candidates. Advance payments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. Such amounts are recognized as expense when the related goods are delivered or the related services are performed. Research and development expenses include, among other items, personnel costs, including salaries and benefits, manufacturing costs, clinical, regulatory, and toxicology services performed by CROs, materials and supplies, and overhead allocations consisting of various administrative and facilities related costs. Most of the Company’s manufacturing and clinical and preclinical studies are performed by third-party CROs. Costs for studies performed by CROs are accrued by the Company over the service periods specified in the contracts, and estimates are adjusted, if required, based upon the Company’s ongoing review of the level of services actually performed. Additionally, the Company has license agreements with third parties, such as Albert Einstein College of Medicine of Yeshiva University (“AECOM”), Industrial Research, Ltd. (“IRL”), and the University of Alabama at Birmingham (“UAB”), which require fees related to sublicense agreements or maintenance fees. The Company expenses sublicense payments as incurred unless they are related to revenues that have been deferred, in which case the expenses are deferred and recognized over the related revenue recognition period. The Company expenses maintenance payments as incurred. Deferred collaboration expenses represent sub-license payments, paid to the Company’s academic partners upon receipt of consideration from various commercial partners, and other consideration paid to the Company’s academic partners for modification to existing license agreements. These deferred expenses would not have been incurred without receipt of such payments or modifications from the Company’s commercial partners and are being expensed in proportion to the related revenue being recognized. The Company believes that this accounting treatment appropriately matches expenses with the associated revenue.
Selling, General and Administrative Expenses, Policy [Policy Text Block]	*Selling, General and Administrative Expenses* Selling, general and administrative expense is primarily comprised of compensation and benefits associated with sales and marketing, finance, human resources, legal, information technology and other administrative personnel. Additionally, selling, general and administrative expenses are comprised of market research, marketing, advertising and legal expenses, including patent costs, licenses and other general and administrative costs, Advertising expenses related to ORLADEYO were $5,705 and $6,567 for the years ended December 31, 2021 and 2020, respectively. The Company did not incur advertising and product promotion expenses in 2019. The Company seeks patent protection on all internally developed processes and products. All patent related costs are expensed to selling, general and administrative expenses when incurred as recoverability of such expenditures is uncertain.
Lessee, Leases [Policy Text Block]	*Leases* The Company leases certain assets under operating leases, which primarily consisted of real estate leases, laboratory equipment leases and office equipment leases as of December 31, 2021. The Company accounts for lease obligations in accordance with ASU 2016-02: Leases (Topic 842), which requires a lessee to recognize a right-of-use asset and a lease liability on its balance sheet for most operating leases. Certain of the Company’s operating leases provide for renewal options, which can vary by lease. The right-of-use asset and lease liabilities on the Company’s Consolidated Balance Sheet represent payments over the lease term, which includes renewal options for certain real estate leases that we are likely to exercise. As part of the Company’s assessment of the lease term, the Company elected the hindsight practical expedient, which allows companies to use current knowledge and expectations when determining the likelihood to extend lease options. Certain operating leases include rent escalation provisions, which the Company recognizes as expense on a straight-line basis. Lease expense for leases with an initial term of twelve months or less was not material. The discount rate used in the calculation of the Company’s right-of-use asset and lease liability was determined based on the stated rate within each contract when available, or the Company’s collateralized borrowing rate from lending institutions. The Company has not made any residual value guarantees related to its operating leases; therefore, the Company has no corresponding liability recorded on its Consolidated Balance Sheets.
Share-based Payment Arrangement [Policy Text Block]	*Stock-Based Compensation* All share-based payments, including grants of stock option awards and restricted stock unit awards, are recognized in the Company’s Consolidated Statements of Comprehensive Loss based on their fair values. The fair value of stock option awards is estimated using the Black-Scholes option pricing model. The fair value of restricted stock unit awards is based on the grant date closing price of the common stock. Stock-based compensation cost is recognized as expense on a straight-line basis over the requisite service period of the award. In addition, we have outstanding performance-based stock options for which no compensation expense is recognized until “performance” is deemed to have occurred.
Interest Expense and Royalty Financing Obligation [Policy Text Block]	*Interest Expense and Deferred Financing Costs* Interest expense for the years ended December 31, 2021, 2020 and 2019 was $59,294, $14,501 and $11,892, respectively, and primarily relates to the royalty financing obligations and PhaRMA Notes (Note 8), the secured term loan borrowing from the Credit Agreement and the senior credit facility (Note 9). Costs directly associated with the borrowings have been capitalized and are netted against the corresponding debt liabilities on the Consolidated Balance Sheets. These costs are being amortized to interest expense over the terms of the corresponding borrowings using the effective interest rate method. Amortization of deferred financing costs included in interest expense was $(531), $1,217 and $1,278 for the years ended December 31, 2021, 2020 and 2019, respectively. In December 2021, the PhaRMA Notes and associated accrued interest payable was written-off into other income as a debt extinguishment (Refer to Note 8, Non-Recourse Notes Payable – Debt Extinguishment for additional information regarding the debt extinguishment). In December 2020, the outstanding principal balance of the senior credit facility was repaid and related unamortized deferred financing costs and original issue discount of $1,211 were fully expensed as part of loss on debt extinguishment.
Interest Expense and Deferred Financing Costs [Policy Text Block]	*Interest Expense and Royalty Financing Obligations* The royalty financing obligations are eligible to be repaid based on royalties from net sales of ORLADEYO, BCX9930, and another earlier stage Factor D inhibitor. Interest expense is accrued using the effective interest rate method over the estimated period each of the related liabilities will be paid. This requires the Company to estimate the total amount of future royalty payments to be generated from product sales over the life of the agreement. The Company imputes interest on the carrying value of each of the royalty financing obligations and records interest expense using an imputed effective interest rate. The Company reassesses the expected royalty payments each reporting period and accounts for any changes through an adjustment to the effective interest rate on a prospective basis. The assumptions used in determining the expected repayment term of the debt and amortization period of the issuance costs requires that the Company make estimates that could impact the carrying value of each of the liabilities, as well as the periods over which associated issuance costs will be amortized. A significant increase or decrease in forecasted net sales could materially impact each of the liability balances, interest expense and the time periods for repayment.
Currency Hedge Agreement [Policy Text Block]	*Currency Hedge Agreement* In connection with the issuance by JPR Royalty Sub LLC of the PhaRMA Notes, the Company entered into a Currency Hedge Agreement to hedge certain risks associated with changes in the value of the Japanese yen relative to the U.S. dollar. The final tranche of the options under the Currency Hedge Agreement expired in November 2020. The Currency Hedge Agreement did not qualify for hedge accounting treatment; therefore mark-to-market adjustments were recognized in the Company’s Consolidated Statements of Comprehensive Loss. Cumulative mark-to-market adjustments for the years ended December 31, 2020 and 2019 resulted in losses of $632 and $347, respectively. Mark-to-market adjustments were determined by a third-party pricing model which uses quoted prices in markets that are not actively traded and for which significant inputs are observable directly or indirectly, representing Level 2 in the fair value hierarchy as defined by U.S. GAAP. In addition, realized currency exchange gains of $662 and $863 were recognized in 2020 and 2019, respectively, related to the exercise of a U.S. dollar/Japanese yen currency option under the Company’s foreign currency hedge.
Income Tax, Policy [Policy Text Block]	*Income Taxes* The liability method is used in the Company’s accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse.
Earnings Per Share, Policy [Policy Text Block]	*Net Loss Per Share* Net loss per share is based upon the weighted average number of common shares outstanding during the period. Diluted loss per share is equivalent to basic net loss per share for all periods presented herein because common equivalent shares from unexercised stock options, warrants and common shares expected to be issued under the Company’s equity compensation plans were anti-dilutive. The calculation of diluted earnings per share for the years ended December 31, 2021, 2020, and 2019 does not include 26,034, 14,957, and 2,805, respectively, of potential common shares as their impact would be anti-dilutive.
Comprehensive Income, Policy [Policy Text Block]	*Accumulated Other Comprehensive Income* Accumulated other comprehensive income is comprised of cumulative foreign currency translation adjustments and unrealized gains and losses on available-for-sale investments and is disclosed as a separate component of stockholders’ equity. Realized gain and loss amounts on available-for-sale investments are reclassified from accumulated other comprehensive loss and recorded as interest and other income on the Consolidated Statements of Comprehensive Loss. For both the years ended December 31, 2021 and 2020, realized gains of $1 were reclassified out of accumulated other comprehensive income.
Concentration of Market Risk [Policy Text Block]	*Significant Customers and Other Risks* Significant Customers The Company’s primary sources of revenue and cash flow are the sales of ORLADEYO to a specialty pharmacy, the reimbursement of galidesivir (formerly BCX4430) development expenses earned under cost-plus-fixed-fee contracts with BARDA/HHS and NIAID/HHS and sales of RAPIVAB (peramivir injection) under our procurement contract with the Assistant Secretary for Preparedness and Response within the United States Department of Health and Human Services. ORLADEYO is distributed through an arrangement with a single specialty pharmacy in the U.S. The specialty pharmacy subsequently sells ORLADEYO to its customers (pharmacy benefit managers, insurance companies, government programs and group purchasing organizations) and dispenses product to patients. The specialty pharmacy’s inability or unwillingness to continue these distribution activities could adversely impact the Company’s business, results of operations and financial condition. The Company relies on BARDA/HHS and NIAID/HHS to reimburse predominantly all of the development costs for its galidesivir program and stockpiling sales of RAPIVAB to HHS. Accordingly, reimbursement of these expenses represents a significant portion of the Company’s collaborative and other research and development revenues. Additionally, HHS is the primary customer for RABIVAB. The completion or termination of the NIAID/HHS and BARDA/HHS galidesivir contracts or the reduction or stoppage of purchases of RAPIVAB by HHS could adversely impact the Company’s business, results of operations and financial condition. Further, the Company’s drug development activities are performed by a limited group of third-party vendors. If any of these vendors were unable to perform its services, this could significantly impact the Company’s ability to complete its drug development activities. Risks from Third-Party Manufacturing and Distribution Concentration The Company relies on single source manufacturers for active pharmaceutical ingredient and finished drug product manufacturing of product candidates in development and on a single specialty pharmacy for distribution of approved drug product in the US. Delays in the manufacture or distribution of any product could adversely impact the commercial revenue and future procurement stockpiling of the Company’s product candidates. Credit Risk Cash equivalents and investments are financial instruments that potentially subject the Company to concentration of risk to the extent recorded on the Consolidated Balance Sheets. The Company deposits excess cash with major financial institutions in the United States. Balances may exceed the amount of insurance provided on such deposits. The Company believes it has established guidelines for investment of its excess cash relative to diversification and maturities that maintain safety and liquidity. To minimize the exposure due to adverse shifts in interest rates, the Company maintains a portfolio of investments with an average maturity of approximately 12 months or less. The Company’s receivables from sales of ORLADEYO are primarily due from one customer, resulting in a concentration of credit risk. Sales of ORLADEYO from the Company to the specialty pharmacy only occur once an order of product has been received by the specialty pharmacy from one of its customers, which include pharmacy benefit managers, insurance companies, government programs and group purchasing organizations. The majority of the Company’s receivables from collaborations are due from the U.S. Government, for which there is no assumed credit risk.
New Accounting Pronouncements, Policy [Policy Text Block]	*Recently Adopted Accounting Pronouncements* In December 2019, the FASB issued ASU No. 2019-12 (ASC Topic 740), Simplifying the Accounting for Income Taxes. ASU 2019-12 simplifies accounting for income taxes by removing certain exceptions to the general principles and clarifying existing guidance. This standard is effective for fiscal years, and interim periods within those years, beginning after December 15, 2020. The adoption of this standard did not have a material impact to the Company’s financial position, results of operations or cash flows. The Company has reviewed other new accounting pronouncements that were issued as of December 31, 2021 and does not believe that these pronouncements are either applicable to the Company, or that they will have a material impact on its financial position or results of operations.

Note 8 - Royalty Monetizations (Details Textual) - USD ($) $ in Thousands				12 Months Ended
	Nov. 19, 2021	Dec. 07, 2020	Mar. 09, 2011	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2021	Dec. 01, 2020
Proceeds from Issuance of Secured Debt					$ 119,867
Gain (Loss) on Extinguishment of Debt, Total				$ 55,838	$ (2,011)
RPI 2019 Intermediate Finance Trust [Member]
Shares Issued, Common Stock, Premium				4,269
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets		20.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $350,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories		8.75%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $350,000 and $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories		2.75%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories		0.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $150,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets		20.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $150,000 and $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets		10.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets		0.00%
RPI 2019 Intermediate Finance Trust [Member] \| BCX9930 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Global Annual Net Sales		1.00%
Royalty Purchase Agreement, Royalties, Maximum Tiered Profit Share Percentage on Permitted Sales in Other Markets	3.00%
RPI 2019 Intermediate Finance Trust [Member] \| BCX9930 [Member] \| Annual Net Sales Over $3 Billions [Member]
Royalty Purchase Agreement, Royalties, Annual Net Sales Payment Threshold	$ 3,000,000
RPI 2019 Intermediate Finance Trust [Member] \| Future Royalties Payable [Member]
Proceeds from Issuance of Debt		$ 125,000
Debt Issuance Costs, Net, Total				2,370
RPI 2021 and 2020 Intermediate Finance Trust [Member] \| Future Royalties Payable [Member]
Proceeds from Issuance of Debt	$ 150,000
The 2021 RPI Royalty Purchase Agreement [Member] \| Annual Net Sales Under $350,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	0.75%
The 2021 RPI Royalty Purchase Agreement [Member] \| Annual Net Sales Between $350,000 and $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	1.75%
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	0.00%
The 2021 RPI Royalty Purchase Agreement [Member] \| Annual Net Sales Under $150,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	3.00%
The 2021 RPI Royalty Purchase Agreement [Member] \| Annual Net Sales Between $150,000 and $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	2.00%
The 2021 RPI Royalty Purchase Agreement [Member] \| BCX9930 [Member] \| Annual Net Sales Under $1.5 Billion [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	3.00%
The 2021 RPI Royalty Purchase Agreement [Member] \| BCX9930 [Member] \| Annual Net Sales Between $1.5 and $3 Billions [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	2.00%
The 2021 RPI Royalty Purchase Agreement [Member] \| BCX9930 [Member] \| Annual Net Sales Over $3 Billions [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	0.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	20.00%
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	10.00%
Royalty Purchase Agreement, Royalties, Purchase Price, Amount	$ 150,000
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Minimum [Member]
Royalty Purchase Agreement, Royalties, Percentage of Purchase Price	142.50%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Maximum [Member]
Royalty Purchase Agreement, Royalties, Percentage of Purchase Price	155.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $350,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales	7.50%
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales, Based on Reduction in Sales	10.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $350,000 and $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales	6.00%
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales, Based on Reduction in Sales	3.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales	0.00%
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales, Based on Reduction in Sales	0.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $150,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	20.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $150,000 and $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	10.00%
OMERS Capital Markets [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	0.00%
PhaRMA Notes Member]
Private Placement of Senior Secured Notes			$ 30,000
Debt Instrument, Interest Rate, Stated Percentage			14.00%
Secured Debt, Total							$ 30,000
Interest Payable							$ 20,614
Gain (Loss) on Extinguishment of Debt, Total				$ 25,838
PhaRMA Notes Member] \| Fair Value, Inputs, Level 2 [Member]
Notes Payable, Fair Value Disclosure						$ 30,000
Royalty Monetization [Member]
Debt Instrument, Face Amount			$ 30,000
Proceeds from Issuance of Secured Debt			22,691
Transaction Costs			4,309
Interest Reserve			$ 3,000

Note 3 - Investment - Schedule of Maturity of Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Maturing in one year or less	$ 3,212	$ 28,239
Maturing after one year through two years	6,829
Total investments	$ 10,041	$ 28,239

Note 12 - Stock-based Compensation

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Share-based Payment Arrangement [Text Block]

Note 12 — Stock-Based Compensation

As of December 31, 2021, the Company had three stock-based employee compensation plans, the Amended and Restated Stock Incentive Plan (“Incentive Plan”), the Amended and Restated Inducement Equity Incentive Plan (“Inducement Plan”) and the Employee Stock Purchase Plan (“ESPP”). The Incentive Plan was most recently amended and restated on April 1, 2021 and approved by the Company’s stockholders on May 25, 2021. The Inducement Plan was adopted by the Board of Directors on April 24, 2019 and was most recently amended and restated by the Board of Directors on July 23, 2021. The ESPP was most recently amended and restated on April 1, 2021 and approved by the Company’s stockholders on May 25, 2021.

Stock-based compensation expense of $34,640 ($27,062 of expense related to the Incentive Plan, $6,055 of expense related to the Inducement Plan, $1,523 of expense related to the ESPP) was recognized during 2021, while $14,794 ($12,938 of expense related to the Incentive Plan, $1,494 of expense related to the Inducement Plan, $362 of expense related to the ESPP) was recognized during 2020 and $17,719 ($17,164 of expense related to the Incentive Plan, $323 of expense related to the Inducement Plan, $232 of expense related to the ESPP) was recognized during 2019.

The Company accounts for stock-based compensation in accordance with FASB authoritative guidance regarding share-based payments. Total stock-based compensation was allocated as follows:

	Years Ended December 31,
	2021		2020		2019
Research and development	$	20,179	$	10,222	$	13,977
Selling, general and administrative		14,461		4,572		3,742
Total stock-based compensation expense	$	34,640	$	14,794	$	17,719

Stock Incentive Plan

The Company grants stock option awards, restricted stock and restricted stock units to its employees, directors, and consultants under the Incentive Plan. Under the Incentive Plan, stock option awards are granted with an exercise price equal to the market price of the Company’s stock at the date of grant. Commencing March 1, 2011, stock option awards and restricted stock units granted to employees generally vest 25% each year until fully vested after four years.

In August 2013, December 2014 and December 2019, the Company issued 1,032, 1,250 and 315 performance-based stock options, respectively. These awards vest upon successful completion of specific development milestones. As of December 31, 2021, 100%, 85% and 100% of the August 2013, December 2014 and December 2019 grants, respectively, have vested. During 2020, the Company recognized $1,768 and $684 of stock compensation expense related to milestones within the August 2013 and December 2019 grants for which achievement became probable.

Stock option awards granted to non-employee directors of the Company generally vest over one year. Stock option awards granted to new non-employee directors when they first join the Company’s Board of Directors generally vest, subject to the terms of the Incentive Plan, in 36 equal monthly installments over a three-year period measured from the grant date.

All stock option awards have contractual terms of 10 years. The vesting exercise provisions of all awards granted under the Incentive Plan are subject to acceleration in the event of certain stockholder-approved transactions, or upon the occurrence of a change in control as defined in the Incentive Plan.

Related activity under the Incentive Plan is as follows:

							Weighted
							Average
	*Awards*			*Options*			*Exercise*
	*Available*			*Outstanding*			*Price*
Balance at December 31, 2018		805			17,491		$	6.49
Plan amendment		4,000			−			−
Restricted stock awards granted		(27	)		−			−
Stock option awards granted		(4,511	)		4,511			3.91
Stock option awards exercised		−			(251	)		3.75
Stock option awards cancelled		701			(701	)		6.82
Balance at December 31, 2019		968			21,050		$	5.96
Plan amendment		8,000			−			−
Restricted stock awards granted		(31	)		−			−
Stock option awards granted		(7,469	)		7,469			8.06
Stock option awards exercised		−			(510	)		3.56
Stock option awards cancelled		3,124			(3,124	)		6.93
Balance at December 31, 2020		4,592			24,885		$	6.52
Plan amendment		7,500			−			−
Restricted stock units granted		(1,936	)		−			−
Stock option awards granted		(6,753	)		6,753
Stock option awards exercised		−			(2,705	)		4.36
Stock option awards cancelled		248			(248	)		7.62
Balance at December 31, 2021		3,651			28,685		$	7.90

For stock option awards granted under the Incentive Plan during 2021, 2020, and 2019, the fair value was estimated on the date of grant using a Black-Scholes option pricing model and the assumptions noted in the table below. The weighted average grant date fair value of these awards granted during 2021, 2020, and 2019 was $7.93, $5.48, and $2.63, respectively. The fair value of the stock option awards is amortized to expense over the vesting periods using a straight-line expense attribution method. For restricted stock units granted under the Incentive Plan, the fair value of the awards was determined based on the market value of the Company’s shares on the grant date. The weighted average grant date fair value of these awards was $11.36. The fair value of the restricted stock unit awards is amortized to expense over the vesting periods using a straight-line expense attribution method.

Inducement Equity Incentive Plan

The Company has the ability to grant stock option awards to newly-hired employees as inducements material to each employee entering employment with the Company. Stock option awards granted to newly hired employees generally vest 25% each year until fully vested after four years. Each stock option has a term of 10 years and is subject to the terms and conditions of the Inducement Plan. The vesting and exercise provisions of all awards granted under the Inducement Plan are subject to acceleration in the event of certain stockholder-approved transactions, or upon the occurrence of a change in control as defined in the Inducement Plan.

Related activity under the Inducement Plan is as follows:

							Weighted
							Average
	*Awards*			*Options*			*Exercise*
	*Available*			*Outstanding*			*Price*
Balance at December 31, 2020		229			4,171		$	3.88
Plan amendment		1,500			−			−
Stock option awards granted		(1,003	)		1,003			13.91
Stock option awards exercised		−			(592	)		3.63
Stock option awards cancelled		174			(174	)		3.67
Balance at December 31, 2021		900			4,408		$	6.20

For stock option awards granted under the Inducement Plan during 2021, 2020, and 2019, the fair value was estimated on the date of grant using a Black-Scholes option pricing model and the assumptions noted in the table below. The weighted average grant date fair value of these awards granted during 2021, 2020, and 2019 was $9.65, $2.73, and $2.41, respectively. The fair value of the stock option awards is amortized to expense over the vesting periods using a straight-line expense attribution method.

The following table summarizes the key assumptions used by the Company to value the stock option awards granted under all plans during 2021, 2020, and 2019, respectively. The expected life is based on the average of the assumption that all outstanding stock option awards will be exercised at full vesting and the assumption that all outstanding stock option awards will be exercised at the midpoint of the current date (if already vested) or at full vesting (if not yet vested) and the full contractual term. The expected volatility represents the historical volatility on the Company’s publicly traded common stock. The Company has assumed no expected dividend yield, as dividends have never been paid to stock or option holders and will not be paid for the foreseeable future. The weighted average risk-free interest rate is the implied yield currently available on zero-coupon government issues with a remaining term equal to the expected term.

Weighted Average Assumptions for Stock Option Awards Granted to Employees and Directors under the Plans

	2021			2020			2019
Expected Life		5.5			5.5			5.5
Expected Volatility		84	%		84	%		81	%
Expected Dividend Yield		0.0	%		0.0	%		0.0	%
Risk-Free Interest Rate		1.1	%		0.4	%		1.8	%

The total intrinsic value of stock option awards exercised under the Incentive Plan was $25,484 during 2021, $1,562 during 2020, and $1,127 during 2019. The intrinsic value represents the total proceeds (fair market value at the date of exercise, less the exercise price, times the number of stock option awards exercised) received by all individuals who exercised stock option awards during the period. The total intrinsic value of stock option awards exercised under the Inducement Plan was $6,700 during 2021. No stock option awards were exercised under the Inducement Plan in 2020.

The following table summarizes, at December 31, 2021, by price range: (1) for stock option awards outstanding under the Incentive Plan, the number of stock option awards outstanding, their weighted average remaining life and their weighted average exercise price; and (2) for stock option awards exercisable under the Plan, the number of stock option awards exercisable and their weighted average exercise price:

					Outstanding					Exercisable
						Weighted		Weighted				Weighted
						Average		Average				Average
						Remaining		Exercise				Exercise
Range				Number		Life		Price		Number		Price

$	0	to	3		1,874		5.9	$	2.30		1,158	$	2.12
	3	to	6		10,190		6.5		4.22		7,317		4.41
	6	to	9		10,599		8.2		7.89		4,317		7.56
	9	to	12		8,228		8.1		11.14		2,120		10.86
	12	to	15		1,291		6.8		13.10		535		12.31
	15	to	18		911		9.0		15.95		114		15.56
$	0	to	18		33,093		7.5	$	7.68		15,561	$	6.34

The weighted average remaining contractual life of stock option awards exercisable under the plans at December 31, 2021 was 5.7 years.

The aggregate intrinsic value of stock option awards outstanding and exercisable under the plans at December 31, 2021 was $116,811. The aggregate intrinsic value represents the value (the period’s closing market price, less the exercise price, times the number of in-the-money stock option awards) that would have been received by all stock option award holders under the plans had they exercised their stock option awards at the end of the year.

The total fair value of the stock option awards vested under the plans was $23,395 during 2021, $18,739 during 2020, and $12,499 during 2019.

As of December 31, 2021, the number of stock option awards vested and expected to vest under the plans is 30,268. The weighted average exercise price of these stock option awards is $7.64 and their weighted average remaining contractual life is 7.4 years.

The following table summarizes the changes in the number and weighted-average grant-date fair value of non-vested stock option awards during 2021:

	Non-Vested Stock Option Awards			Weighted Average Grant-Date Fair Value
Balance December 31, 2020		16,020		$	4.25
Stock option awards granted		7,756			3.31
Stock option awards vested		(5,837	)		3.97
Stock option awards forfeited		(407	)		4.14
Balance December 31, 2021		17,532		$	3.86

As of December 31, 2021, there was approximately $107,852 of total unrecognized compensation cost related to non-vested employee stock option awards granted by the Company. That cost is expected to be recognized as follows: $35,060 in 2022, $30,375 in 2023, $27,607 in 2024, and $14,810 in 2025.

Employee Stock Purchase Plan

The Company has reserved a total of 7,975 shares of common stock to be purchased under the ESPP, of which 6,052 shares remain available for purchase at December 31, 2021. Eligible employees may authorize up to 15% of their salary to purchase common stock at the lower of 85% of the beginning or 85% of the ending price during six-month purchase intervals. No more than 3 shares may be purchased by any one employee at the six-month purchase dates and no employee may purchase stock having a fair market value at the commencement date of $25 or more in any one calendar year.

There were 321, 246, and 115 shares of common stock purchased under the ESPP in 2021, 2020, and 2019, respectively, at a weighted average price per share of $6.20, $2.56, and $3.51, respectively. Expense of $1,523, $362, and $232 related to the ESPP was recognized during 2021, 2020, and 2019, respectively. Compensation expense for shares purchased under the ESPP related to the purchase discount and the “look-back” option were determined using a Black-Scholes option pricing model. The weighted average grant date fair values of shares granted under the ESPP during 2021, 2020, and 2019, were $2.80, $1.47, and $2.01, respectively.

Note 13 - Income Taxes - Differences Between the Company's Effective Tax Rate and the Statutory Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income tax benefit at federal statutory rate (21% for 2021, 2020 and 2019)	$ (38,175)	$ (38,391)	$ (22,868)
State and local income taxes net of federal tax benefit	(2,288)	(2,544)	(1,591)
Permanent items	(1,343)	774	691
Rate change		(82)	625
Expiration of attribute carryforwards	(1,057)	3,774	3,976
Research and development tax credits	(5,994)	(4,080)	(4,938)
Foreign rate differential	1,940	542
Other	1,216	1,456	281
Change in valuation allowance	47,954	38,551	23,824
Income tax expense	$ 2,253	$ 0	$ 0

Note 2 - Revenue

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Revenue from Contract with Customer [Text Block]

Note 2 - Revenue

The Company recorded the following revenues for the years ended December 31:

	2021			2020		2019
Product sales, net:
ORLADEYO	$	121,865		$	133	$	−
RAPIVAB		7,231			483		13,864
Peramivir		7,254			2,685		3,669
Total product sales, net		136,350			3,301		17,533
Royalty revenue		(100	)		3,381		6,303
Milestone revenue		15,000			−		−
Collaborative and other research and development revenues:
U.S. Department of Health and Human Services		5,920			9,231		4,898
Torii Pharmaceutical Co., Ltd.		−			1,899		20,101
Total collaborative and other research and development revenues		5,920			11,130		24,999
Total revenues	$	157,170		$	17,812	$	48,835

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

+ Details

Note 3 - Investments (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Debt Securities, Available-for-sale [Table Text Block]

	December 31, 2021
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	4,043	$	17	$	-	$	(7	)	$	4,053
Corporate debt securities		4,294		40		-		(5	)		4,329
Certificates of deposit		1,652		8		-		(1	)		1,659
Total Investments	$	9.989	$	65	$	-	$	(13	)	$	10,041

	December 31, 2020
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	24,986	$	14	$	3	$	(3	)	$	25,000
Certificates of deposit		3,225		11		3		−			3,239
Total Investments	$	28,211	$	25	$	6	$	(3	)	$	28,239

Debt Securities, Held-to-maturity [Table Text Block]

	2021		2020
Maturing in one year or less	$	3,212	$	28,239
Maturing after one year through two years		6,829		−
Total investments	$	10,041	$	28,239

Note 12 - Stock-based Compensation - Stock Plan Activities (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Options outstanding, stock option awards exercised (in shares)	(3,299)
Incentive Plan [Member]
Awards available, beginning balance (in shares)	4,592	968	805
Options outstanding, beginning balance (in shares)	24,885	21,050	17,491
Weighted average exercise price, beginning balance (in dollars per share)			$ 6.49
Awards available, plan amendment (in shares)	7,500	8,000	4,000
Awards available, Restricted stock awards granted (in shares)	(1,936)	(31)	(27)
Awards available, stock option awards granted (in shares)	(6,753)	(7,469)	(4,511)
Options outstanding, stock option awards granted (in shares)	6,753	7,469	4,511
Weighted average exercise price, stock option awards granted (in dollars per share)		$ 8.06	$ 3.91
Options outstanding, stock option awards exercised (in shares)	(2,705)	(510)	(251)
Weighted average exercise price, stock option awards exercised (in dollars per share)	$ 4.36	$ 3.56	$ 3.75
Awards available, stock option awards cancelled (in shares)	248	3,124	701
Options outstanding, stock option awards cancelled (in shares)	(248)	(3,124)	(701)
Weighted average exercise price, stock option awards cancelled (in dollars per share)	$ 7.62	$ 6.93	$ 6.82
Awards available, ending balance (in shares)	3,651	4,592	968
Options outstanding, ending balance (in shares)	28,685	24,885	21,050
Weighted average exercise price, ending balance (in dollars per share)	$ 7.90	$ 6.52	$ 5.96
Inducement Plan [Member]
Awards available, beginning balance (in shares)	229
Options outstanding, beginning balance (in shares)	4,171
Weighted average exercise price, beginning balance (in dollars per share)	$ 3.88
Awards available, plan amendment (in shares)	1,500
Awards available, stock option awards granted (in shares)	(1,003)
Options outstanding, stock option awards granted (in shares)	1,003
Weighted average exercise price, stock option awards granted (in dollars per share)	$ 13.91
Options outstanding, stock option awards exercised (in shares)	(592)
Weighted average exercise price, stock option awards exercised (in dollars per share)	$ 3.63
Awards available, stock option awards cancelled (in shares)	174
Options outstanding, stock option awards cancelled (in shares)	(174)
Weighted average exercise price, stock option awards cancelled (in dollars per share)	$ 3.67
Awards available, ending balance (in shares)	900	229
Options outstanding, ending balance (in shares)	4,408	4,171
Weighted average exercise price, ending balance (in dollars per share)	$ 6.20	$ 3.88

Note 10 - Lease Obligations (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Lessee, Operating Lease, Assets and Liabilities [Table Text Block]

	Balance Sheet Location	2021		2020
Assets:
Operating lease assets, net	Other Assets	$	6,472	$	3,802
Liabilities:
Current operating lease liabilities	Lease financing obligation – current liabilities	$	1,819	$	1,179
Non-current operating lease liabilities	Lease financing obligation – long-term liabilities		5,962		3,871
Total operating lease liabilities		$	7,781	$	5,050

Lessee, Operating Lease, Liability, Maturity [Table Text Block]

2022	$	2,099
2023		1,870
2024		1,321
2025		1,060
2026		593
Thereafter		6,734
Total lease payments		13,677
Less imputed interest		(5,896	)
Total	$	7,781

Note 10 - Lease Obligations - Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
2022	$ 2,099
2023	1,870
2024	1,321
2025	1,060
2026	593
Thereafter	6,734
Total lease payments	13,677
Less imputed interest	(5,896)
Total	7,781	$ 5,050
Accrued Liabilities, Current and Other Noncurrent Liabilities [Member]
Total	$ 7,781

Note 7 - Accrued Expenses

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Accounts Payable and Accrued Liabilities Disclosure [Text Block]

Note 7 – Accrued Expenses

Accrued expenses consisted of the following:

	December 31,
	2021		2020
Compensation and benefits	$	20,674	$	11,030
Development costs		30,215		15,150
Revenue-related reserves for discounts and allowances		5,957		2
Royalties payable		4,426		−
Inventory		3,793		2,453
Professional fees		1,305		333
Duties and taxes		2,622		80
Other		3,678		4,894
Total accrued expenses	$	72,670	$	33,942

Note 10 - Lease Obligations

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Lessee, Operating Leases [Text Block]

Note 10 — Lease Obligations

The Company leases certain assets under operating leases, which primarily consisted of real estate leases, laboratory equipment leases and office equipment leases as of December 31, 2021. Renewal options for our leases range from 1 to 5 years in length and begin from 2023 through 2026. The weighted average lease term for the Company’s operating leases was 9.2 years. The weighted average discount rate for the Company’s operating leases was 11.2%.

Aggregate lease expense under operating leases was $1,795 and $1,754 for the years ended December 31, 2021 and 2020, respectively.

All of the Company’s leases qualify as operating leases. The following table summarizes the presentation in the consolidated balance sheets of the Company’s operating leases:

	Balance Sheet Location	2021		2020
Assets:
Operating lease assets, net	Other Assets	$	6,472	$	3,802
Liabilities:
Current operating lease liabilities	Lease financing obligation – current liabilities	$	1,819	$	1,179
Non-current operating lease liabilities	Lease financing obligation – long-term liabilities		5,962		3,871
Total operating lease liabilities		$	7,781	$	5,050

Operating lease assets are recorded net of accumulated amortization of $2,626 and $2,641 as of December 31, 2021 and 2020, respectively. Cash paid for amounts included in the measurement of lease liabilities was $1,615 and $1,696 for the years ended December 31, 2021 and 2020, respectively.

Maturities of operating lease liabilities as of December 31, 2021, are as follows (in thousands):

2022	$	2,099
2023		1,870
2024		1,321
2025		1,060
2026		593
Thereafter		6,734
Total lease payments		13,677
Less imputed interest		(5,896	)
Total	$	7,781

Note 6 - Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Property, Plant and Equipment [Table Text Block]

	December 31,
	2021			2020
Furniture and fixtures	$	1,122		$	722
Office equipment		467			211
Software		1,159			1,159
Laboratory equipment		4,247			3,774
Leasehold improvements		9,832			8,583
Total property and equipment	$	16,827		$	14,449
Less accumulated depreciation and amortization		(8,113	)		(7,336	)
Property and equipment, net	$	8,714		$	7,113

Note 5 - Inventory

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Inventory Disclosure [Text Block]

Note 5 – Inventory

At December 31, 2021 and 2020, the Company’s inventory primarily related to ORLADEYO. Additionally, inventory included RAPIVAB and peramivir, which is manufactured for the Company’s partners.

The Company’s inventories consisted of the following:

	December 31,
	2021			2020
Raw materials	$	5,658		$	206
Work-in-process		9,669			2,555
Finished goods		709			4,548
Total inventory	$	16,036		$	7,309
Reserves		(245	)		(270	)
Total inventory, net	$	15,791		$	7,039

Note 6 - Property and Equipment

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Property, Plant and Equipment Disclosure [Text Block]

Note 6 — Property and Equipment

Property and equipment consisted of the following at December 31:

	December 31,
	2021			2020
Furniture and fixtures	$	1,122		$	722
Office equipment		467			211
Software		1,159			1,159
Laboratory equipment		4,247			3,774
Leasehold improvements		9,832			8,583
Total property and equipment	$	16,827		$	14,449
Less accumulated depreciation and amortization		(8,113	)		(7,336	)
Property and equipment, net	$	8,714		$	7,113

Depreciation and amortization expense for the years ended December 31, 2021, 2020, and 2019 was $777, $748, and $724, respectively.

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
ASSETS
Cash and cash equivalents	$ 504,389	$ 272,127
Restricted cash	3,345	2,221
Investments	3,212	28,239
Trade receivables	29,413	8,646
Inventory	15,791	7,039
Prepaid expenses and other current assets	9,986	5,528
Total current assets	566,136	323,800
Property and equipment, net	8,714	7,113
Long-term investments	6,829
Other assets	6,472	3,802
Total assets	588,151	334,715
LIABILITIES AND STOCKHOLDERS’ DEFICIT
Accounts payable	27,808	18,713
Accrued expenses	72,670	33,942
Interest payable		21,670
Deferred revenue	1,421	150
Lease financing obligation	1,819	1,179
Non-recourse notes payable		30,000
Total current liabilities	103,718	105,654
Royalty financing obligations	449,375	124,717
Non-current operating lease liabilities	5,962	3,871
Secured term loan	136,082	119,735
Stockholders’ deficit:
Preferred stock, $0.01 par value; shares authorized — 5,000; no shares outstanding	0	0
Common stock, $0.01 par value; shares authorized — 450,000 Issued and outstanding – 184,350 and 176,883 at December 31, 2021 and 2020, respectively	1,843	1,769
Additional paid-in capital	1,098,498	1,002,408
Accumulated other comprehensive income	177	3
Accumulated deficit	(1,207,504)	(1,023,442)
Total stockholders’ deficit	(106,986)	(19,262)
Total liabilities and stockholders’ deficit	$ 588,151	$ 334,715

Note 12 - Stock-Based Compensation - Stock-based Compensation Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expense	$ 34,640	$ 14,794	$ 17,719
Research and Development Expense [Member]
Share-based Payment Arrangement, Expense	20,179	10,222	13,977
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense	$ 14,461	$ 4,572	$ 3,742

Note 12 - Stock-based Compensation - Weighted Average Assumptions for Stock Option Awards Granted to Employees and Directors Under the Plans (Details) - Incentive Plan and Inducement Plan [Member]	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Expected Life (Year)	5 years 6 months	5 years 6 months	5 years 6 months
Expected Volatility	84.00%	84.00%	81.00%
Expected Dividend Yield	0.00%	0.00%	0.00%
Risk-Free Interest Rate	1.10%	0.40%	1.80%

Note 13 - Income Taxes - Differences Between the Company's Effective Tax Rate and the Statutory Tax Rate (Details) (Parentheticals)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income tax benefit at federal statutory rate, percentage	21.00%	21.00%	21.00%

Note 15- Collaborative and Other Relationships (Details Textual) $ in Thousands								1 Months Ended		12 Months Ended			70 Months Ended
	Sep. 15, 2021 USD ($)	Sep. 01, 2021 USD ($)	Mar. 04, 2020 USD ($)	Nov. 05, 2019 USD ($)	Sep. 06, 2018 USD ($)	Jun. 16, 2015 USD ($)	Sep. 30, 2013 USD ($)	Aug. 31, 2020 USD ($)	Jun. 30, 2000 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2015 USD ($)
Revenue from Contract with Customer, Including Assessed Tax										$ 157,170	$ 17,812	$ 48,835
Arbitration Proceedings of SUL Agreement [Member]
Litigation Settlement, Amount Awarded from Other Party			$ 5,000
Arbitration Proceedings of SUL Agreement [Member] \| Other Income [Member]
Gain (Loss) Related to Litigation Settlement, Total											8,893
Arbitration Proceedings of SUL Agreement [Member] \| Selling, General and Administrative Expenses [Member]
Legal Fees											5,026
US Department of Health and Human Services [Member]
Collaborative Agreement Contract Value					$ 34,660
Contract Term (Year)					5 years
US Department of Health and Human Services [Member] \| RAPIVAB [Member]
Maximum Number of Products, Doses					50,000
Number of Product Delivered, Doses										9,980		20,000
Proceeds from Collaborators										$ 6,918		$ 13,900
Number of Additional Products, Doses		10,000
Revenue from Contract with Customer, Including Assessed Tax		$ 6,900
Torii Pharmaceutical Co. [Member]
Revenue from Contract with Customer, Including Assessed Tax				$ 22,000
Potential Milestone Payments Receivable if Regulatory Approval Before December 31, 2021				$ 15,000
Maximum Customary Reduction on Royalty Rate				50.00%
Royalty Payments Receivable, Expiration Term From First Commercial (Year)				10 years
Contract with Customer, Liability, Revenue Recognized											$ 1,899	$ 20,101
Torii Pharmaceutical Co. [Member] \| Minimum [Member]
Royalty Rate if Maintains Sakigake Designation				20.00%
Torii Pharmaceutical Co. [Member] \| Maximum [Member]
Royalty Rate if Maintains Sakigake Designation				40.00%
CSL Limited [Member
Proceeds from License Fees Received						$ 33,740
Milestone Payment Received													$ 12,000
Base Contract [Member]
Government Contract Receivable														$ 16,265
Additional Development Options [Member]
Government Contract Receivable														22,855
ASPRBARDA Contract [Member]
Government Contract Receivable														$ 39,120
Proceeds from awards for Research and Development Contracts										$ 20,574
AECOM and IRL [Member]
Milestone Payment Minimum									$ 1,400
Milestone Payment Maximum									4,000
Annual License Fee Minimum									150
Annual License Fee Maximum									$ 500
National Institute of Allergy and Infectious Diseases [Member]
Expected Receivable From Awards for Research and Development Contracts	$ 47,315						$ 45,931
Collaborative Agreement Contract, Covenant, Maximum Amount of Funding								$ 43,908
Collaborative Agreement Contract Value								$ 6,326
UAB [Member]
Period of Agreement (Year)										25 years
Renewable Period of Agreement (Year)										5 years

Consolidated Balance Sheets (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 2021	Dec. 31, 2020
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000	5,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	450,000	450,000
Common stock, shares issued (in shares)	184,350	176,883
Common stock, shares outstanding (in shares)	184,350	176,883

Consolidated Statements of Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues:
Revenues	$ 157,170	$ 17,812	$ 48,835
Expenses
Cost of products sold	7,229	1,550	3,726
Research and development	208,808	122,964	107,068
Selling, general and administrative	118,818	67,929	37,121
Royalty	35	126	375
Total operating expenses	334,890	192,569	148,290
Loss from operations	(177,720)	(174,757)	(99,455)
Interest and other income	62	9,420	1,933
Interest expense	(59,294)	(14,501)	(11,892)
Gain (loss) on extinguishment of debt	55,838	(2,011)
Foreign currency (losses) gains, net	(695)	(965)	517
Loss before income taxes	(181,809)	(182,814)	(108,897)
Income tax expense	2,253	0	0
Net loss	(184,062)	(182,814)	(108,897)
Foreign currency translation adjustment	189
Unrealized (loss) gain on available for sale investments	(15)	(36)	336
Net comprehensive loss	$ (183,888)	$ (182,850)	$ (108,561)
Basic and diluted net loss per common share (in dollars per share)	$ (1,030.00)	$ (1,090.00)	$ (940)
Weighted average shares outstanding (in shares)	179,117	167,267	115,600
Product [Member]
Revenues:
Revenues	$ 136,350	$ 3,301	$ 17,533
Royalty [Member]
Revenues:
Revenues	(100)	3,381	6,303
Milestone [Member]
Revenues:
Revenues	15,000
Collaborative and Other Research and Development [Member]
Revenues:
Revenues	$ 5,920	$ 11,130	$ 24,999

Note 11 - Stockholders' Equity

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Stockholders' Equity Note Disclosure [Text Block]

Note 11 — Stockholders’ Equity

Sales of Common Stock

On November 18, 2019, the Company completed an underwritten public offering of 43,621 shares of its common stock, offered at a price to the public of $1.45 per share, including shares issued pursuant to the underwriters’ 30-day option to purchase additional shares, which was exercised in full. The net proceeds from this offering were approximately $58,500 after deducting underwriting discounts and commissions and estimated offering expenses.

On November 21, 2019, the Company completed an offering of pre-funded warrants to purchase up to 11,765 shares of its common stock at a price of $1.69 per warrant. Each pre-funded warrant is exercisable subject to conditions in the warrant agreement into 1 share of common stock at an exercise price of $0.01 per share. The net proceeds from this offering were $19,882, excluding any proceeds the Company may receive upon the subsequent exercise of the pre-funded warrants. All warrants issued in this offering remain outstanding at December 31, 2021.

On April 24, 2020, the Company filed a $500,000 shelf registration statement on Form S-3 with the SEC. This shelf registration statement became effective on May 14, 2020 and allows the Company to sell securities, including common stock, preferred stock, depositary shares, purchase contracts, warrants, debt securities, and units, from time to time at prices and on terms to be determined at the time of sale.

On June 1, 2020, the Company issued 22,044 shares of common stock to the public at a purchase price of $4.50 per share and pre-funded warrants to purchase 3,511 shares of common stock at a purchase of $4.49 per pre-funded warrant, for total net proceeds to the Company of $108,096 million after deducting underwriting discounts and commissions and other offering expenses. Each pre-funded warrant is exercisable subject to conditions in the warrant agreement into 1 share of common stock at an exercise price of $0.01 per share. All warrants issued in this offering remain outstanding at December 31, 2021.

On March 1, 2021, the Company filed an automatic shelf registration statement on Form S-3 with the SEC. This shelf registration statement became effective automatically upon filing and allows the Company to sell an indeterminate number of securities, including common stock, preferred stock, depositary shares, purchase contracts, warrants, debt securities, and units, from time to time at prices and on terms to be determined at the time of sale.

On November 19, 2021, concurrent with the Company entering into the 2021 RPI Royalty Purchase Agreement, the Company and RPI entered into a Common Stock Purchase Agreement, pursuant to which the Company issued 3,846,154 shares of the Company’s common stock to RPI for an aggregate purchase price of $50,000, at a price of $13.00 per share, calculated based on the 20-day volume weighted average price. The $13.00 per share price represents a premium of $1.11 over the closing price of $11.89 of the Company’s common stock on November 17, 2021, the last trading day prior to the execution of the Common Stock Purchase Agreement. The premium of $4,269 paid by RPI on the purchase of the Company’s common stock has been deferred and is being amortized as a component of interest expense of the 2021 RPI royalty financing obligation.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

Note 6 - Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property and equipment	$ 16,827	$ 14,449
Less accumulated depreciation and amortization	(8,113)	(7,336)
Property and equipment, net	8,714	7,113
Furniture and Fixtures [Member]
Property and equipment	1,122	722
Office Equipment [Member]
Property and equipment	467	211
Software Development [Member]
Property and equipment	1,159	1,159
Laboratory Equipment [Member]
Property and equipment	4,247	3,774
Leasehold Improvements [Member]
Property and equipment	$ 9,832	$ 8,583

Note 13 - Income Taxes

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Income Tax Disclosure [Text Block]

Note 13 — Income Taxes

The Company has incurred net losses since inception and, consequently, has not recorded any U.S. Federal and state income tax expense or benefit.

The components of loss before provision for income taxes were as follows:

	Years Ended December 31,
	2021			2020
Domestic	$	(159,632	)	$	(176,613	)
Foreign		(22,177	)		(6,201	)
Loss before provision for income taxes	$	(181,809	)	$	(182,814	)

The differences between the Company’s effective tax rate and the statutory tax rate in 2021, 2020, and 2019, are as follows:

	2021			2020			2019
Income tax benefit at federal statutory rate (21% for 2021, 2020 and 2019)	$	(38,175	)	$	(38,391	)	$	(22,868	)
State and local income taxes net of federal tax benefit		(2,288	)		(2,544	)		(1,591	)
Permanent items		(1,343	)		774			691
Rate change		−			(82	)		625
Expiration of attribute carryforwards		(1,057	)		3,774			3,976
Research and development tax credits		(5,994	)		(4,080	)		(4,938	)
Foreign rate differential		1,940			542			-
Other		1,216			1,456			281
Change in valuation allowance		47,954			38,551			23,824
Income tax expense	$	2,253		$	−		$	−

The Company recognizes the impact of a tax position in its financial statements if it is more likely than not that the position will be sustained on audit based on the technical merits of the position. The Company has concluded that it has an uncertain tax position pertaining to its research and development and orphan drug credit carryforwards. The Company has established these credits based on information and calculations it believes are appropriate and the best estimate of the underlying credit. Any changes to the Company’s unrecognized tax benefits are offset by an adjustment to the valuation allowance and there would be no impact on the Company’s financial statements. The Company does not expect its unrecognized tax benefits to change significantly over the next 12 months.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:

	2021		2020
Balance at January 1,	$	8,230	$	7,210
Additions to current period tax positions		1,499		1,020
Balance at December 31,	$	9,729	$	8,230

The Company’s ability to utilize the net operating loss and tax credit carryforwards in the future may be subject to substantial restrictions in the event of past or future ownership changes as defined in Section 382 of the Internal Revenue Code of 1986, as amended and similar state tax law.

Significant components of the Company’s deferred tax assets and liabilities are as follows:

	2021			2020
Deferred tax assets:
Net federal and state operating losses	$	113,649		$	159,939
Research and development credits		71,197			66,331
Royalty income		106,007			28,034
Stock-based compensation		14,512			10,732
Capitalized R&D		8,997			−
Leasing obligations		1,836			1,135
Other		4,809			5,563
Total deferred tax assets		321,007			271,734
Deferred tax liabilities:
Fixed assets		(607	)		(124	)
Right of use asset		(1,527	)		(854	)
Total deferred tax liabilities		(2,134	)		(978	)
Valuation allowance		(318,714	)		(270,756	)
Net deferred tax assets	$	159		$	−

The majority of the Company’s deferred tax assets relate to net operating loss and research and development carryforwards that can only be realized if the Company is profitable in future periods. It is uncertain whether the Company will realize any tax benefit related to these carryforwards. Accordingly, the Company has provided a valuation allowance against substantially all the net deferred tax assets due to uncertainties as to their ultimate realization. The valuation allowance will remain at the full amount of the deferred tax assets until it is more likely than not that the related tax benefits will be realized. The Company’s valuation allowance increased by $47,954, $38,551, and $23,824 in 2021, 2020, and 2019, respectively.

As of December 31, 2021, the Company had U.S. federal operating loss carryforwards of $480,331, state operating loss carryforwards of $177,567, foreign net operating losses of $29,355, and U.S. research and development and orphan drug credit carryforwards of $80,925, which will expire at various dates from 2022 through 2041. Federal losses, state losses, research and development credit carryforwards began expiring in 2020. The foreign net operating losses have an indefinite carryforward period.

Tax years 2018-2021 remain open to examination by the major taxing jurisdictions to which the Company is subject. Additionally, years prior to 2017 are also open to examination to the extent of loss and credit carryforwards from those years. The Company recognizes interest and penalties accrued related to unrecognized tax benefits as components of its income tax provision. However, there were no provisions or accruals for interest and penalties in 2021, 2020 and 2019.

As of December 31, 2021, the Company has accumulated undistributed earnings of $750, generated by our foreign subsidiaries which have already been subject to local and U.S. tax (as part of the GILTI provisions). We intend to indefinitely reinvest these earnings, as well as future earnings from our foreign subsidiaries to fund out international operations. In addition, we expect future U.S. cash generation will be sufficient to meet future U.S cash needs.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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+ Details

Note 13 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	Years Ended December 31,
	2021			2020
Domestic	$	(159,632	)	$	(176,613	)
Foreign		(22,177	)		(6,201	)
Loss before provision for income taxes	$	(181,809	)	$	(182,814	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2021			2020			2019
Income tax benefit at federal statutory rate (21% for 2021, 2020 and 2019)	$	(38,175	)	$	(38,391	)	$	(22,868	)
State and local income taxes net of federal tax benefit		(2,288	)		(2,544	)		(1,591	)
Permanent items		(1,343	)		774			691
Rate change		−			(82	)		625
Expiration of attribute carryforwards		(1,057	)		3,774			3,976
Research and development tax credits		(5,994	)		(4,080	)		(4,938	)
Foreign rate differential		1,940			542			-
Other		1,216			1,456			281
Change in valuation allowance		47,954			38,551			23,824
Income tax expense	$	2,253		$	−		$	−

Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]

	2021		2020
Balance at January 1,	$	8,230	$	7,210
Additions to current period tax positions		1,499		1,020
Balance at December 31,	$	9,729	$	8,230

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	2021			2020
Deferred tax assets:
Net federal and state operating losses	$	113,649		$	159,939
Research and development credits		71,197			66,331
Royalty income		106,007			28,034
Stock-based compensation		14,512			10,732
Capitalized R&D		8,997			−
Leasing obligations		1,836			1,135
Other		4,809			5,563
Total deferred tax assets		321,007			271,734
Deferred tax liabilities:
Fixed assets		(607	)		(124	)
Right of use asset		(1,527	)		(854	)
Total deferred tax liabilities		(2,134	)		(978	)
Valuation allowance		(318,714	)		(270,756	)
Net deferred tax assets	$	159		$	−

Note 4 - Trade Receivables - Summary of Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Receivables	$ 1,980	$ 8,243
Billed Revenues [Member]
Receivables	310	2,816
Unbilled Revenues [Member]
Receivables	1,670	5,427
US Department of Health and Human Services [Member]
Receivables	1,675	5,402
US Department of Health and Human Services [Member] \| Billed Revenues [Member]
Receivables	5
US Department of Health and Human Services [Member] \| Unbilled Revenues [Member]
Receivables	1,670	5,402
Royalty Receivables from Partners [Member]
Receivables	305	2,841
Royalty Receivables from Partners [Member] \| Billed Revenues [Member]
Receivables	$ 305	2,816
Royalty Receivables from Partners [Member] \| Unbilled Revenues [Member]
Receivables		$ 25

Note 7 - Accrued Expenses - Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Compensation and benefits	$ 20,674	$ 11,030
Development costs	30,215	15,150
Royalties payable	4,426
Inventory	3,793	2,453
Professional fees	1,305	333
Duties and taxes	2,622	80
Other	3,678	4,894
Total accrued expenses	$ 72,670	$ 33,942

Note 10 - Lease Obligations -Balance Sheets of the Company's Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Liabilities:
Current operating lease liabilities	$ 1,819	$ 1,179
Non-current operating lease liabilities	5,962	3,871
Total operating lease liabilities	7,781	5,050
Other Assets [Member]
Assets:
Operating lease assets, net	$ 6,472	$ 3,802

Note 14 - Employee 401(k) Plan

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Retirement Benefits [Text Block]

Note 14 — Employee 401(k) Plan

In January 1991, the Company adopted an employee retirement plan (“401(k) Plan”) under Section 401(k) of the Internal Revenue Code covering all employees. Employee contributions may be made to the 401(k) Plan up to limits established by the Internal Revenue Service. Company matching contributions may be made at the discretion of the Board of Directors. The Company made matching contributions of $2,834, $1,569, and $926 in 2021, 2020, and 2019, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Note 12 - Stock-based Compensation - Changes in the Number and Weighted-Average Grant-Date Fair Value (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Non-vested stock option awards (in shares) \| shares	16,020
Weighted average grant-date fair value (in dollars per share) \| $ / shares	$ 4.25
Stock option awards granted (in shares) \| shares	7,756
Stock option awards granted (in dollars per share) \| $ / shares	$ 3.31
Stock option awards vested (in shares) \| shares	(5,837)
Stock option awards vested (in dollars per share) \| $ / shares	$ 3.97
Stock option awards forfeited (in shares) \| shares	(407)
Stock option awards forfeited (in dollars per share) \| $ / shares	$ 4.14
Non-vested stock option awards (in shares) \| shares	17,532
Weighted average grant-date fair value (in dollars per share) \| $ / shares	$ 3.86

Note 15- Collaborative and Other Relationships

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Collaborative Arrangement Disclosure [Text Block]

Note 15 — Collaborative and Other Relationships

National Institute of Allergy and Infectious Diseases (“NIAID/HHS”). In September 2013, NIAID/HHS contracted with the Company for the development of galidesivir as a treatment for Marburg virus disease and subsequently, Yellow Fever and Ebola virus disease. On September 15, 2021, the Company entered into an amendment to pay for certain additional costs, including additional manufacturing development costs and overhead, and to change the total value of the contract, as amended, to $47,315 from $45,931. This is the commencement of closing out the contract. All options under the contract have been awarded.

In August 2020, NIAID/HHS awarded the Company a new contract, with potential aggregate funding up of to $43,908 if all contract options are exercised, to manufacture and evaluate the safety, efficacy and tolerability of galidesivir. NIAID/HHS made an initial award of $6,326 to the Company under this contract.

Biomedical Advanced Research and Development Authority (“BARDA/HHS”). In March 2015, BARDA/HHS awarded the Company a contract for the continued development of galidesivir as a potential treatment for diseases caused by RNA pathogens, including filoviruses. This BARDA/HHS contract includes a base contract of $16,265 to support galidesivir drug manufacturing, as well as $22,855 in additional development options that can be exercised by the government, bringing the potential value of the contract to $39,120. As of December 31, 2021, a total of $20,574 has been awarded under exercised options within this contract. The most recent development option was completed as of December 31, 2021.

The contracts with NIAID/HHS and BARDA/HHS are cost-plus-fixed-fee contracts. That is, the Company is entitled to receive reimbursement for all costs incurred in accordance with the contract provisions that are related to the development of galidesivir plus a fixed fee, or profit. BARDA/HHS and NIAID/HHS will make periodic assessments of progress, and the continuation of the contracts is based on the Company’s performance, the timeliness and quality of deliverables, and other factors. The government has rights under certain contract clauses to terminate these contracts. These contracts are terminable by the government at any time for breach or without cause.

U.S. Department of Health and Human Services (“HHS”). In September 2018, HHS awarded the Company a $34,660 contract for the procurement of up to 50,000 doses of RAPIVAB (peramivir injection) over a five-year period. The Company delivered 20,000 doses of RAPIVAB under this contract in 2019 for a total price of approximately $13.9 million. For the year ended December 31, 2021, the Company delivered a total of 9,980 doses for $6,918. On September 1, 2021, the Company announced that HHS exercised its option to purchase an additional 10,000 doses of RAPIVAB under this contract for a total price of approximately $6.9 million which has not been delivered as of December 31, 2021. As of December 31, 2021, the Company has delivered a total of 29,980 RAPIVAB doses of the 50,000 RAPIVAB doses available under the contract with HHS.

Torii Pharmaceutical Co., Ltd. (“Torii”). On November 5, 2019, the Company entered into a Commercialization and License Agreement with Torii (the “Torii Agreement”), granting Torii the exclusive right to commercialize ORLADEYO for the prevention of hereditary angioedema (“HAE”) attacks in Japan.

Under the Torii Agreement, the Company received an upfront, non-refundable payment of $22,000. The Japanese National Health Insurance System’s (“NHI”) approval of the addition of ORLADEYO to the NHI drug price list in April 2021 triggered a $15,000 milestone payment from Torii to the Company, which was received in May 2021.

In addition, under the Torii Agreement, the Company is entitled to receive tiered royalty payments, ranging from 20% to 40% of annual net sales of ORLADEYO in Japan during each calendar year. Torii’s royalty payment obligations are subject to customary reductions in certain circumstances, but may not be reduced by more than 50% of the amount that otherwise would have been payable to the Company in the applicable calendar quarter. Torii’s royalty payment obligations commenced upon the first commercial sale of ORLADEYO in Japan and expire upon the later of (i) the tenth anniversary of the date of first commercial sale of ORLADEYO in Japan, (ii) the expiration of the Company’s patents covering ORLADEYO, and (iii) the expiration of regulatory exclusivity for ORLADEYO in Japan. The Company is responsible for supplying Torii with its required amounts of ORLADEYO. The activities of the parties pursuant to the Torii Agreement are overseen by a joint steering committee, composed of an equal number of representatives from each party to coordinate the development and commercialization of ORLADEYO in Japan. Torii launched ORLADEYO in Japan on April 23, 2021.

The Company identified performance obligations related to (i) the license to develop and commercialize ORLADEYO, (ii) regulatory approval support and (iii) reimbursement pricing approval support. These were each determined to be distinct from the other performance obligations. The Company allocated the $22,000 upfront consideration to the identified performance obligations using estimation approaches to determine the standalone selling prices under ASC Topic 606. Specifically, in determining the value related to the license, a valuation approach utilizing risk adjusted discounted cash flow projections was used, and an expected cost plus margin approach was utilized for the other performance obligations. For the year ended December 31, 2020, $1,899 of the $22,000 upfront payment was recognized as revenue as the services were delivered. Prior to 2020, the Company had recognized as revenue $20,101 of the $22,000 upfront payment.

Seqirus UK Limited (“SUL”). On June 16, 2015, the Company and SUL, a limited company organized under the laws of the United Kingdom and a subsidiary of CSL Limited, a company organized under the laws of Australia, entered into a License Agreement (the “SUL Agreement”) granting SUL and its affiliates worldwide rights to develop, manufacture and commercialize RAPIVAB (peramivir injection) for the treatment of influenza except for the rights to conduct such activities in Israel, Japan, Korea and Taiwan (the permitted geographies together constituting the “Territory”). Under the terms of the SUL Agreement, the Company received an upfront payment of $33,740 and has achieved all development milestones under the contract totaling $12,000.

On March 4, 2020, the International Court of Arbitration of the International Chamber of Commerce (“ICC Tribunal”) delivered a Partial Arbitration Award (the “Partial Arbitration Award”) in an arbitration matter between the Company and SUL with respect to the SUL Agreement. In the Partial Arbitration Award, the ICC Tribunal found that, during the term, SUL materially breached and abandoned its core duties to the Company under the Diligent Efforts (as defined in the SUL Agreement) requirements of the SUL Agreement as applicable in the U.S. The ICC Tribunal granted a declaratory judgment in favor of the Company terminating the SUL Agreement and restoring all rights to peramivir to the Company. The parties agreed on a transition process for the product, with a full transition of commercialization of the product in the U.S. and Australia returned to the Company as of August 1, 2020 and November 1, 2020, respectively. The ICC Tribunal also awarded the Company its attorneys’ fees and expenses incurred in securing the declaratory judgment as well as the costs incurred by the Company in the arbitration. Finally, the ICC Tribunal found that SUL breached the SUL Agreement by failing to pay the milestone payment due to the Company within 30 days of the approval of peramivir for adult use in the European Union and awarded the Company $5,000 (plus interest) for this claim. The ICC Tribunal retained jurisdiction for further proceedings relating to the award of attorneys’ fees and for any dispute relating to the return to the Company of all rights to peramivir in the Territory. The Company recognized a settlement gain of $8,893 in other income and legal fees and other expenses of $5,026 in selling, general and administrative expenses for the year ended December 31, 2020.

Shionogi & Co., Ltd. (“Shionogi”). In February 2007, the Company entered into an exclusive license agreement with Shionogi to develop and commercialize peramivir in Japan for the treatment of seasonal and potentially life-threatening human influenza. Under the terms of the agreement, Shionogi obtained rights to injectable formulations of peramivir in Japan. The Company developed peramivir under a license from UAB and will owe sublicense payments to UAB on any future milestone payments and/or royalties received by the Company from Shionogi. In October 2008, the Company and Shionogi amended the license agreement to expand the territory covered by the agreement to include Taiwan. Shionogi has commercially launched peramivir under the commercial name RAPIACTA in Japan and Taiwan.

Green Cross Corporation (“Green Cross”). In June 2006, the Company entered into an agreement with Green Cross to develop and commercialize peramivir in Korea. Under the terms of the agreement, Green Cross is responsible for all development, regulatory, and commercialization costs in Korea and the Company is entitled to share in profits resulting from the sale of peramivir in Korea, including the sale of peramivir to the Korean government for stockpiling purposes. Furthermore, Green Cross will pay the Company a premium over its cost to supply peramivir for development and any future marketing of peramivir products in Korea.

Albert Einstein College of Medicine of Yeshiva University and Industrial Research, Ltd. (“AECOM” and “IRL,” respectively). In June 2000, the Company licensed a series of potent inhibitors of PNP from AECOM and IRL, (together, the “Licensors”). The lead product candidate from this collaboration is forodesine. The Company has obtained worldwide exclusive rights to develop and ultimately distribute this, or any other, product candidates that might arise from research on these inhibitors. The Company has the option to expand the agreement to include other inventions in the field made by the investigators or employees of the Licensors. Under this agreement, as amended and restated, the Company has agreed to use commercially reasonable efforts to develop these drugs and to pay certain milestone payments for each licensed product (which range in the aggregate from $1,400 to almost $4,000 per indication) for future development, single digit royalties on net sales of any resulting product made by the Company, and to share a portion of future payments received from other third-party partners, if any. In addition, the Company has agreed to pay annual license fees, which can range from $150 to $500, that are creditable against actual royalties and other payments due to the Licensors. The Licensors have also granted the Company an exclusive worldwide license of galidesivir for any antiviral use.

The University of Alabama at Birmingham (“UAB”). The Company currently has agreements with UAB for influenza neuraminidase and complement inhibitors. Under the terms of these agreements, UAB performed specific research for the Company in return for research payments and license fees. UAB has granted the Company certain rights to any discoveries in these areas resulting from research developed by UAB or jointly developed by UAB with the Company. The Company has agreed to pay single digit royalties on sales of any resulting product and to share in future payments received from other third-party partners. The Company has completed the research under the UAB agreements. These two agreements each have an initial 25-year term, are automatically renewable for five-year terms throughout the life of the last patent and are terminable by the Company upon three months’ notice and by UAB under certain circumstances. Upon termination, both parties shall cease using the other parties’ proprietary and confidential information and materials, the parties shall jointly own joint inventions and UAB shall resume full ownership of all UAB licensed products. There is currently no activity between the Company and UAB on these agreements, but when the Company licenses this technology, such as in the case of the Shionogi and Green Cross collaborations, or commercializes products related to these programs, the Company will owe sublicense fees or royalties on amounts received.

Note 8 - Royalty Monetizations - Schedule of Royalty Financing Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Royalty financing obligation, net of issuance costs	$ 298,142	$ 122,609
Non-cash Interest expense on Royalty financing obligation	37,670	2,108
Balance	124,717
Royalty revenues paid and payable	(11,154)
Balance	449,375	124,717
2020 RPI Royalty Agreement [Member]
Royalty financing obligation, net of issuance costs		122,609
Non-cash Interest expense on Royalty financing obligation	33,308	2,108
Balance	124,717
Royalty revenues paid and payable	(10,801)
Balance	$ 147,224	$ 124,717
Effective interest rate	27.30%
2021 RPI Royalty Agreement [Member]
Royalty financing obligation, net of issuance costs	$ 150,833
Non-cash Interest expense on Royalty financing obligation	2,897
Royalty revenues paid and payable	(353)
Balance	$ 153,377
Effective interest rate	16.50%
OMERS Royalty Agreement [Member]
Royalty financing obligation, net of issuance costs	$ 147,309
Non-cash Interest expense on Royalty financing obligation	1,465
Balance	$ 148,774
Effective interest rate	8.50%

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Note 8 - Royalty Monetizations

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Royalty Monetization [Text Block]

Note 8 — Royalty Monetizations

RAPIACTA

Overview

On March 9, 2011, the Company completed a $30,000 financing transaction to monetize certain future royalty and milestone payments under the Company’s agreement with Shionogi (the “Shionogi Agreement”), pursuant to which Shionogi licensed from the Company the rights to market RAPIACTA in Japan and Taiwan. The Company received net proceeds of $22,691 from the transaction after transaction costs of $4,309 and the establishment of a $3,000 interest reserve account by Royalty Sub, available to help cover interest shortfalls in the future. All of the interest reserve account has been fully utilized with the September 2012 interest payment.

As part of the transaction, the Company entered into a purchase and sale agreement dated as of March 9, 2011 with JPR Royalty Sub, LLC, a wholly-owned subsidiary of the Company (“Royalty Sub”), whereby the Company transferred to Royalty Sub, among other things, (i) its rights to receive certain royalty and milestone payments from Shionogi arising under the Shionogi Agreement, and (ii) the right to receive payments under a Japanese yen/US dollar foreign currency hedge arrangement (as further described below, the “Currency Hedge Agreement”) put into place by the Company in connection with the transaction. Royalty payments are paid by Shionogi in Japanese yen, and any milestone payments will be paid in U.S. dollars. The Company’s collaboration with Shionogi was not impacted as a result of this transaction.

Non-Recourse Notes Payable

On March 9, 2011, Royalty Sub completed a private placement to institutional investors of $30,000 in aggregate principal amount of its PhaRMA Senior Secured 14.0% Notes due on December 1, 2020 (the “PhaRMA Notes”). The PhaRMA Notes were issued by Royalty Sub under an Indenture, dated as of March 9, 2011 (the “Indenture”), by and between Royalty Sub and U.S. Bank National Association, as Trustee. Principal and interest on the PhaRMA Notes issued are payable from, and are secured by, the rights to royalty and milestone payments under the Shionogi Agreement transferred by the Company to Royalty Sub and payments, if any, made to Royalty Sub under the Currency Hedge Agreement. The PhaRMA Notes bear interest at 14% per annum, payable annually in arrears on September 1st of each year. The Company remains entitled to receive any royalties and milestone payments related to sales of peramivir by Shionogi following repayment of the PhaRMA Notes.

Royalty Sub’s obligations to pay principal and interest on the PhaRMA Notes are obligations solely of Royalty Sub and are without recourse to any other person, including the Company, except to the extent of the Company’s pledge of its equity interests in Royalty Sub in support of the PhaRMA Notes. The Company may, but is not obligated to, make capital contributions to a capital account that may be used to redeem, or on up to one occasion pay any interest shortfall on, the PhaRMA Notes.

In September 2014, Royalty Sub was unable to pay the accrued interest obligation due September 3, 2013. Under the terms of the Indenture, Royalty Sub’s inability to pay the full amount of interest payable in September 2013 by the next succeeding payment date for the PhaRMA Notes, which was September 1, 2014, constituted an event of default. Accordingly, the PhaRMA Notes and related accrued interest have been classified as current liabilities on the December 31, 2014 balance sheet, and thereafter. As a result of the event of default under the PhaRMA Notes, the holders of the PhaRMA Notes may foreclose on the collateral securing the PhaRMA Notes and the equity interest in Royalty Sub and exercise other remedies available to them under the Indenture in respect of the PhaRMA Notes. In such event, the Company may not realize the benefit of future royalty payments that might otherwise accrue to it following repayment of the PhaRMA Notes and it might otherwise be adversely affected. Due to the non-recourse nature of the PhaRMA Notes, in the event of any potential foreclosure, the primary impact to the Company would be the loss of future royalty payments, if any, from Shionogi and legal costs associated with retiring the PhaRMA Notes. The PhaRMA Notes had a final legal maturity date of December 1, 2020, at which time the outstanding principal amount of the PhaRMA Notes of $30,000, together with accrued and unpaid interest of $20,614, was due in full.

Non-Recourse Notes Payable – Debt Extinguishment

During 2021, the royalty-bearing patents associated with RAPIACTA in Japan expired. Accordingly, the Company evaluated the current circumstances of the PhaRMA Notes, including (i) their non-recourse nature relative to the Company, (ii) the current state of default since September 1, 2014 and the legal maturity on December 1, 2020 and (iii) the loss of patent protection relative to RAPIACTA in Japan, upon which any significant repayment of the PhaRMA Notes is predicated. As a result, the Company determined that it was no longer the financial obligor, and as a result, the principal balance of $30,000 and associated accrued interest payable balance of $25,838 were written off, resulting in a gain on extinguishment recorded in other income (expense) for the year ended December 31, 2021.

ORLADEYO and Factor D Inhibitors

On December 7, 2020, the Company and RPI 2019 Intermediate Finance Trust (“RPI”) entered into a Purchase and Sale Agreement (the “2020 RPI Royalty Purchase Agreement”), pursuant to which the Company sold to RPI the right to receive certain royalty payments from the Company for a purchase price of $125,000 in cash (the “2020 RPI Royalty Sale”). Under the 2020 RPI Royalty Purchase Agreement, RPI is entitled to receive tiered, sales-based royalties on net product sales of ORLADEYO in the United States and certain key European markets (collectively, the “Key Territories”), and other markets where the Company sells ORLADEYO directly or through distributors (collectively, the “Direct Sales”) in an amount equal to: (i) 8.75% of aggregate annual net sales of ORLADEYO for annual net sales up to $350,000 and (ii) 2.75% of annual net sales for annual net sales between $350,000 and $550,000. No royalty payments are payable on annual Direct Sales over $550,000. In addition, RPI will be entitled to receive 1.0% of global net sales, if any, of BCX9930.

Under the 2020 RPI Royalty Purchase Agreement, RPI is also entitled to receive a tiered revenue share on ORLADEYO sublicense revenue or net sales by licensees outside of the Key Territories (the “Other Markets”) equal to: (i) 20% of the proceeds received by the Company for upfront license fees and development milestones for ORLADEYO in the Other Markets; (ii) 20% of proceeds received on annual net sales of up to $150,000 in the Other Markets; and (iii) 10% of proceeds received by the Company on annual net sales between $150,000 and $230,000 in the Other Markets. No royalty payments are payable on annual net sales above $230,000 in the Other Markets.

On November 19, 2021, the Company and RPI entered into (i) a Purchase and Sale Agreement (the “2021 RPI Royalty Purchase Agreement” and together with the 2020 RPI Royalty Purchase Agreement, the “RPI Royalty Purchase Agreements”), pursuant to which the Company sold to RPI the right to receive certain royalty payments from the Company for a purchase price of $150,000 in cash, and (ii) a Purchase and Sale Agreement with OCM IP Healthcare Holdings Limited, an affiliate of OMERS Capital Markets (“OMERS”) (the “OMERS Royalty Purchase Agreement” and collectively with the RPI Royalty Purchase Agreements, the “Royalty Purchase Agreements”), pursuant to which the Company sold to OMERS the right to receive certain royalty payments from the Company for a purchase price of an additional $150,000 in cash.

Under the 2021 RPI Royalty Purchase Agreement, RPI is entitled to receive tiered, sales-based royalties on Direct Sales in an amount equal to: (i) 0.75% of aggregate annual net sales of ORLADEYO for annual net sales up to $350,000 and (ii) 1.75% of annual net sales of ORLADEYO for annual net sales between $350,000 and $550,000. No royalty payments are payable on Direct Sales over $550,000. RPI is also entitled to receive a tiered revenue share on ORLADEYO sublicence revenue or net sales by licensees in the Other Markets in an amount equal to 3.0% of proceeds received by the Company on annual net sales of up to $150,000 in the Other Markets, and (iii) 2.0% of proceeds received by the Company on annual net sales between $150,000 and $230,000 in the Other Markets. No royalty payments are payable on annual net sales above $230,000 in the Other Markets.

Under the 2021 RPI Royalty Purchase Agreement, RPI is also entitled to receive tiered, sales-based royalties on net product sales of BCX9930 and another earlier stage Factor D inhibitor in an amount equal to: (i) 3.0% of worldwide aggregate annual net sales up to $1.5 billion and (ii) 2.0% of worldwide aggregate annual net sales between $1.5 billion and $3.0 billion. No royalty payments are payable on annual net sales above $3.0 billion. RPI is also entitled to receive tiered profit share amounts of up to 3.0% from certain other permitted sales in certain other markets.

The royalties payable under the 2021 RPI Royalty Purchase Agreement are in addition to the royalties payable to RPI under the 2020 RPI Royalty Purchase Agreement.

Under the OMERS Royalty Purchase Agreement, commencing with the calendar quarter beginning October 1, 2023, OMERS will be entitled to receive tiered, sales-based royalties on Direct Sales in an amount equal to: (i) 7.5% of aggregate annual net sales of ORLADEYO for annual net sales up to $350,000 and (ii) 6.0% of annual net sales of ORLADEYO for annual net sales between $350,000 and $550,000 (with no royalty payments payable on annual Direct Sales over $550,000) (the “Regime A Royalty Rate”). If annual Direct Sales for calendar year 2023 reach a specified amount set forth in the OMERS Royalty Purchase Agreement, then for each calendar quarter beginning on or after January 1, 2024, OMERS will be entitled to receive the Regime A Royalty Rate. If annual Direct Sales for calendar year 2023 are less than the specified amount, OMERS will be entitled to receive tiered, sales-based royalties on Direct Sales in an amount equal to: (i) 10.0% of aggregate annual net sales of ORLADEYO for annual net sales up to $350,000 and (ii) 3.0% of annual net sales of ORLADEYO for annual net sales between $350,000 and $550,000 (with no royalty payments payable on annual Direct Sales over $550,000) (the “Regime B Royalty Rate”).

Under the OMERS Royalty Purchase Agreement, OMERS is also entitled to receive a tiered revenue share on ORLADEYO sublicense revenue or net sales by licensees in the Other Markets in an amount equal to: (i) 20.0% of the proceeds received by the Company for upfront license fees and development milestones for ORLADEYO in the Other Markets, (ii) 20.0% of proceeds received by the Company on annual net sales of up to $150,000 in the Other Markets, and (iii) 10.0% of proceeds received by the Company on annual net sales between $150,000 and $230,000 in the Other Markets. No royalty payments are payable on annual net sales above $230,000 in the Other Markets. OMERS is also entitled to receive profit share amounts of up to 10% from certain other permitted sales in certain other markets.

Under the 2020 RPI Royalty Purchase Agreement, the Company is required to make royalty payments of amounts owed to RPI each calendar quarter following the first commercial sale of ORLADEYO in any country. Under the 2021 RPI Royalty Purchase Agreement, the Company is required to make payments to RPI in respect of net sales or sublicense revenue in each calendar quarter from and after October 1, 2021. Under the OMERS Royalty Purchase Agreement, the Company will be required to make payments to OMERS is respect of net sales or sublicense revenue in each calendar quarter from and after October 1, 2023. OMERS will no longer be entitled to receive any payments on the date in which aggregate payments actually received by OMERS equals either 142.5% or 155.0% of the $150,000 purchase price, depending on sales levels in calendar year 2023.

The transactions contemplated by each of the Royalty Purchase Agreements are referred to herein as the “Royalty Sales.”

Under the Royalty Purchase Agreements, the Company has agreed to specified affirmative and negative covenants, including covenants regarding periodic reporting of information by the Company to RPI and OMERS, third-party audits of royalties paid under the Royalty Purchase Agreements, and restrictions on the ability of the Company or any of its subsidiaries to incur indebtedness other than certain royalty sales and as is permitted to be incurred under the terms of the Company’s Credit Agreement with Athyrium Opportunities III Co-Invest 1 LP. Refer to Note 9 for further details on the Credit Agreement. The restrictions on the ability of the Company or any of its subsidiaries to incur indebtedness are eliminated after the achievement of certain specified milestones in the Royalty Purchase Agreements.

The cash consideration obtained pursuant to the Royalty Purchase Agreements is recorded in “Royalty financing obligations” on the Company’s consolidated balance sheet. The fair value for the royalty financing obligations at the time of the transactions was based on the Company’s estimates of future royalties expected to be paid to the counterparty over the life of the arrangement. The Company subsequently records the obligations at its carrying value using the effective interest method. In order to amortize the royalty financing obligation, the Company utilizes the prospective method to estimate the future royalties to be paid by the Company to the counterparty over the life of the arrangement. Under the prospective method, a new effective interest rate is determined based on the revised estimate of remaining cash flows. The new rate is the discount rate that equates the present value of the revised estimate of remaining cash flows with the carrying amount of the debt, and it will be used to recognize interest expense for the remaining periods. The Company periodically assesses the amount and timing of expected royalty payments using a combination of internal projections and forecasts from external sources. The estimates of future net product sales (and resulting royalty payments) are based on key assumptions including population, penetration, probability of success, and sales price, among others. To the extent such payments are greater or less than the Company’s initial estimates or the timing of such payments is materially different than its original estimates, the Company will prospectively adjust the amortization of the royalty financing obligations and the effective interest rate.

The following table shows the activity within the Royalty financing obligations account (in thousands) as well as the effective interest rate as of December 31, 2021:

	2020 RPI Royalty Agreement			2021 RPI Royalty Agreement			OMERS Royalty Agreement			Total
2020 Royalty sale: Royalty financing obligation, net of issuance costs	$	122,609		$	−		$	−		$	122,609
Non-cash Interest expense on Royalty financing obligation		2,108			−			−			2,108
Balance as of December 31, 2020	$	124,717		$	−		$	−		$	124,717
2021 Royalty sale: Royalty financing obligations, net of issuance costs		−			150,833			147,309			298,142
Non-cash Interest expense on Royalty financing obligations		33,308			2,897			1,465			37,670
Royalty revenues paid and payable		(10,801	)		(353	)		−			(11,154	)
Balance as of December 31, 2021	$	147,224		$	153,377		$	148,774		$	449,375

Effective interest rate		27.3	%		16.5	%		8.5	%

Deferred issuance costs pursuant to the Royalty financing obligations, which consist primarily of advisory and legal fees, totaled $8,497 and $2,370 as of December 31, 2021 and 2020, respectively. The Royalty financing obligation liabilities and the associated deferred issuance costs are amortized using the effective interest method over the term of the arrangement, in accordance with the respective guidance. Concurrent with entering into the 2021 RPI Royalty Purchase Agreement, the Company and RPI entered into a Common Stock Purchase Agreement, pursuant to which the Company sold common stock to RPI for a premium of $4,269. This premium has been deferred and is being amortized using the effective interest method over the term of the applicable arrangement. Refer to Note 11 for further details on the common stock sale premium.

Note 6 - Property and Equipment (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Depreciation, Depletion and Amortization, Total	$ 777	$ 748	$ 724

Note 8 - Royalty Monetizations (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Royalty Financing Obligations [Table Text Block]

	2020 RPI Royalty Agreement			2021 RPI Royalty Agreement			OMERS Royalty Agreement			Total
2020 Royalty sale: Royalty financing obligation, net of issuance costs	$	122,609		$	−		$	−		$	122,609
Non-cash Interest expense on Royalty financing obligation		2,108			−			−			2,108
Balance as of December 31, 2020	$	124,717		$	−		$	−		$	124,717
2021 Royalty sale: Royalty financing obligations, net of issuance costs		−			150,833			147,309			298,142
Non-cash Interest expense on Royalty financing obligations		33,308			2,897			1,465			37,670
Royalty revenues paid and payable		(10,801	)		(353	)		−			(11,154	)
Balance as of December 31, 2021	$	147,224		$	153,377		$	148,774		$	449,375

Effective interest rate		27.3	%		16.5	%		8.5	%

Note 13 - Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Balance	$ 8,230	$ 7,210
Additions to current period tax positions	1,499	1,020
Balance	$ 9,729	$ 8,230

Note 3 - Investments- Fair Value of the Company's Investments by Type (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost	$ 9,989	$ 28,211,000
Accrued Interest	65,000	25,000
Gross Unrealized Losses	(13,000)	(3,000)
Total investments	10,041,000	28,239,000
Gross Unrealized Gains		6,000
US Government Agencies Debt Securities [Member]
Amortized Cost	4,043,000	24,986,000
Accrued Interest	17,000	14,000
Gross Unrealized Losses	(7,000)	(3,000)
Total investments	4,053,000	25,000,000
Gross Unrealized Gains		3,000
Corporate Debt Securities [Member]
Amortized Cost	4,294,000
Accrued Interest	40,000
Gross Unrealized Losses	(5,000)
Total investments	4,329,000
Certificates of Deposit [Member]
Amortized Cost	1,652,000	3,225,000
Accrued Interest	8,000	11,000
Gross Unrealized Losses	(1,000)
Total investments	$ 1,659,000	3,239,000
Gross Unrealized Gains		$ 3,000

Note 14 - Employee 401(k) Plan (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 2,834	$ 1,569	$ 926

Note 4 - Trade Receivables

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Trade Receivables [Text Block]

Note 4 – Trade Receivables

Product Sales

Receivables from product sales are recorded for amounts due to the Company related to sales of ORLADEYO® and RAPIVAB®. At December 31, 2021 and 2020, receivables related to sales of ORLADEYO were $27,384 and $149, respectively. At December 31, 2021 and 2020, receivables related to sales of RAPIVAB were $49 and $254, respectively. No reserve or allowance amounts were recorded as of December 31, 2021 and December 31, 2020, respectively.

Collaborations

At December 31, 2021 and 2020, the Company had the following receivables from collaborations:

	December 31, 2021
	Billed		Unbilled		Total
U.S. Department of Health and Human Services, net	$	5	$	1,670	$	1,675
Royalty receivables from partners		305		−		305
Total receivables from collaborators	$	310	$	1,670	$	1,980

	December 31, 2020
	Billed		Unbilled		Total
U.S. Department of Health and Human Services, net	$	−	$	5,402	$	5,402
Royalty receivables from partners		2,816		25		2,841
Total receivables from collaborators	$	2,816	$	5,427	$	8,243

As of December 31, 2021, the Company maintained a reserve of $701 related to royalties associated with Green Cross. No reserve was recorded at December 31, 2020.

Note 12 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Years Ended December 31,
	2021		2020		2019
Research and development	$	20,179	$	10,222	$	13,977
Selling, general and administrative		14,461		4,572		3,742
Total stock-based compensation expense	$	34,640	$	14,794	$	17,719

Share-based Payment Arrangement, Activity [Table Text Block]

							Weighted
							Average
	*Awards*			*Options*			*Exercise*
	*Available*			*Outstanding*			*Price*
Balance at December 31, 2018		805			17,491		$	6.49
Plan amendment		4,000			−			−
Restricted stock awards granted		(27	)		−			−
Stock option awards granted		(4,511	)		4,511			3.91
Stock option awards exercised		−			(251	)		3.75
Stock option awards cancelled		701			(701	)		6.82
Balance at December 31, 2019		968			21,050		$	5.96
Plan amendment		8,000			−			−
Restricted stock awards granted		(31	)		−			−
Stock option awards granted		(7,469	)		7,469			8.06
Stock option awards exercised		−			(510	)		3.56
Stock option awards cancelled		3,124			(3,124	)		6.93
Balance at December 31, 2020		4,592			24,885		$	6.52
Plan amendment		7,500			−			−
Restricted stock units granted		(1,936	)		−			−
Stock option awards granted		(6,753	)		6,753
Stock option awards exercised		−			(2,705	)		4.36
Stock option awards cancelled		248			(248	)		7.62
Balance at December 31, 2021		3,651			28,685		$	7.90

							Weighted
							Average
	*Awards*			*Options*			*Exercise*
	*Available*			*Outstanding*			*Price*
Balance at December 31, 2020		229			4,171		$	3.88
Plan amendment		1,500			−			−
Stock option awards granted		(1,003	)		1,003			13.91
Stock option awards exercised		−			(592	)		3.63
Stock option awards cancelled		174			(174	)		3.67
Balance at December 31, 2021		900			4,408		$	6.20

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2021			2020			2019
Expected Life		5.5			5.5			5.5
Expected Volatility		84	%		84	%		81	%
Expected Dividend Yield		0.0	%		0.0	%		0.0	%
Risk-Free Interest Rate		1.1	%		0.4	%		1.8	%

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable [Table Text Block]

					Outstanding					Exercisable
						Weighted		Weighted				Weighted
						Average		Average				Average
						Remaining		Exercise				Exercise
Range				Number		Life		Price		Number		Price

$	0	to	3		1,874		5.9	$	2.30		1,158	$	2.12
	3	to	6		10,190		6.5		4.22		7,317		4.41
	6	to	9		10,599		8.2		7.89		4,317		7.56
	9	to	12		8,228		8.1		11.14		2,120		10.86
	12	to	15		1,291		6.8		13.10		535		12.31
	15	to	18		911		9.0		15.95		114		15.56
$	0	to	18		33,093		7.5	$	7.68		15,561	$	6.34

Share-based Payment Arrangement, Option, Activity [Table Text Block]

	Non-Vested Stock Option Awards			Weighted Average Grant-Date Fair Value
Balance December 31, 2020		16,020		$	4.25
Stock option awards granted		7,756			3.31
Stock option awards vested		(5,837	)		3.97
Stock option awards forfeited		(407	)		4.14
Balance December 31, 2021		17,532		$	3.86

Note 9 - Debt (Details Textual) - USD ($) $ in Thousands			1 Months Ended	12 Months Ended
Note 9 - Debt (Details Textual) - USD ($) $ in Thousands	Dec. 07, 2020	Feb. 05, 2019	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Jan. 01, 2020
Repayments of Lines of Credit					$ 52,420
Long-term Debt, Total			$ 122,609	$ 298,142	122,609
MidCap Financial Services, LLC [Member] \| Senior Credit Facility [Member]
Debt Instrument, Face Amount		$ 100,000
Repayments of Lines of Credit	$ 43,298
Debt Instrument, Basis Spread on Variable Rate		8.00%
Debt Instrument, Minimum LIBOR		0.50%
Debt Instrument, Term (Month)		30 months
Extinguishment of Debt, Amount			40,000
Payment for Debt Extinguishment or Debt Prepayment Cost			3,298
Write off of Deferred Debt Issuance Cost			$ 1,211		1,211
Credit Agreement [Member] \| Athyrium [Member]
Debt Instrument, Face Amount	$ 200,000
Debt Instrument, LIBOR Floor	1.75%
Debt Instrument, LIBOR Cap	3.50%
Debt Instrument, Exit Fee, Percentage of Principal	2.00%
Debt Instrument, Commitment Fee Percentage	1.00%
Long-term Debt, Gross				125,000
Paid-in-Kind Interest				16,009	1,056
Long-term Debt, Total				142,065
Debt Instrument, Interest Rate, Effective Percentage						12.17%
Credit Agreement [Member] \| Athyrium [Member] \| Prior to the Second Anniversary [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	102.00%
Debt Instrument, Prepayment Fee, Percentage of Accrued Interest	0.50%
Credit Agreement [Member] \| Athyrium [Member] \| Between the Second and Third Anniversaries [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	2.00%
Credit Agreement [Member] \| Athyrium [Member] \| Between the Third and Fourth Anniversaries [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	1.00%
Credit Agreement [Member] \| Athyrium [Member] \| After Fourth Anniversary [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	0.00%
Credit Agreement [Member] \| Athyrium [Member] \| Term Loan A Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	$ 15,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loan A and B Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	20,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loans A, B and C Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	15,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loans A, B and C Drawn and Cure Right Exercised [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	$ 20,000
Credit Agreement [Member] \| Athyrium [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	8.25%
Credit Agreement [Member] \| Athyrium [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| PIK Interest Payment is Made [Member]
Debt Instrument, Basis Spread on Variable Rate	10.25%
Credit Agreement [Member] \| Athyrium [Member] \| Term A Loan [Member]
Proceeds from Issuance of Long-term Debt, Total	$ 125,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total				8,483			$ 7,764
Amortization of Debt Issuance Costs				$ 531	$ 131
Credit Agreement [Member] \| Athyrium [Member] \| Term B Loan [Member]
Debt Instrument, Face Amount	25,000
Credit Agreement [Member] \| Athyrium [Member] \| Term C Loan [Member]
Debt Instrument, Face Amount	$ 50,000
Secured Credit Facility, First Tranche [Member] \| MidCap Financial Services, LLC [Member] \| Senior Credit Facility [Member]
Debt Instrument, Face Amount		$ 50,000
Repayments of Long-term Debt, Total		30,000
Secured Credit Facility, Second Tranche [Member] \| MidCap Financial Services, LLC [Member] \| Senior Credit Facility [Member]
Debt Instrument, Face Amount		30,000
Secured Credit Facility, Third Tranche [Member] \| MidCap Financial Services, LLC [Member] \| Senior Credit Facility [Member]
Debt Instrument, Face Amount		$ 20,000

Note 12 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			12 Months Ended
	Dec. 31, 2019	Dec. 31, 2014	Aug. 31, 2013	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement, Expense				$ 34,640	$ 14,794	$ 17,719
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)				7,756,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 3.31
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 107,852
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Expected to be Recognized Next Year				35,060
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Expected to be Recognized Year Two				30,375
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Expected to be Recognized Year Three				27,607
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Expected to be Recognized Year Four				$ 14,810
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)				321,000	246,000	115,000
Share-based Payment Arrangement, Option [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				1 year
Incentive Plan [Member]
Share-based Payment Arrangement, Expense				$ 27,062	$ 12,938	$ 17,164
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 7.93	$ 5.48	$ 2.63
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				$ 25,484	$ 1,562	$ 1,127
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	968,000			3,651,000	4,592,000	968,000	805,000
Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year)				10 years
Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Vest 25% Each Year Until Fully Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				4 years
Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Thirty-six Equal Monthly Installments [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				3 years
Incentive Plan [Member] \| Performance Shares [Member] \| August 2013 [Member]
Share-based Payment Arrangement, Expense					$ 1,768
Incentive Plan [Member] \| Performance Shares [Member] \| December 2019 [Member]
Share-based Payment Arrangement, Expense					684
Incentive Plan [Member] \| Performance Shares [Member] \| Vest Upon Successful Completion of Specific Development Milestones [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%	85.00%	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	315,000	1,250,000	1,032,000
Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 11.36
Inducement Plan [Member]
Share-based Payment Arrangement, Expense				$ 6,055	$ 1,494	$ 323
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 9.65	$ 2.73	$ 2.41
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)				10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				$ 6,700	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				900,000	229,000
Inducement Plan [Member] \| Vest 25% Each Year Until Fully Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				25.00%
Inducement Plan [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%
Employee Stock Purchase Plan [Member]
Share-based Payment Arrangement, Expense				$ 1,523	$ 362	$ 232
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 2.80	$ 1.47	$ 2.01
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)				7,975,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				6,052,000
Percentage of Salary to Purchase Common Stock, Maximum				15.00%
Percentage of Common Stock Shares, Beginning				85.00%
Percentage of Common Stock Shares, Ending				85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee (in shares)				3,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee, Amount				$ 25
Employee Stock Ownership Plan (ESOP), Weighted Average Purchase Price of Shares Purchased (in dollars per share)				$ 6.20	$ 2.56	$ 3.51
Incentive Plan and Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year)				5 years 8 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value				$ 116,811
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value				$ 23,395	$ 18,739	$ 12,499
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number (in shares)				30,268
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price (in dollars per share)				$ 7.64
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term (Year)				7 years 4 months 24 days

Note 13 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
Note 13 - Income Taxes (Details Textual) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 47,954,000	$ 38,551,000	$ 23,824,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	0	0	0
Undistributed Earnings of Foreign Subsidiaries	$ 750,000
Open Tax Year	2018 2019 2020 2021
Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	$ 80,925
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	$ 480,331,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total		$ 177,567,000
Foreign Tax Authority [Member]
Operating Loss Carryforwards, Total			$ 29,355,000

Note 13 - Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Net federal and state operating losses	$ 113,649	$ 159,939
Research and development credits	71,197	66,331
Royalty income	106,007	28,034
Stock-based compensation	14,512	10,732
Capitalized R&D	8,997
Leasing obligations	1,836	1,135
Other	4,809	5,563
Total deferred tax assets	321,007	271,734
Fixed assets	(607)	(124)
Right of use asset	(1,527)	(854)
Total deferred tax liabilities	(2,134)	(978)
Valuation allowance	(318,714)	$ (270,756)
Net deferred tax assets	$ 159

Note 13 - Income Taxes - Loss Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Domestic	$ (159,632)	$ (176,613)
Foreign	(22,177)	(6,201)
Loss before income taxes	$ (181,809)	$ (182,814)	$ (108,897)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123384075&loc=d3e41242-110953

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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+ Details

Note 1 - Significant Accounting Policies and Concentrations of Risk

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

Significant Accounting Policies [Text Block]

Note 1 — Significant Accounting Policies and Concentrations of Risk

The Company

BioCryst Pharmaceuticals, Inc. (the “Company”) is a commercial-stage biotechnology company that discovers novel, oral, small-molecule medicines. The Company focuses on the treatment of rare diseases in which significant unmet medical needs exist and an enzyme plays the key role in the biological pathway of the disease. The Company was founded in 1986 and incorporated in Delaware in 1991, and its headquarters is located in Durham, North Carolina. The Company integrates the disciplines of biology, crystallography, medicinal chemistry and computer modeling to discover and develop small molecule pharmaceuticals through the process known as structure-guided drug design.

The Company’s marketed products include oral, once-daily ORLADEYO® for the prevention of hereditary angioedema (“HAE”) attacks and RAPIVAB® (peramivir injection) for the treatment of acute uncomplicated influenza in the United States. ORLADEYO received regulatory approval in the United States in December 2020. During 2021, ORLADEYO received regulatory approvals in the European Union, Japan, the United Arab Emirates and the United Kingdom. The Company is commercializing ORLADEYO in each of these territories directly or through distributors, except in Japan where Torii Pharmaceuticals Co., Ltd. (“Torii”), the Company’s collaborative partner, has the exclusive right to commercialize ORLADEYO for the prevention of HAE attacks in exchange for certain milestone and royalty payments to us. In addition to its approval in the United States, peramivir injection has received regulatory approvals in Canada, Australia, Japan, Taiwan and Korea.

Based on the Company’s expectations for revenue, operating expenses, and the additional $75 million available to the Company under its existing credit facility, the Company believes its financial resources available at December 31, 2021 will be sufficient to fund its operations for at least the next 12 months. The Company has sustained operating losses for the majority of its corporate history and expects that its 2022 expenses will exceed its 2022 revenues. The Company expects to continue to incur operating losses and negative cash flows until revenues reach a level sufficient to support ongoing operations. The Company’s liquidity needs will be largely determined by the success of operations in regard to the successful commercialization of its products and the progression of its product candidates in the future. The Company regularly evaluates other opportunities to fund future operations, including: (1) securing or increasing U.S. Government funding of its programs, including obtaining procurement contracts; (2) out-licensing rights to certain of its products or product candidates, pursuant to which the Company would receive cash milestone payments; (3) raising additional capital through equity or debt financings or from other sources, including royalty or other monetization transactions; (4) obtaining additional product candidate regulatory approvals, which would generate revenue, milestone payments and cash flow; (5) reducing spending on one or more research and development programs, including by discontinuing development; and/or (6) restructuring operations to change its overhead structure. The Company may issue securities, including common stock, preferred stock, depositary shares, purchase contracts, warrants, debt securities and units, through private placement transactions or registered public offerings in the future. The Company’s future liquidity needs, and ability to address those needs, will largely be determined by the success of its products and product candidates, timing, scope and magnitude of its commercial expenses and key development and regulatory events and its decisions in the future.

Basis of Presentation

The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances among the consolidated entities have been eliminated from the consolidated financial statements.

The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). Such consolidated financial statements reflect all adjustments that are, in management’s opinion, necessary to present fairly, in all material respects, the Company’s consolidated financial position, results of operations, and cash flows. There were no adjustments other than normal recurring adjustments.

Reclassifications/Revisions

The Company has reclassified certain non-cash expense amounts on the Consolidated Statement of Cash Flows for the year ended December 31, 2020, to conform with the current year presentation. Additionally, the Company revised its Consolidated Statement of Cash Flows for the year ended December 31, 2020 to reflect an immaterial correction whereby net cash used in operating activities was revised from $(137,216) to $(135,108) and net cash provided by financing activities was revised from $302,697 to $300,589. The reclassifications and correction had no effect on net cash flows and no impact on the Consolidated Balance Sheet, Consolidated Statement of Comprehensive Loss, Consolidated Statement of Stockholders’ Equity (Deficit), or the net loss or loss per share for the year ended December 31, 2020.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. The most significant estimates in the Company’s consolidated financial statements relate to the valuation of stock options, the ORLADEYO royalty financing obligations and the valuation allowance for deferred tax assets resulting from net operating losses. These estimates are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates.

Revenue Recognition

Pursuant to Accounting Standards Codification (“ASC”) Topic 606, the Company recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, Topic 606 includes provisions within a five step model that includes i) identifying the contract with a customer, ii) identifying the performance obligations in the contract, iii) determining the transaction price, iv) allocating the transaction price to the performance obligations, and v) recognizing revenue when, or as, an entity satisfies a performance obligation.

At contract inception, the Company identifies the goods or services promised within each contract, assesses whether each promised good or service is distinct and determines those that are performance obligations. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied.

Product Sales, Net

The Company’s principal sources of product sales are sales of ORLADEYO, which the Company began shipping to patients in December 2020, sales of peramivir to the Company’s licensing partners and sales of RAPIVAB to the U.S. Department of Health and Human Services under the Company’s procurement contract. In the United States, the Company ships ORLADEYO directly to patients through a single specialty pharmacy, which is considered its customer. In the European Union, United Kingdom and elsewhere, the Company sells ORLADEYO to specialty distributors as well as hospitals and pharmacies, which collectively are considered its customers.

The Company recognizes revenue for sales when its customers obtain control of the product, which generally occurs upon delivery. For ORLADEYO, the Company classifies payments to its specialty pharmacy customer for certain services provided by its customer as selling, general and administrative expenses to the extent such services provided are determined to be distinct from the sale of its product.

Net revenue from sales of ORLADEYO is recorded at net selling price (transaction price), which includes estimates of variable consideration for which reserves are established for (i) estimated government rebates, such as Medicaid and Medicare Part D reimbursements, and estimated managed care rebates, (ii) estimated chargebacks, (iii) estimated costs of co-payment assistance programs and (iv) product returns. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable or as a current liability. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the applicable contract. The amount of variable consideration included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company's estimates. If actual results in the future vary from estimates, the Company adjusts these estimates, which would affect net product revenue and earnings in the period such variances become known.

Government and Managed Care Rebates. The Company contracts with government agencies and managed care organizations or, collectively, third-party payors, so that ORLADEYO will be eligible for purchase by, or partial or full reimbursement from, such third-party payors. The Company estimates the rebates it will provide to third-party payors and deducts these estimated amounts from total gross product revenues at the time the revenues are recognized. These reserves are recorded in the same period in which the revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability. The Company estimates the rebates that it will provide to third-party payors based upon (i) the Company's contracts with these third-party payors, (ii) the government mandated discounts applicable to government-funded programs, (iii) a range of possible outcomes that are probability-weighted for the estimated payor mix, and (iv) product distribution information obtained from the Company's specialty pharmacy.

Chargebacks. Chargebacks are discounts that occur when certain contracted customers, pharmacy benefit managers, insurance companies and government programs purchase directly from the Company’s specialty pharmacy. These customers purchase the Company’s product under contracts negotiated between them and the Company’s specialty pharmacy. The specialty pharmacy, in turn, charges back to the Company the difference between the price the specialty pharmacy paid and the negotiated price paid by the contracted customers, which may be higher or lower than the specialty pharmacy’s purchase price from the Company. The Company estimates chargebacks and adjusts gross product revenues and accounts receivable based on the estimates at the time revenues are recognized.

Co-payment assistance and patient assistance programs. Patients who have commercial insurance and meet certain eligibility requirements may receive co-payment assistance. Based upon the terms of the program and co-payment assistance utilization reports received from the specialty pharmacy, the Company is able to estimate the co-payment assistance amounts, which are recorded in the same period in which the related revenue is recognized, resulting in a reduction of product revenue. The Company also offers a patient assistance program that provides free drug product, for a limited period of time, to allow a patient’s insurance coverage to be established. Based on patient assistance program utilization reports provided by the specialty pharmacy, the Company records gross revenue of the product provided and a full reduction of the revenue amount for the free drug discount.

Product returns. The Company does not provide contractual return rights to its customer, except in instances where the product is damaged or defective. Non-acceptance by the patient of shipped drug product by the specialty pharmacy is reflected as a reversal of sales in the period in which the sales were originally recorded. Reserves for estimated non-acceptances by patients are recorded as a reduction of revenue in the period that the related revenue is recognized, as well as a reduction to accounts receivable. Estimates of non-acceptance are based on quantitative information provided by the specialty pharmacy.

Collaborative and Other Research and Development Arrangements and Royalties

The Company has collaboration and license agreements with a number of third parties, as well as research and development agreements with certain government entities. The Company’s primary sources of revenue from these collaborative and other research and development arrangements are license, service and royalty revenues.

Revenue from license fees, royalty payments, milestone payments, and research and development fees are recognized as revenue when the earnings process is complete and the Company has no further continuing performance obligations or the Company has completed the performance obligations under the terms of the agreement.

Arrangements that involve the delivery of more than one performance obligation are initially evaluated as to whether the intellectual property licenses granted by the Company represent distinct performance obligations. If they are determined to be distinct, the value of the intellectual property licenses would be recognized up front while the research and development service fees would be recognized as the performance obligations are satisfied. For performance obligations based on services performed, the Company measures progress using an input method based on the effort it expends or costs it incurs toward the satisfaction of the performance obligation in relation to the total estimated effort or costs. Variable consideration is assessed at each reporting period as to whether it is not subject to significant future reversal and, therefore, should be included in the transaction price at the inception of the contract. If a contract includes a fixed or minimum amount of research and development support, this also would be included in the transaction price. Changes to collaborations, such as the extensions of the research term or increasing the number of targets or technology covered under an existing agreement, are assessed for whether they represent a modification or should be accounted for as a new contract. For contracts with multiple performance obligations, revenue is allocated to each performance obligation based on its relative standalone selling price. Standalone selling prices are based on observable prices at which the Company separately sells the products or services. If a standalone selling price is not directly observable, then the Company estimates the standalone selling price using either an adjusted market assessment approach or an expected cost plus margin approach, representing the amount that the Company believes the market is willing to pay for the product or service. Analyzing the arrangement to identify performance obligations requires the use of judgment, and each may be an obligation to deliver services, a right or license to use an asset, or another performance obligation.

Milestone payments are recognized as licensing revenue upon the achievement of specified milestones if (i) the milestone is substantive in nature and the achievement of the milestone was not probable at the inception of the agreement; and (ii) the Company has a right to payment. Any milestone payments received prior to satisfying these revenue recognition criteria are recorded as deferred revenue.

Reimbursements received for direct out-of-pocket expenses related to research and development costs are recorded as revenue in the Consolidated Statements of Comprehensive Loss rather than as a reduction in expenses. Under the Company’s contracts with the Biomedical Advanced Research and Development Authority within the United States Department of Health and Human Services (”BARDA/HHS”) and the National Institute of Allergy and Infectious Diseases (“NIAID/HHS”), revenue is recognized as reimbursable direct and indirect costs are incurred.

Under certain of the Company’s license agreements, the Company receives royalty payments based upon its licensees’ net sales of covered products. Royalties are recognized at the later of when (i) the subsequent sale or usage occurs, or (ii) the performance obligation to which some or all of the sales-based or usage-based royalty has been satisfied.

Cash and Cash Equivalents

The Company generally considers cash equivalents to be all cash held in commercial checking accounts, certificates of deposit, money market accounts or investments in debt instruments with maturities of three months or less at the time of purchase. The carrying value of cash and cash equivalents approximates fair value due to the short-term nature of these items.

Restricted Cash

Restricted cash as of December 31, 2021 and 2020 reflects $1,924 and $796, respectively, in royalty revenue paid by Shionogi & Co., Ltd. (“Shionogi”) designated for interest on the PhaRMA Notes (defined in Note 8) and $1,421 and $1,425, respectively, the Company is required to maintain as collateral for a letter of credit associated with the lease execution and build-out of its new Birmingham research facilities.

Investments

The Company invests in high credit quality investments in accordance with its investment policy, which is designed to minimize the possibility of loss. The objective of the Company’s investment policy is to ensure the safety and preservation of invested funds, as well as maintaining liquidity sufficient to meet cash flow requirements. The Company places its excess cash with high credit quality financial institutions, commercial companies, and government agencies in order to limit the amount of its credit exposure. In accordance with its policy, the Company is able to invest in marketable debt securities that may consist of U.S. Government and government agency securities, money market and mutual fund investments, certificates of deposits, municipal and corporate notes and bonds, and commercial paper, among others. The Company’s investment policy requires it to purchase high-quality marketable securities with a maximum individual maturity of three years and requires an average portfolio maturity of no more than 12 months. Some of the securities the Company invests in may have market risk. This means that a change in prevailing interest rates may cause the principal amount of the investment to fluctuate. To minimize this risk, the Company schedules its investments with maturities that coincide with expected cash flow needs, thus avoiding the need to redeem an investment prior to its maturity date. Accordingly, the Company does not believe it has a material exposure to interest rate risk arising from its investments. Generally, the Company’s investments are not collateralized. The Company has not realized any significant losses from its investments.

The Company classifies all of its investments as available-for-sale. Unrealized gains and losses on investments are recognized in comprehensive loss, unless an unrealized loss is considered to be other than temporary, in which case the unrealized loss is charged to operations. The Company periodically reviews its investments for other than temporary declines in fair value below cost basis and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company believes the individual unrealized losses represent temporary declines primarily resulting from interest rate changes. Realized gains and losses are reflected in interest and other income in the Consolidated Statements of Comprehensive Loss and are determined using the specific identification method with transactions recorded on a settlement date basis. Investments with original maturities at date of purchase beyond three months and which mature at or less than 12 months from the balance sheet date are classified as current. Investments with a maturity beyond 12 months from the balance sheet date are classified as long-term. At December 31, 2021, the Company believes that the cost of its investments is recoverable in all material respects.

Trade Receivables

The majority of the Company’s trade receivables arise from product sales and primarily represent amounts due from our specialty pharmacy customer in the U.S. and other third-party distributors, hospitals and pharmacies in the European Union, United Kingdom and elsewhere and have standard payment terms that generally require payment within 30 to 90 days.

Receivables from collaborations are recorded for amounts due to the Company related to reimbursable research and development costs from the U.S. Department of Health and Human Services, and royalty receivables from our partners, including Shionogi, Green Cross, and Torii.

Monthly invoices are submitted to the U.S. Department of Health and Human Services related to reimbursable research and development costs. The Company is also entitled to monthly reimbursement of indirect costs based on rates stipulated in the underlying contract. The Company’s calculations of its indirect cost rates are subject to audit by the U.S. Government.

The Company does not adjust its receivables for the effects of a significant financing component at contract inception if it expects to collect the receivables in one year or less from the time of sale.

The Company provides reserves against trade receivables for estimated losses that may result from a customer's inability to pay. Receivables are evaluated to determine if any reserve or allowance should be recorded based on consideration of the current economic environment, expectations of future economic conditions, specific circumstances and the Company’s own historical collection experience. Amounts determined to be uncollectible are charged or written-off against the reserve.

Inventory

The Company values its inventories at the lower of cost or estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials, labor, manufacturing overhead, and shipping and handling costs on a first-in, first-out (FIFO) basis. Raw materials and work-in-process include all inventory costs prior to packaging and labelling, including raw material, active product ingredient, and the drug product. Finished goods include packaged and labelled products.

The Company’s inventories are subject to expiration dating. The Company regularly evaluates the carrying value of its inventories and provides valuation reserves for any estimated obsolete, short-dated or unmarketable inventories. In addition, the Company may experience spoilage of its raw materials and supplies. The Company’s determination that a valuation reserve might be required, in addition to the quantification of such reserve, requires it to utilize significant judgement.

The Company expenses costs related to the production of inventories as research and development expenses in the period incurred until such time it is believed that future economic benefit is expected to be recognized, which generally is reliant upon receipt of regulatory approval. Upon regulatory approval, the Company capitalizes subsequent costs related to the production of inventories.

Property and Equipment

Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Computer equipment is depreciated over a life of three years. Laboratory equipment, office equipment, and software are depreciated over a life of five years. Furniture and fixtures are depreciated over a life of seven years. Leasehold improvements are amortized over their estimated useful lives or the expected lease term, whichever is less.

In accordance with U.S. GAAP, the Company periodically reviews its property and equipment for impairment when events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written down to their estimated fair values. Property and equipment to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.

Accrued Expenses

The Company generally enters into contractual agreements with third-party vendors who provide research and development, manufacturing, distribution, and other services in the ordinary course of business. Some of these contracts are subject to milestone-based invoicing, and services are completed over an extended period of time. The Company records liabilities under these contractual commitments when it determines an obligation has been incurred, regardless of the timing of the invoice. This process involves reviewing open contracts and purchase orders, communicating with applicable Company personnel to identify services that have been performed on its behalf and estimating the level of service performed and the associated cost incurred for the service when the Company has not yet been invoiced or otherwise notified of actual cost. The majority of service providers invoice the Company monthly in arrears for services performed. The Company makes estimates of accrued expenses as of each balance sheet date in its financial statements based on the facts and circumstances. The Company periodically confirms the accuracy of its estimates with the service providers and makes adjustments if necessary. Examples of estimated accrued expenses include (i) fees paid to clinical research organizations (“CROs”) in connection with preclinical and toxicology studies and clinical trials; (ii) fees paid to investigative sites in connection with clinical trials; (iii) fees paid to contract manufacturers in connection with the production of the Company’s raw materials, drug substance, drug products, and product candidates; and (iv) professional fees.

The Company bases its expenses related to clinical trials on its estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and CROs that conduct and manage clinical trials on the Company’s behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. Payments under some of these contracts depend on factors such as the successful enrollment of patients and the completion of clinical trial milestones. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. As of December 31, 2021 and December 31, 2020, the carrying value of accrued expenses approximates their fair value due to their short-term settlement.

Cost of Product Sales

Cost of product sales includes the cost of producing and distributing inventories that are related to product revenue during the respective period, including freight. In addition, shipping and handling costs for product shipments are recorded as incurred. Finally, cost of product sales may also include costs related to excess or obsolete inventory adjustment charges.

Research and Development Expenses

The Company’s research and development costs are charged to expense when incurred. Research and development expenses include all direct and indirect development costs related to the development of the Company’s portfolio of product candidates. Advance payments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. Such amounts are recognized as expense when the related goods are delivered or the related services are performed. Research and development expenses include, among other items, personnel costs, including salaries and benefits, manufacturing costs, clinical, regulatory, and toxicology services performed by CROs, materials and supplies, and overhead allocations consisting of various administrative and facilities related costs. Most of the Company’s manufacturing and clinical and preclinical studies are performed by third-party CROs. Costs for studies performed by CROs are accrued by the Company over the service periods specified in the contracts, and estimates are adjusted, if required, based upon the Company’s ongoing review of the level of services actually performed.

Additionally, the Company has license agreements with third parties, such as Albert Einstein College of Medicine of Yeshiva University (“AECOM”), Industrial Research, Ltd. (“IRL”), and the University of Alabama at Birmingham (“UAB”), which require fees related to sublicense agreements or maintenance fees. The Company expenses sublicense payments as incurred unless they are related to revenues that have been deferred, in which case the expenses are deferred and recognized over the related revenue recognition period. The Company expenses maintenance payments as incurred.

Deferred collaboration expenses represent sub-license payments, paid to the Company’s academic partners upon receipt of consideration from various commercial partners, and other consideration paid to the Company’s academic partners for modification to existing license agreements. These deferred expenses would not have been incurred without receipt of such payments or modifications from the Company’s commercial partners and are being expensed in proportion to the related revenue being recognized. The Company believes that this accounting treatment appropriately matches expenses with the associated revenue.

Selling, General and Administrative Expenses

Selling, general and administrative expense is primarily comprised of compensation and benefits associated with sales and marketing, finance, human resources, legal, information technology and other administrative personnel. Additionally, selling, general and administrative expenses are comprised of market research, marketing, advertising and legal expenses, including patent costs, licenses and other general and administrative costs,

Advertising expenses related to ORLADEYO were $5,705 and $6,567 for the years ended December 31, 2021 and 2020, respectively. The Company did not incur advertising and product promotion expenses in 2019.

The Company seeks patent protection on all internally developed processes and products. All patent related costs are expensed to selling, general and administrative expenses when incurred as recoverability of such expenditures is uncertain.

Leases

The Company leases certain assets under operating leases, which primarily consisted of real estate leases, laboratory equipment leases and office equipment leases as of December 31, 2021. The Company accounts for lease obligations in accordance with ASU 2016-02: Leases (Topic 842), which requires a lessee to recognize a right-of-use asset and a lease liability on its balance sheet for most operating leases.

Certain of the Company’s operating leases provide for renewal options, which can vary by lease. The right-of-use asset and lease liabilities on the Company’s Consolidated Balance Sheet represent payments over the lease term, which includes renewal options for certain real estate leases that we are likely to exercise. As part of the Company’s assessment of the lease term, the Company elected the hindsight practical expedient, which allows companies to use current knowledge and expectations when determining the likelihood to extend lease options. Certain operating leases include rent escalation provisions, which the Company recognizes as expense on a straight-line basis. Lease expense for leases with an initial term of twelve months or less was not material.

The discount rate used in the calculation of the Company’s right-of-use asset and lease liability was determined based on the stated rate within each contract when available, or the Company’s collateralized borrowing rate from lending institutions.

The Company has not made any residual value guarantees related to its operating leases; therefore, the Company has no corresponding liability recorded on its Consolidated Balance Sheets.

Stock-Based Compensation

All share-based payments, including grants of stock option awards and restricted stock unit awards, are recognized in the Company’s Consolidated Statements of Comprehensive Loss based on their fair values. The fair value of stock option awards is estimated using the Black-Scholes option pricing model. The fair value of restricted stock unit awards is based on the grant date closing price of the common stock. Stock-based compensation cost is recognized as expense on a straight-line basis over the requisite service period of the award. In addition, we have outstanding performance-based stock options for which no compensation expense is recognized until “performance” is deemed to have occurred.

Interest Expense and Deferred Financing Costs

Interest expense for the years ended December 31, 2021, 2020 and 2019 was $59,294, $14,501 and $11,892, respectively, and primarily relates to the royalty financing obligations and PhaRMA Notes (Note 8), the secured term loan borrowing from the Credit Agreement and the senior credit facility (Note 9). Costs directly associated with the borrowings have been capitalized and are netted against the corresponding debt liabilities on the Consolidated Balance Sheets. These costs are being amortized to interest expense over the terms of the corresponding borrowings using the effective interest rate method. Amortization of deferred financing costs included in interest expense was $(531), $1,217 and $1,278 for the years ended December 31, 2021, 2020 and 2019, respectively.

In December 2021, the PhaRMA Notes and associated accrued interest payable was written-off into other income as a debt extinguishment (Refer to Note 8, Non-Recourse Notes Payable – Debt Extinguishment for additional information regarding the debt extinguishment). In December 2020, the outstanding principal balance of the senior credit facility was repaid and related unamortized deferred financing costs and original issue discount of $1,211 were fully expensed as part of loss on debt extinguishment.

Interest Expense and Royalty Financing Obligations

The royalty financing obligations are eligible to be repaid based on royalties from net sales of ORLADEYO, BCX9930, and another earlier stage Factor D inhibitor. Interest expense is accrued using the effective interest rate method over the estimated period each of the related liabilities will be paid. This requires the Company to estimate the total amount of future royalty payments to be generated from product sales over the life of the agreement. The Company imputes interest on the carrying value of each of the royalty financing obligations and records interest expense using an imputed effective interest rate. The Company reassesses the expected royalty payments each reporting period and accounts for any changes through an adjustment to the effective interest rate on a prospective basis. The assumptions used in determining the expected repayment term of the debt and amortization period of the issuance costs requires that the Company make estimates that could impact the carrying value of each of the liabilities, as well as the periods over which associated issuance costs will be amortized. A significant increase or decrease in forecasted net sales could materially impact each of the liability balances, interest expense and the time periods for repayment.

Currency Hedge Agreement

In connection with the issuance by JPR Royalty Sub LLC of the PhaRMA Notes, the Company entered into a Currency Hedge Agreement to hedge certain risks associated with changes in the value of the Japanese yen relative to the U.S. dollar. The final tranche of the options under the Currency Hedge Agreement expired in November 2020. The Currency Hedge Agreement did not qualify for hedge accounting treatment; therefore mark-to-market adjustments were recognized in the Company’s Consolidated Statements of Comprehensive Loss.

Cumulative mark-to-market adjustments for the years ended December 31, 2020 and 2019 resulted in losses of $632 and $347, respectively. Mark-to-market adjustments were determined by a third-party pricing model which uses quoted prices in markets that are not actively traded and for which significant inputs are observable directly or indirectly, representing Level 2 in the fair value hierarchy as defined by U.S. GAAP. In addition, realized currency exchange gains of $662 and $863 were recognized in 2020 and 2019, respectively, related to the exercise of a U.S. dollar/Japanese yen currency option under the Company’s foreign currency hedge.

Income Taxes

The liability method is used in the Company’s accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse.

Net Loss Per Share

Net loss per share is based upon the weighted average number of common shares outstanding during the period. Diluted loss per share is equivalent to basic net loss per share for all periods presented herein because common equivalent shares from unexercised stock options, warrants and common shares expected to be issued under the Company’s equity compensation plans were anti-dilutive. The calculation of diluted earnings per share for the years ended December 31, 2021, 2020, and 2019 does not include 26,034, 14,957, and 2,805, respectively, of potential common shares as their impact would be anti-dilutive.

Accumulated Other Comprehensive Income

Accumulated other comprehensive income is comprised of cumulative foreign currency translation adjustments and unrealized gains and losses on available-for-sale investments and is disclosed as a separate component of stockholders’ equity. Realized gain and loss amounts on available-for-sale investments are reclassified from accumulated other comprehensive loss and recorded as interest and other income on the Consolidated Statements of Comprehensive Loss. For both the years ended December 31, 2021 and 2020, realized gains of $1 were reclassified out of accumulated other comprehensive income.

Significant Customers and Other Risks

Significant Customers

The Company’s primary sources of revenue and cash flow are the sales of ORLADEYO to a specialty pharmacy, the reimbursement of galidesivir (formerly BCX4430) development expenses earned under cost-plus-fixed-fee contracts with BARDA/HHS and NIAID/HHS and sales of RAPIVAB (peramivir injection) under our procurement contract with the Assistant Secretary for Preparedness and Response within the United States Department of Health and Human Services.

ORLADEYO is distributed through an arrangement with a single specialty pharmacy in the U.S. The specialty pharmacy subsequently sells ORLADEYO to its customers (pharmacy benefit managers, insurance companies, government programs and group purchasing organizations) and dispenses product to patients. The specialty pharmacy’s inability or unwillingness to continue these distribution activities could adversely impact the Company’s business, results of operations and financial condition.

The Company relies on BARDA/HHS and NIAID/HHS to reimburse predominantly all of the development costs for its galidesivir program and stockpiling sales of RAPIVAB to HHS. Accordingly, reimbursement of these expenses represents a significant portion of the Company’s collaborative and other research and development revenues. Additionally, HHS is the primary customer for RABIVAB. The completion or termination of the NIAID/HHS and BARDA/HHS galidesivir contracts or the reduction or stoppage of purchases of RAPIVAB by HHS could adversely impact the Company’s business, results of operations and financial condition.

Further, the Company’s drug development activities are performed by a limited group of third-party vendors. If any of these vendors were unable to perform its services, this could significantly impact the Company’s ability to complete its drug development activities.

Risks from Third-Party Manufacturing and Distribution Concentration

The Company relies on single source manufacturers for active pharmaceutical ingredient and finished drug product manufacturing of product candidates in development and on a single specialty pharmacy for distribution of approved drug product in the US. Delays in the manufacture or distribution of any product could adversely impact the commercial revenue and future procurement stockpiling of the Company’s product candidates.

Credit Risk

Cash equivalents and investments are financial instruments that potentially subject the Company to concentration of risk to the extent recorded on the Consolidated Balance Sheets. The Company deposits excess cash with major financial institutions in the United States. Balances may exceed the amount of insurance provided on such deposits. The Company believes it has established guidelines for investment of its excess cash relative to diversification and maturities that maintain safety and liquidity. To minimize the exposure due to adverse shifts in interest rates, the Company maintains a portfolio of investments with an average maturity of approximately 12 months or less.

The Company’s receivables from sales of ORLADEYO are primarily due from one customer, resulting in a concentration of credit risk. Sales of ORLADEYO from the Company to the specialty pharmacy only occur once an order of product has been received by the specialty pharmacy from one of its customers, which include pharmacy benefit managers, insurance companies, government programs and group purchasing organizations.

The majority of the Company’s receivables from collaborations are due from the U.S. Government, for which there is no assumed credit risk.

Recently Adopted Accounting Pronouncements

In December 2019, the FASB issued ASU No. 2019-12 (ASC Topic 740), Simplifying the Accounting for Income Taxes. ASU 2019-12 simplifies accounting for income taxes by removing certain exceptions to the general principles and clarifying existing guidance. This standard is effective for fiscal years, and interim periods within those years, beginning after December 15, 2020. The adoption of this standard did not have a material impact to the Company’s financial position, results of operations or cash flows.

The Company has reviewed other new accounting pronouncements that were issued as of December 31, 2021 and does not believe that these pronouncements are either applicable to the Company, or that they will have a material impact on its financial position or results of operations.

Note 9 - Debt	12 Months Ended
Note 9 - Debt	Dec. 31, 2021
Credit Agreement [Member]
Notes to Financial Statements
Debt Disclosure [Text Block]	Note 9 — Debt Credit Agreement On December 7, 2020, the Company entered into a $200,000 Credit Agreement with Athyrium Opportunities III Co-Invest 1 LP (“Athyrium”), as lender and as administrative agent for the lenders. BioCryst Ireland Limited and BioCryst US Sales Co., LLC, each of which is a wholly-owned subsidiary of the Company, and BioCryst UK Limited, a wholly-owned subsidiary of BioCryst Ireland Limited, are guarantors to the Credit Agreement. The Credit Agreement provides for an initial term loan in the principal amount of $125,000 (the “Term A Loan”), which was received by the Company on December 7, 2020 and is recorded in “Secured term loan” on the Company’s balance sheet as of December 31, 2021. The Company used a portion of the proceeds from the Term A Loan to repay $43,298 of outstanding indebtedness, including accrued interest, under its existing credit facility with MidCap Financial Trust. The Credit Agreement also provides for two additional term loans, at the Company's option, in the respective principal amounts of $25,000 (the “Term B Loan”) and $50,000 (the “Term C Loan”). The Term B Loan and the Term C Loan may be drawn upon if, among other conditions, the Company reaches defined revenue milestones and, with respect to a draw on the Term C Loan, the Term B Loan has been funded prior to or contemporaneously with the Term C Loan. The maturity date of the Credit Agreement is December 7, 2025. On November 19, 2021, the Company entered into an amendment to the Credit Agreement (i) to permit the Company to enter into the 2021 RPI Royalty Purchase Agreement, the OMERS Royalty Purchase Agreement, and the other definitive documentation related thereto and to perform its obligations thereunder; (ii) to require the Company to pay to Athyrium, for the account of the lenders, a make-whole premium plus certain fees set forth in the Credit Agreement in the event that the Company does not draw the Term B Loan or the Term C Loan, as applicable, by the end of the applicable period available to draw the Term B Loan or the Term C Loan, subject to certain exceptions set forth in the Credit Agreement; and (iii) to require the Company to pay to Athyrium, for the account of the lenders, a make-whole premium plus certain fees set forth in the Credit Agreement in the event that the Company either (x) terminates the commitments in respect of the Term B Loan or the Term C Loan, as applicable, on or prior to the end of the applicable period available to draw the Term B Loan or the Term C Loan, or (y) prepays or repays, or is required to prepay or repay, voluntarily or pursuant to mandatory prepayment obligation under the Credit Agreement (e.g., with the proceeds of certain asset sales, certain ORLADEYO out-licensing or royalty monetization transactions (excluding the Royalty Sales), extraordinary receipts, debt issuances, or upon a change of control of the Company and specified other events, subject to certain exceptions), all of the then-outstanding Term Loans, in each case, subject to certain exceptions set forth in the Credit Agreement. The Credit Agreement provides for quarterly interest-only payments until the maturity date, with the unpaid principal amount of the outstanding Term Loans due and payable on the maturity date. For each of the first eight full fiscal quarters following December 7, 2020, the Company has the option to make the applicable interest payment-in-kind (a “PIK Interest Payment”) by capitalizing the entire amount of interest accrued during the applicable interest period with the unpaid original principal amount outstanding on the last day of such period. The Term Loans will bear interest at a rate equal to the three-month LIBOR rate, which shall be no less than 1.75% and no more than 3.50% (“LIBOR”), plus 8.25%, or for each interest period in which a PIK Interest Payment is made, the LIBOR plus 10.25%. Subject to certain exceptions, the Company is required to make mandatory prepayments of the Term Loans with the proceeds of certain asset sales, certain ORLADEYO out-licensing or royalty monetization transactions (excluding the Royalty Sale), extraordinary receipts, debt issuances, or upon a change of control of the Company and specified other events, subject to certain exceptions. The Company may make voluntary prepayments in whole or in part. Prepayments are subject to a premium equal to, (i) with respect to any voluntary prepayment and certain mandatory prepayments paid on or prior to the second anniversary of the applicable Term Loan borrowing date, the amount, if any, by which (a) the sum of (1) 102.00% of the principal amount of the Term Loan being prepaid plus (2) the present value of all interest that would have accrued on the principal amount of the Term Loan being prepaid through and including the second anniversary of the date of the borrowing of such Term Loan, plus 0.50%, exceeds (b) the principal amount of the Term Loan being prepaid; (ii) with respect to any prepayment made between the second and third anniversaries of the applicable Term Loan borrowing date, 2.00% of the principal amount of the Term Loan being prepaid; (iii) with respect to any prepayment made between the third and fourth anniversaries of the applicable Term Loan borrowing date, 1.00% of the principal amount of the Term Loan being prepaid; and (iv) with respect to any prepayment made after the fourth anniversary of the applicable Term Loan borrowing date, 0.00% of the principal amount of the Term Loan being prepaid. Upon the prepayment or repayment, including at maturity, of all or any of the Term Loans, the Company is obligated to pay an exit fee in an amount equal to 2.00% of the principal amount of the Term Loans prepaid or repaid. In addition, each Term Loan is subject to a 1.00% commitment fee at its respective borrowing date. The Credit Agreement also contains representations and warranties and affirmative and negative covenants customary for financings of this type, as well as customary events of default. Certain of the customary negative covenants limit the ability of the Company and certain of its subsidiaries to, among other things, grant liens, make investments, incur additional indebtedness, engage in mergers, acquisitions, and similar transactions, dispose of assets, license certain property, distribute dividends, make certain restricted payments, change the nature of the Company's business, engage in transactions with affiliates and insiders, prepay other indebtedness, or engage in sale and leaseback transactions, subject to certain exceptions. Additionally, as of the last day of each fiscal quarter (a “Test Date”), beginning with the first Test Date occurring immediately after the Term C Loan is drawn, if applicable, the Company may not permit consolidated net revenues from ORLADEYO sales in the United States for the four-fiscal quarter period ending on such Test Date to be less than the specified amounts set forth in the Credit Agreement (collectively, the “Revenue Tests”). If the Company fails to satisfy the Revenue Tests as of any Test Date, it will have a one-time right (the “Cure Right”) to repay in full the entire amount of the Term C Loans outstanding at such time together with all accrued and unpaid interest thereon plus the prepayment premium, exit fee, and any other fees or amounts payable under the Credit Agreement at such time. In addition, the Credit Agreement contains a minimum liquidity covenant requiring the Company to maintain at all times, as applicable, at least $15,000 of unrestricted cash and cash equivalents if only the Term A Loan has been drawn; at least $20,000 of unrestricted cash and cash equivalents if the Term B Loan has been drawn but the Term C Loan has not been drawn; and at least $15,000 (or, if the Cure Right has been exercised, $20,000) of unrestricted cash and cash equivalents if the Term C Loan has been drawn, subject to certain exceptions. A failure to comply with the covenants in the Credit Agreement could permit the Lenders under the Credit Agreement to declare the outstanding principal as well as accrued interest and fees, to be immediately due and payable. The Company's obligations under the Credit Agreement are secured by a security interest in, subject to certain exceptions, substantially all of the Company's assets. As of December 31, 2021, the Company had borrowings of $125,000 under the Credit Agreement. Quarterly interest payments under the Credit Agreement for the years ended December 31, 2021 and 2020, totaled $16,009 and $1,056, respectively, and have been designated and accounted for as PIK Interest Payments and added to the outstanding principal balance of the borrowing. As of December 31, 2021, borrowings, including the PIK Interest Payments totaled $142,065. The principal balance of the borrowing, including PIK amounts are accruing interest at a rate of 12.17%. The fair value of the debt approximates its carrying value based on prevailing interest rates as of the balance sheet date and is considered as Level 2 in the fair value hierarchy. As of December 31, 2021 and 2020, deferred debt fees and issuance costs totaled $8,483 and $7,764, respectively and are being amortized as interest expense on an effective interest rate method over the term of the Term A Loan. When utilizing the effective interest method, in periods in which PIK interest is designated and those amounts are added to the outstanding principal balance of the borrowing, the amortization of the deferred debt fees and issuance costs is accretive. Deferred financing amortization of ($531) and ($131), was recognized for the years ended December 31, 2021 and 2020, respectively. The Credit Agreement contains two provisions that, if deemed probable, would create the recognition of an embedded feature; however, at this time, the Company does not believe either provision is probable. Senior Credit Facility On February 5, 2019, the Company entered into a $100,000 Senior Credit Facility with an affiliate of MidCap Financial Services, LLC, as administrative agent (the “Second Amended and Restated Senior Credit Facility”). Borrowings under the Second Amended and Restated Senior Credit Facility were available in three tranches, with (i) the first tranche comprised of $50,000 funded at closing, which included $30,000 of proceeds that were deemed rolled over from the outstanding principal amount under the Company’s prior credit agreement, (ii) the second tranche comprised of $30,000, and (iii) the third tranche comprised of $20,000, with the second and third tranches to have been funded upon the completion of certain contingencies related to the Company’s development activities of its product candidates and the establishment of certain financial covenants. On September 10, 2019 the Company executed the first amendment to the Second Amended and Restated Credit Facility which extended the commitment termination date for the second tranche to November 30, 2019. On November 30, 2019, the Company’s access to the second tranche expired. The Second Amended and Restated Senior Credit Facility refinanced and replaced the Amended and Restated Senior Credit Facility dated as of July 20, 2018 (the “Amended and Restated Senior Credit Facility”). The Second Amended and Restated Senior Credit Facility had a variable interest rate of LIBOR (which was not to be less than 0.5%) plus 8%. The Second Amended and Restated Senior Credit Facility included an interest-only payment period through June 2020 and scheduled monthly principal and interest payments for the subsequent 30 months. The Company used a portion of the proceeds of the Second Amended and Restated Senior Credit Facility to pay off outstanding amounts under the Amended and Restated Senior Credit Facility and the remainder was used for general corporate purposes. In December 2020, the Company repaid the outstanding principal of the Second Amended and Restated Senior Credit Facility of $40,000 along with exit fees and accrued interest through the payoff date that totaled $3,298. The unamortized deferred financing cost and original issue discount of $1,211 was expensed as a loss on debt extinguishment.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details