0001437749-22-004354 | 10-K | XBRL Viewer

Subsequent Events [Text Block]

NOTE 19. Subsequent Events

Since December 31, 2021, the Company has issued 216,000 shares of common stock under the September 2021 ATM (see Note 1) for net proceeds totaling $1.0 million.

Changes in the status of litigation since December 31, 2021, are included in “Note 10. Commitments and Contingencies—(c) Litigation”.

Note 5 - Balance Sheet Components - Right-of-use Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Right-of-use assets, net	$ 13,168	$ 6,838
Facilities [Member]
Right-of-use assets, net	13,168	6,836
Office Equipment [Member]
Right-of-use assets, net	$ 0	$ 2

Note 12 - Equity Incentive Plans - Assumptions of Options (Details) - Share-based Payment Arrangement, Option [Member]	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Dividend yield	0.00%	0.00%	0.00%
Minimum [Member]
Risk-free interest rate	0.91%	0.40%	1.68%
Expected term (in years) (Year)	5 years 5 months 8 days	5 years 2 months 19 days	5 years 4 months 20 days
Expected volatility	122.00%	94.00%	83.00%
Maximum [Member]
Risk-free interest rate	1.35%	0.88%	2.31%
Expected term (in years) (Year)	6 years 29 days	10 years	10 years
Expected volatility	131.00%	111.00%	85.00%

Note 17 - Net Loss Per Share Attributable to Common Stockholders - Calculation of Basic and Diluted Net (Loss) Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net loss	$ (20,764)	$ (17,583)	$ (16,116)	$ (16,007)	$ (13,861)	$ (8,085)	$ (8,977)	$ (1,297)	$ (6,409)	$ (5,260)	$ (5,637)	$ (1,339)	$ (70,470)	$ (32,220)	$ (18,645)
Shares used to compute net loss per share – basic and diluted (in shares)													121,453,723	88,295,762	21,569,523
Net loss per share – basic and diluted (in dollars per share)	$ (0.17)	$ (0.14)	$ (0.13)	$ (0.14)	$ (0.13)	$ (0.08)	$ (0.12)	$ (0.02)	$ (0.13)	$ (0.32)	$ (0.39)	$ (0.18)	$ (0.58)	$ (0.36)	$ (0.86)

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

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Note 3 - Business Combination (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]

Property and equipment	$	321
Goodwill		4,508

Total purchase price	$	4,829

Note 1 - Organization and Basis of Presentation (Details Textual) - USD ($)								1 Months Ended	3 Months Ended	12 Months Ended			15 Months Ended	22 Months Ended	26 Months Ended	27 Months Ended	33 Months Ended
	Sep. 15, 2021	Oct. 13, 2020	Jul. 13, 2020	Mar. 02, 2020	Sep. 30, 2019	Apr. 11, 2019	Mar. 20, 2019	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2021	Dec. 03, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2021	Jun. 08, 2020	Jun. 07, 2020
Stock Issued During Period, Shares, New Issues (in shares)							1,200,000
Gross Proceeds from Issuance of Common Stock							$ 3,000,000.0
Proceeds from Issuance of Common Stock							2,500,000			$ 0	$ 9,175,000	$ 2,540,000
Payments of Stock Issuance Costs							$ 320,000
Proceeds from Warrant Exercises										1,849,000	25,951,000	180,000
Payments for Aggregate Commissions to Underwriters						$ 750,000
Proceeds From Exercise of Pre-funded Warrants										$ 0	$ 0	1,226,000
Common Stock, Par or Stated Value Per Share (in dollars per share)									$ 0.0001	$ 0.0001	$ 0.0001		$ 0.0001	$ 0.0001		$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.10
Common Stock, Shares Authorized (in shares)									150,000,000	150,000,000	150,000,000		150,000,000	150,000,000		150,000,000	150,000,000	150,000,000	150,000,000	100,000,000
Stock Issued During Period, Value, New Issues												2,440,000
The April 2019 Offering [Member]
Stock Issued During Period, Shares, New Issues, Excluding Shares Sold to Underwriters (in shares)						925,455
Shares Issued, Price Per Share (in dollars per share)						$ 1.10
Proceeds from Issuance or Sale of Equity, Total						$ 9,300,000
Proceeds from Issuance or Sale of Equity, Net						$ 8,100,000
The September 2019 Offering [Member]
Stock Issued During Period, Shares, New Issues, Excluding Shares Sold to Underwriters (in shares)					26,124,828
Shares Issued, Price Per Share (in dollars per share)					$ 0.30
Pre-funded Warrant Price (in dollars per share)					0.20
Pre-funded Warrant, Accompanying Warrant, Amount Paid Per Share (in dollars per share)					$ 0.10
Payments for Aggregate Commissions to Underwriters					$ 713,000
Proceeds from Issuance or Sale of Equity, Total					8,700,000
Proceeds from Issuance or Sale of Equity, Net					$ 7,700,000
The March 2020 Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)				4,000,000
Payments of Stock Issuance Costs				$ 775,000
Proceeds from Issuance or Sale of Equity, Total				10,000,000.0
Proceeds from Issuance or Sale of Equity, Net				$ 9,200,000
ATM Program [Member]
Stock Issued During Period, Shares, New Issues (in shares)			12,503,806
Proceeds from Issuance of Common Stock			$ 97,000,000.0							$ 122,210,000	$ 101,934,000	$ 0
Stock Issued During Period, Value, New Issues			$ 100,000,000.0
Open Market Sale Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)									692,651
Proceeds from Issuance of Common Stock									$ 4,900,000
Payments of Stock Issuance Costs		$ 300,000
Stock Issued During Period, Value, New Issues									$ 5,500,000
Open Market Sale Agreement, Maximum Aggregate Offering Price		$ 250,000,000
Open Market Sale Agreement, Sales Commission, Percentage		4.50%
The October 2020 Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)										13,239,839			13,932,490
Proceeds from Issuance of Common Stock										$ 127,900,000			$ 133,400,000
Proceeds from Issuance of Common Stock, Net										$ 122,200,000			$ 127,100,000
The September 2021 ATM [Member]
Stock Issued During Period, Shares, New Issues (in shares)								0
Payments of Stock Issuance Costs	$ 200,000
Open Market Sale Agreement, Maximum Aggregate Offering Price	$ 100,000,000
Open Market Sale Agreement, Sales Commission, Percentage	3.00%
Warrants in Connection with March 2019 Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)							84,000
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)							1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)							$ 3.125
Warrants and Rights Outstanding, Term (Year)							5 years
Warrants and Rights Outstanding							$ 100,000
Common Stock Warrants [Member]
Proceeds from Warrant Exercises																		$ 200,000
Class of Warrant or Right, Exercised During Period (in shares)																	10,410,398	67,825
Proceeds from Exercise of Common Stock Warrants																	$ 11,500,000
Warrants in Connection With the April 2019 Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						10,454,546
Warrants and Rights Outstanding						$ 333,000
Class of Warrant Right, Number of Pre-funded Warrants Issued During Period (in shares)						8,165,455
Pre-funded Warrant Price (in dollars per share)						$ 1.00
Pre-funded Warrant, Accompanying Warrant, Amount Paid Per Share (in dollars per share)						$ 0.10
Warrants in Connection With the April 2019 Offering [Member] \| Over-Allotment Option [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						1,363,636
Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)					1	1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)					$ 0.10	$ 0.10
Class of Warrant or Right, Exercised During Period (in shares)																4,100,000	8,165,455
Class of Warrant Right, Number of Pre-funded Warrants Issued During Period (in shares)					4,100,000
Proceeds From Exercise of Pre-funded Warrants																$ 400,000	$ 800,000
Common Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)					1	1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)					$ 0.30	$ 1.10
Warrants and Rights Outstanding, Term (Year)					5 years	5 years
Class of Warrant or Right, Exercised During Period (in shares)																30,661,667
Proceeds from Exercise of Common Stock Warrants															$ 9,200,000
Underwriter Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)						1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 1.375
Class of Warrant or Right, Exercised During Period (in shares)																	609,849
Class of Warrant or Right, Issued During Period (in shares)						636,364
Class of Warrant or Right, Period to Expiration (Year)						5 years
Class of Warrant or Right, Issued During Period, Fair Value						$ 333,000
Proceeds from Exercise of Common Stock Warrants																	$ 800,000
Warrants in Connection with the September 2019 Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)					30,666,667
Warrants and Rights Outstanding					$ 497,000
Warrants in Connection with the September 2019 Offering [Member] \| Over-Allotment Option [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)					4,000,000
Underwriter Warrants, September 2019 [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)					1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)					$ 0.375
Warrants and Rights Outstanding					$ 497,000
Class of Warrant or Right, Exercised During Period (in shares)																2,115,738
Class of Warrant or Right, Issued During Period (in shares)					2,115,738
Class of Warrant or Right, Period to Expiration (Year)					5 years
Proceeds from Exercise of Common Stock Warrants																$ 800,000
The March 2020 Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				2,000,000
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)				1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 2.50
Warrants and Rights Outstanding, Term (Year)				5 years
Warrants and Rights Outstanding				$ 453,000
Class of Warrant or Right, Exercised During Period (in shares)														1,970,850
Proceeds from Exercise of Common Stock Warrants														$ 4,900,000
The March 2020 Offering Placement Agent Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)				1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 3.125
Warrants and Rights Outstanding				$ 453,000
Class of Warrant or Right, Exercised During Period (in shares)														179,468
Class of Warrant or Right, Issued During Period (in shares)				280,000
Proceeds from Exercise of Common Stock Warrants														$ 600,000

Note 16 - Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current:
Federal	$ 0	$ 0	$ 0
State	1	3	2
Foreign	106	235	488
Total Current	107	238	490
Deferred:
Federal	0	0	0
State	0	0	0
Foreign	0	0	0
Total Deferred	0	0	0
Provision for income taxes	$ 107	$ 238	$ 490

Note 17 - Net Loss Per Share Attributable to Common Stockholders

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Text Block]

NOTE 17. Net Loss Per Share Attributable to Common Stockholders

The following table presents the calculation of basic and diluted net loss per share (in thousands, except share and per share amounts):

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

Net loss	$	(70,470	)	$	(32,220	)	$	(18,645	)

Shares used to compute net loss per share, basic and diluted		121,453,723			88,295,762			21,569,523

Net loss per share attributable to common stockholders, basic and diluted	$	(0.58	)	$	(0.36	)	$	(0.86	)

No adjustment has been made to the net loss attributable to common stockholders as the effect would be anti-dilutive due to the net loss.

The following potentially dilutive securities were excluded from the computation of diluted weighted average shares outstanding because they would have been antidilutive:

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Options to purchase common stock		8,206,137		4,409,806		1,583,575

Warrants to purchase common stock		369,043		14,773,425		17,579,945

Total potentially dilutive securities excluded from denominator of the diluted earnings per share computation		8,575,180		19,183,231		19,163,520

Note 17 - Net Loss Per Share Attributable to Common Stockholders (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

Net loss	$	(70,470	)	$	(32,220	)	$	(18,645	)

Shares used to compute net loss per share, basic and diluted		121,453,723			88,295,762			21,569,523

Net loss per share attributable to common stockholders, basic and diluted	$	(0.58	)	$	(0.36	)	$	(0.86	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Options to purchase common stock		8,206,137		4,409,806		1,583,575

Warrants to purchase common stock		369,043		14,773,425		17,579,945

Total potentially dilutive securities excluded from denominator of the diluted earnings per share computation		8,575,180		19,183,231		19,163,520

Note 12 - Equity Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2021

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

							*Weighted*
	*Shares*			*Number of*			*Average*
	*Available*			*Options*			*Exercise*
	*For Grant*			*Outstanding*			*Price*

Balance at January 1, 2019		200,650			865,163		$	8.13
Authorized under 2019 Plan on Adoption		1,600,000			—		$	—
Removed from 2016 Plan		(223,389	)		—		$	—
Granted		(1,791,030	)		1,791,030		$	0.67
Forfeited		483,849			(592,528	)	$	1.57
Canceled		25,100			(252,013	)	$	9.25

Balance at December 31, 2019		295,180			1,811,652		$	2.74

Authorized under 2019 Plan Amendment		6,400,000			—		$	—
Granted		(5,579,800	)		5,579,800		$	2.66
Exercised		—			(414,676	)	$	1.45
Forfeited		105,910			(105,992	)	$	1.65
Canceled		9,573			(57,751	)	$	10.57

Balance at December 31, 2020		1,230,863			6,813,033		$	2.70

Authorized under 2019 Plan Amendment		8,900,000			—		$	—
Granted		(5,178,438	)		5,178,438		$	7.09
Exercised		—			(1,070,921	)	$	1.63
Forfeited		630,317			(650,054	)	$	3.16
Canceled		—			(54,390	)	$	11.98

Balance at December 31, 2021		5,582,742			10,216,106		$	4.96

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

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

Risk-free interest rate		0.91% - 1.35%			0.40% - 0.88%			1.68% - 2.31%
Expected term (in years)		5.44 - 6.08			5.22 - 10.00			5.39 - 10.00
Expected volatility		122% - 131%			94% - 111%			83% - 85%
Dividend yield		—	%		—	%		—	%

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

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Research and development	$	4,304	$	1,563	$	253
General and administrative		4,563		2,795		374
Total stock-based compensation	$	8,867	$	4,358	$	627

Note 16 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Beginning Balance	$ 1,281	$ 851	$ 1,582
Additions based on tax positions related to the current year	1,132	431	159
Increase related to prior years’ tax positions	9
Decrease related to prior years’ tax positions		(1)	(890)
Ending Balance	$ 2,422	$ 1,281	$ 851

Note 3 - Business Combination

12 Months Ended

Dec. 31, 2021

Business Combination Disclosure [Text Block]

NOTE 3. Business Combination

On November 30, 2021, the Company closed its acquisition of Kindred BioSciences, Inc.’s GMP manufacturing line in Burlingame, California in exchange for $4.8 million in cash. The transaction was accounted for as a business combination and the Company incurred transaction related expenses totaling $82,000, which were recorded within general and administrative expenses in the consolidated statement of operations.

The fair value of the assets acquired in connection with the acquisition are as follows (in thousands):

Property and equipment	$	321
Goodwill		4,508

Total purchase price	$	4,829

In addition, the Company paid $671,000 in prepaid rent in connection with the modification of the pre-existing embedded lease at the Burlingame facility (see Note 8).

Goodwill, which represents the excess of the purchase price over the fair value of assets acquired, is attributable primarily to the expected cost savings of manufacturing internally, as opposed to outsourcing, and the assembled workforce. All of the goodwill is expected to be deductible for income tax purposes.

Note 5 - Balance Sheet Components (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss, Current, Total	$ 71,000	$ 334,000
Depreciation, Total	732,000	114,000	$ 504,000
Amortization of Intangible Assets, Total	1,700,000	1,700,000	2,300,000
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 3,005,000	0	0
Developed Technology Rights [Member]
Finite-Lived Intangible Asset, Remaining Life (Year)	7 years 10 months 24 days
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 3,000,000.0
Intellectual Property [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years
Finite-Lived Intangible Asset, Remaining Life (Year)	6 years
Minimum [Member] \| Developed Technology Rights [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	1 year 3 months 18 days
Maximum [Member] \| Developed Technology Rights [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	11 years 9 months
Restructuring Charges [Member]
Impairment of Right-of-use Asset			120,000
Restructuring Charges [Member] \| CALIFORNIA
Asset Impairment Charges, Total			$ 1,152,000
Royalty [Member]
Accounts Receivable, after Allowance for Credit Loss, Current, Total	$ 71,000	$ 334,000

Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member] The March 2020 Offering [Member] Underwriters' Designees [Member]	Common Stock [Member] The March 2020 Offering [Member]	Common Stock [Member] The September 2019 Offering [Member] Underwriters' Designees [Member]	Common Stock [Member] The September 2019 Offering [Member]	Common Stock [Member] The July 2020 Offering [Member]	Common Stock [Member] The April 2019 Offering [Member] Underwriters' Designees [Member]	Common Stock [Member] The April 2019 Offering [Member]	Common Stock [Member] The December 2020 Offering [Member]	Common Stock [Member] The October 2020 Offering [Member] Underwriters' Designees [Member]	Common Stock [Member] Placement Agents' Designees [Member]	Common Stock [Member]	Additional Paid-in Capital [Member] The March 2020 Offering [Member] Underwriters' Designees [Member]	Additional Paid-in Capital [Member] The March 2020 Offering [Member]	Additional Paid-in Capital [Member] The September 2019 Offering [Member] Underwriters' Designees [Member]	Additional Paid-in Capital [Member] The September 2019 Offering [Member]	Additional Paid-in Capital [Member] The July 2020 Offering [Member]	Additional Paid-in Capital [Member] The April 2019 Offering [Member] Underwriters' Designees [Member]	Additional Paid-in Capital [Member] The April 2019 Offering [Member]	Additional Paid-in Capital [Member] The December 2020 Offering [Member]	Additional Paid-in Capital [Member] The October 2020 Offering [Member] Underwriters' Designees [Member]	Additional Paid-in Capital [Member] Placement Agents' Designees [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member] The March 2020 Offering [Member] Underwriters' Designees [Member]	Retained Earnings [Member] The March 2020 Offering [Member]	Retained Earnings [Member] The September 2019 Offering [Member] Underwriters' Designees [Member]	Retained Earnings [Member] The September 2019 Offering [Member]	Retained Earnings [Member] The July 2020 Offering [Member]	Retained Earnings [Member] The April 2019 Offering [Member] Underwriters' Designees [Member]	Retained Earnings [Member] The April 2019 Offering [Member]	Retained Earnings [Member] The December 2020 Offering [Member]	Retained Earnings [Member] The October 2020 Offering [Member] Underwriters' Designees [Member]	Retained Earnings [Member] Placement Agents' Designees [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member] The March 2020 Offering [Member] Underwriters' Designees [Member]	AOCI Attributable to Parent [Member] The March 2020 Offering [Member]	AOCI Attributable to Parent [Member] The July 2020 Offering [Member]	AOCI Attributable to Parent [Member] The December 2020 Offering [Member]	AOCI Attributable to Parent [Member] The October 2020 Offering [Member] Underwriters' Designees [Member]	AOCI Attributable to Parent [Member]	The March 2020 Offering [Member] Underwriters' Designees [Member]	The March 2020 Offering [Member]	The September 2019 Offering [Member] Underwriters' Designees [Member]	The September 2019 Offering [Member]	The July 2020 Offering [Member]	The April 2019 Offering [Member] Underwriters' Designees [Member]	The April 2019 Offering [Member]	The December 2020 Offering [Member]	The October 2020 Offering [Member] Underwriters' Designees [Member]	The October 2020 Offering [Member]	Placement Agents' Designees [Member]	Total
Balances (in shares) at Dec. 31, 2018											7,141,189
Balances at Dec. 31, 2018											$ 1											$ 109,226											$ (98,016)																		$ 11,211
Issuance of common stock, net of offering costs (in shares)											1,200,000
Issuance of common stock, net of offering costs											$ 0											2,440											0																		2,440
Issuance of common stock warrants to placement agents’ designees			$ 0			$ 0				$ 0				$ 333			$ 497				$ 100				$ 0			$ 0				$ 0										$ 333			$ 497					$ 100
Issuance of common stock, pre-funded warrants and common stock warrants, net of offering costs (in shares)				925,455			26,124,828
Issuance of common stock, pre-funded warrants and common stock warrants, net of offering costs				$ 0			$ 3								$ 7,741			$ 7,239								$ 0			$ 0														$ 7,741			$ 7,242
Issuance of common stock upon exercise of pre-funded warrants (in shares)											12,265,455
Issuance of common stock upon exercise of pre-funded warrants											$ 1											1,225											0																		1,226
Issuance of common stock upon exercise of common stock warrants (in shares)											598,067
Issuance of common stock upon exercise of common stock warrants											$ 0											180											0																		180
Stock-based compensation											0											627											0																		627
Net loss											$ 0											0											(18,645)																		$ (18,645)
Issuance of common stock upon exercise of options (in shares)																																																			0
Balances (in shares) at Dec. 31, 2019											48,254,994
Balances at Dec. 31, 2019											$ 5											129,608											(116,661)						$ 0												$ 12,952
Issuance of common stock, net of offering costs (in shares)					12,503,806			692,651
Issuance of common stock, net of offering costs					$ 1			$ 0								$ 97,033			$ 4,900								$ 0			$ 0						$ 0	$ 0							$ 97,034			$ 4,900
Issuance of common stock warrants to placement agents’ designees	$ 0											$ 453											$ 0											$ 0						$ 453
Issuance of common stock, pre-funded warrants and common stock warrants, net of offering costs (in shares)		4,000,000
Issuance of common stock, pre-funded warrants and common stock warrants, net of offering costs		$ 0											$ 8,722											$ 0											$ 0						$ 8,722
Issuance of common stock upon exercise of common stock warrants (in shares)											44,404,966
Issuance of common stock upon exercise of common stock warrants											$ 5											25,946											0						0												25,951
Stock-based compensation											0											4,358											0						0												4,358
Net loss											$ 0											0											(32,220)						0												$ (32,220)
Issuance of common stock upon exercise of options (in shares)											414,676																																								414,676
Issuance of common stock upon exercise of options											$ 0											602											0						0												$ 602
Disgorgement of short-swing profits, net of costs											$ 0											652											0						0												652
Balances (in shares) at Dec. 31, 2020											110,271,093
Balances at Dec. 31, 2020											$ 11											272,274											(148,881)						0												123,404
Issuance of common stock, net of offering costs (in shares)									13,239,839																																								13,239,839
Issuance of common stock, net of offering costs									$ 2											$ 122,208											$ 0							$ 0										$ 122,210
Issuance of common stock upon exercise of pre-funded warrants (in shares)											1,070,921
Issuance of common stock upon exercise of pre-funded warrants											$ 0											1,745											0						0												1,745
Issuance of common stock upon exercise of common stock warrants (in shares)											1,012,540
Issuance of common stock upon exercise of common stock warrants											$ 0											1,849											0						0												1,849
Stock-based compensation											0											8,867											0						0												8,867
Net loss											0											0											(70,470)						0												$ (70,470)
Issuance of common stock upon exercise of options (in shares)																																																			1,070,921
Unrealized losses on available-for-sale investments											$ 0											0											0						(74)												$ (74)
Balances (in shares) at Dec. 31, 2021											125,594,393
Balances at Dec. 31, 2021											$ 13											$ 406,943											$ (219,351)						$ (74)												$ 187,531

Note 11 - Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Common Stock Reserved for Issuance [Table Text Block]

	*December 31, 2021*		*December 31, 2020*

Options issued and outstanding		10,216,106		6,813,033
Available for future grants of equity awards		5,582,742		1,230,863
Common stock warrants		232,434		1,244,974
Total		16,031,282		9,288,870

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

Securities into which warrants are convertible	Warrants outstanding		Exercise Price		Expiration Date

Common Stock		5,000	$	0.30	September 2024
Common Stock		44,148	$	1.10	April 2024
Common Stock		26,515	$	1.375	April 2024
Common Stock		29,150	$	2.50	March 2025
Common Stock		100,532	$	3.125	February 2025
Common Stock		16,175	$	3.125	March 2024
Common Stock		10,914	$	22.99	December 2026
Total		232,434

Fair Value of Warrants, Assumptions [Table Text Block]

Offering	March 2019			April 2019			September 2019			March 2020
Aggregate valuation on issuance date	$	100,000		$	333,000		$	497,000		$	453,000
Number of warrants issued		84,000			636,364			2,115,738			280,000
Exercise price	$	3.125		$	1.375		$	0.375		$	3.125
Closing stock price	$	2.08		$	0.89		$	0.36		$	2.34
Risk-free interest rate		2.34	%		2.31	%		1.55	%		0.88	%
Expected term (in years)		5.00			5.00			5.00			4.99
Expected volatility		80	%		83	%		83	%		98	%
Dividend yield		—	%		—	%		—	%		—	%

Note 7 - Liabilities Related to Sale of Future Royalties (Details Textual) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2016	Dec. 31, 2021
Re-valuation Gain Recognized		$ 3.8
HCRP [Member]
Proceeds from Sale of Future Royalties, Net	$ 20.0
Royalty Interest Due Each Year	$ 3.0
Royalty Interest, Percentage of Additional Royalties Due Each Year	15.00%
Royalty Interest, Additional Royalties Due Each Year	$ 1.0

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation – The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).

Consolidation, Policy [Policy Text Block]

Basis of Consolidation – The consolidated financial statements include the financial statements of Vaxart, Inc. and its subsidiaries. All significant transactions and balances between Vaxart, Inc. and its subsidiaries have been eliminated in consolidation.

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 disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Actual results and outcomes could differ from these estimates and assumptions.

Foreign Currency Transactions and Translations Policy [Policy Text Block]

Foreign Currencies – Foreign exchange gains and losses for assets and liabilities of the Company’s non-U.S. subsidiaries for which the functional currency is the U.S. dollar are recorded in foreign exchange gain or loss, net within other income and (expenses) in the Company’s consolidated statements of operations and comprehensive loss. The Company has no subsidiaries for which the local currency is the functional currency.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents – The Company considers all highly liquid debt investments with an original maturity of three months or less when purchased to be cash equivalents. Cash equivalents, which may consist of amounts invested in money market funds, corporate bonds and commercial paper, are stated at fair value.

Investment, Policy [Policy Text Block]

Investments – Excess cash balances may be invested in marketable debt securities. All investments that are readily convertible to known amounts of cash with stated maturities greater than three months when purchased are classified as investments.

The Company determines the appropriate classification of its investments in marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. Marketable debt securities are classified and accounted for as available-for-sale. After consideration of the Company’s objectives to preserve capital, as well as its liquidity requirements, it may sell these debt securities prior to their stated maturities. These securities are carried at fair value and unrealized gains and losses, net of taxes, are reported as a component of stockholders’ equity, except for unrealized losses determined to be other-than-temporary, which are recorded within other income (expense). Any realized gains or losses on the sale of marketable debt securities are determined on a specific identification method, and such gains and losses are recorded as a component of other income (expense). Available-for-sale investments are classified as either current or non-current assets based on each instrument’s underlying effective maturity date and whether the Company has the intent and ability to hold the investment for a period of greater than 12 months. Marketable securities with remaining maturities of 12 months or less are classified as current and are reported as short-term investments in the consolidated balance sheets. Marketable securities with remaining maturities of more than 12 months for which the Company has the intent and ability to hold the investment for more than 12 months are classified as non-current and are included in long-term investments in the consolidated balance sheets.

Securities are evaluated for impairment at the end of each reporting period. Impairment is evaluated considering numerous factors, including whether a decline in fair value below the amortized cost basis is due to credit-related factors or non-credit-related factors, the financial condition and near-term prospects of the issuer, and intent and ability to hold the investment to allow for an anticipated recovery in fair value. A credit-related impairment is recognized as an allowance on the balance sheet with a corresponding adjustment to earnings. Any impairment that is not credit-related is recognized in other comprehensive loss, net of applicable taxes.

Concentration Risk, Credit Risk, Policy [Policy Text Block]

Concentration of Credit Risk – Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash, cash equivalents and available-for-sale investments. The Company places its cash, cash equivalents and available-for-sale investments at financial institutions that management believes are of high credit quality. The Company is exposed to credit risk in the event of default by the financial institutions holding the cash and cash equivalents to the extent such amounts are in excess of the federally insured limits. The Company has not experienced any losses on its deposits since inception.

The primary focus of the Company’s investment strategy is to preserve capital and meet liquidity requirements. The Company’s investment policy addresses the level of credit exposure by limiting the concentration in any one corporate issuer or sector and establishing a minimum allowable credit rating.

Receivable [Policy Text Block]

Accounts Receivable – Accounts receivable arise from the Company’s royalty revenue receivable for sales, net of estimated returns, of Inavir and, until the patent expired in 2019, Relenza, and from its contracts with customers and with the Department of Health and Human Services, Office of Biomedical Advanced Research and Development Authority (“HHS BARDA”) (see Note 6) and are reported at amounts expected to be collected in future periods. An allowance for uncollectible accounts will be recorded based on a combination of historical experience, aging analysis and information on specific accounts, with related amounts recorded as a reserve against revenue recognized. Account balances will be written off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. The Company has provided no allowance for uncollectible accounts as of December 31, 2021 and 2020.

Property, Plant and Equipment, Policy [Policy Text Block]

Property and Equipment – Property and equipment is carried at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the respective assets. Depreciation begins at the time the asset is placed in service. Maintenance and repairs are charged to operations as incurred. Upon sale or retirement of assets, the cost and related accumulated depreciation are removed from the balance sheet and the resulting gain or loss is reflected in other income and (expenses) in the period realized.

The useful lives of the property and equipment are as follows:

Laboratory equipment (in years)			5
Office and computer equipment (in years)			3
Leasehold improvements			Shorter of remaining lease term or estimated useful life

Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block]

Goodwill and Other Intangible Assets – Goodwill, which represents the excess of the purchase price over the fair value of assets acquired, is not amortized. Intangible assets comprise developed technology and intellectual property. Intangible assets are carried at cost less accumulated amortization. Amortization is computed using the straight-line method over useful lives ranging from 1.3 to 11.75 years for developed technology and 20 years for intellectual property.

Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]

Impairment of Long-Lived Assets – The Company reviews its long-lived assets, including property and equipment, goodwill and intangible assets with finite lives, for impairment in the fourth quarter of each year, and more frequently whenever events or changes in circumstances indicate the carrying amount of these assets may not be recoverable. Recoverability of these assets is measured by comparison of the carrying amount of each asset to the future undiscounted cash flows the asset is expected to generate over its remaining life. When indications of impairment are present and the estimated undiscounted future cash flows from the use of these assets is less than the assets’ carrying value, the related assets will be written down to fair value. The Company assessed its manufacturing equipment and its right-of-use asset and leasehold improvements at its manufacturing premises as impaired in the year ended December 31, 2019 (see Note 14) and its developed technology as impaired in the year ended December 31, 2021 (see Note 5).

Accrued Clinical And Manufacturing Expenses Policy [Policy Text Block]

Accrued Clinical and Manufacturing Expenses – The Company accrues for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical studies and clinical trials, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided and includes the costs incurred but not yet invoiced within other accrued liabilities in the balance sheets and within research and development expense in the consolidated statements of operations and comprehensive loss. These costs can be a significant component of the Company’s research and development expenses.

The Company estimates the amount of services provided through discussions with internal personnel and external service providers as to the progress or stage of completion of the services and the agreed-upon fee to be paid for such services. The Company makes significant judgments and estimates in determining the accrued balance in each reporting period. As actual costs become known, it adjusts its accrued estimates. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of the status and timing of services performed, the number of subjects enrolled, and the rate of enrollment may vary from its estimates and could result in the Company reporting amounts that are too high or too low in any particular period. The Company’s accrued expenses are dependent, in part, upon the receipt of timely and accurate reporting from contract research organizations and other third-party service providers. To date, the Company has not experienced any material differences between accrued costs and actual costs incurred.

Lessee, Leases [Policy Text Block]

Leases – The Company records operating leases as right-of-use assets and operating lease liabilities in its consolidated balance sheets for all operating leases with terms exceeding one year. Right-of-use assets represent the right to use an underlying asset for the lease term, including extension options considered reasonably certain to be exercised, and operating lease liabilities to make lease payments. Right-of-use assets and operating lease liabilities are recognized based on the present value of lease payments over the lease term. To the extent that lease agreements do not provide an implicit rate, the Company uses its incremental borrowing rate based on information available at the lease commencement date to determine the present value of lease payments. The expense for operating lease payments is recognized on a straight-line basis over the lease term and is included in operating expenses in the Company’s consolidated statement of operations and comprehensive loss. The Company has elected to not separate lease and non-lease components of facilities leases, whereas non-lease components of equipment leases are accounted for separately from lease components.

Revenue [Policy Text Block]

Revenue Recognition – The Company recognizes revenue when it transfers control of promised goods or services to its customers, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. To determine revenue recognition, the Company performs the following five steps:

(i)

identification of the promised goods or services in the contract;

(ii)

determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract;

(iii)

measurement of the transaction price, including the constraint on variable consideration;

(iv)

allocation of the transaction price to the performance obligations based on estimated selling prices; and

(v)

recognition of revenue when (or as) the Company satisfies each performance obligation. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account.

Revenue from royalties earned as a percentage of sales, including milestone payments based on achieving a specified level of sales, where a license is deemed to be the predominant item to which the royalties relate, is recognized as revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied), as required under the sales- and usage-based royalty exception.

Revenue from contracts with customers is recognized ratably, based on costs incurred, as the Company provides promised services to its customers in amounts that reflect the consideration that the Company expects to receive for those services.

The Company performed research and development work under its cost-plus-fixed-fee contract with HHS BARDA. The Company recognizes revenue under research contracts only when a contract has been executed and the contract price is fixed or determinable. Revenue from the HHS BARDA contract is recognized in the period during which the related costs are incurred and the related services are rendered, provided that the applicable conditions under the contract have been met. Costs of contract revenue are recorded as a component of operating expenses in the consolidated statements of operations and comprehensive loss.

Under cost reimbursable contracts, the Company recognizes revenue as allowable costs are incurred and the fixed fee is earned. Reimbursable costs under the contract primarily include direct labor, subcontract costs, materials, equipment, travel, and approved overhead and indirect costs. Fixed fees under cost reimbursable contracts are earned in proportion to the allowable costs incurred in performance of the work relative to total estimated contract costs, with such costs incurred representing a reasonable measurement of the proportional performance of the work completed.

Payments to the Company under cost reimbursable contracts, such as this contract, are provisional payments subject to adjustment upon annual audit by the government. Management believes that revenue for periods not yet audited has been recorded in amounts that are expected to be realized upon final audit and settlement. When the final determination of the allowable costs for any year has been made, revenue and billings may be adjusted accordingly in the period that the adjustment is known.

Research and Development Expense, Policy [Policy Text Block]

Research and Development Costs – Research and development costs are expensed as incurred. Research and development costs consist primarily of salaries and benefits, stock-based compensation, consultant fees, third-party costs for conducting clinical trials and the manufacture of clinical trial materials, certain facility costs and other costs associated with clinical trials. Payments made to other entities are under agreements that are generally cancelable by the Company. Advance payments for research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related services are performed.

Share-based Payment Arrangement [Policy Text Block]

Stock-Based Compensation – The Company measures the fair value of all stock-based awards, including stock options, on the grant date and records the fair value of these awards, net of estimated forfeitures, to compensation expense over the service period. The fair value of options is estimated using the Black-Scholes valuation model. The expected term of each option is estimated by taking the arithmetic average of its original contractual term and its average vesting term.

Earnings Per Share, Policy [Policy Text Block]

Net Income (Loss) Per Share – Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period, without consideration of potential common shares.

Diluted net income (loss) per common share is computed giving effect to all potential dilutive common shares, comprising common stock issuable upon exercise of stock options and warrants. The Company uses the treasury-stock method to compute diluted income (loss) per share with respect to its stock options and warrants. For purposes of this calculation, options and warrants to purchase common stock are considered to be potential common shares and are only included in the calculation of diluted net income per share when their effect is dilutive. In the event of a net loss, the effects of all potentially dilutive shares are excluded from the diluted net loss per share calculation as their inclusion would be antidilutive.

Reclassification, Comparability Adjustment [Policy Text Block]

Reclassification

Prior year data is subject to reclassification to conform to current year presentation.

New Accounting Pronouncements, Policy [Policy Text Block]

Recently Adopted Accounting Pronouncements

In August 2020, the FASB issued Accounting Standards Update (ASU) 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in an Entity’s Own Equity (Subtopic 815-40). In addition to simplifying the accounting for certain debt and equity instruments, none of which the Company presently has outstanding, this standard update provides guidance on how certain instruments should be treated in the computation of earnings per share. The Company adopted the new guidance effective January 1, 2021. Its adoption had an immaterial impact on the number of shares used in the computation of year-to-date basic and diluted earnings per share.

Recent Accounting Pronouncements

The Company has reviewed all significant newly-issued accounting pronouncements that are not yet effective and concluded that they are either not applicable to its operations or their adoption will not have a material impact on its financial position or results of operations.

Note 16 - Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Text Block]

NOTE 16. Income Taxes

The provision for income taxes consists of the following (in thousands):

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Current:
Federal	$	—	$	—	$	—
State		1		3		2
Foreign		106		235		488

Total Current		107		238		490

Deferred:
Federal		—		—		—
State		—		—		—
Foreign		—		—		—

Total Deferred		—		—		—

Provision for income taxes	$	107	$	238	$	490

The components of the deferred tax assets are as follows (in thousands):

	*December 31, 2021*			*December 31, 2020*			*December 31, 2019*
Deferred tax assets:
Net operating loss carryforwards	$	30,256		$	14,161		$	6,924
Research and development tax credits		4,923			2,497			1,591
Capitalized research and development		4,016			4,534			4,773
Sale of future royalties		5,826			7,178			7,486
Lease liability		3,184			1,695			492
Accruals, reserves and other		3,043			1,327			1,253
Total deferred tax assets		51,248			31,392			22,519
Valuation allowance		(42,589	)		(21,952	)		(13,365	)
Deferred tax assets net of valuation allowance		8,659			9,440			9,154
Deferred tax liabilities:
Intangible assets		(5,410	)		(7,832	)		(8,730	)
Right-of-use assets		(3,223	)		(1,608	)		(424	)
Depreciation on property and equipment		(26	)		—			—
Total deferred tax liabilities		(8,659	)		(9,440	)		(9,154	)

Net deferred tax assets	$	—		$	—		$	—

A reconciliation of the provision for income taxes with the expected provision for income taxes computed by applying the federal statutory income tax rate of 21% to the net loss before provision for income taxes:

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

U.S. federal taxes at statutory rate		21.0	%		21.0	%		21.0	%
State taxes (net of federal benefit)		4.0			2.9			0.4
Foreign rate differential		0.3			(0.7	)		(2.6	)
Permanently non-deductible items		0.2			2.2			(3.7	)
Tax credits		3.4			2.8			1.7
Change in valuation allowance		(29.3	)		(26.8	)		194.2
Tax attributes write-off due to change in control		—			0.5			(208.3	)
Prior year true-up		0.6			(2.5	)		(0.9	)
Other		(0.3	)		(0.1	)		(4.5	)

Provision for income taxes		(0.1	)%		(0.7	)%		(2.7	)%

The Company’s actual tax expense differed from the statutory federal income tax expense using a tax rate of 21% for the year ended December 31, 2019, primarily due to the write-off of tax attributes due to a change in control. In addition, in each of the years ended December 31, 2021, 2020 and 2019, significant reasons for the difference between the actual tax rate and the federal rate of 21% were foreign income taxes being taxed at different rates, nondeductible expenses, research and development tax credits and the change in valuation allowance.

As of December 31, 2021, 2020 and 2019, the Company had net operating loss (“NOL”) carryforwards of $115.9 million, $51.6 million and $18.0 million for federal purposes, and $84.8 million, $26.8 million and $1.6 million for state purposes, respectively. If not utilized, these carryforwards will begin to expire in 2024 for federal, and 2028 for state purposes. The reductions in carryforwards in 2019 were primarily due to a change in ownership.

As of December 31, 2021, the Company also has accumulated tax losses of $6.7 million for Australia available for carry forward against future earnings, which under relevant tax laws do not expire but may not be available under certain circumstances.

As of December 31, 2021, 2020 and 2019, the Company had federal research and development tax credit carryforwards of $3.1 million, $0.9 million and $0.1 million, respectively and state research and development tax credit carryforwards of $5.0 million, $3.4 million and $2.7 million, respectively, before offset for unrecognized tax benefits, to offset future income tax liabilities. The federal research and development tax credits will expire at various dates beginning in 2039, if not utilized, while the state research and development tax credit can be carried forward indefinitely.

Sections 382 and 383 of the Internal Revenue Code provide for a limitation on the annual use of NOL and tax credit carryforwards following certain ownership changes that could limit the Company’s ability to utilize these carryforwards. The Company has completed an analysis to determine if such ownership changes have occurred and concluded it was more likely than not that there were changes in ownership. Due to the existence of full valuation allowance, limitations under Section 382 and 383 will not impact the Company’s effective tax rate. Further analyses will be performed prior to recognizing the benefits of any losses or credits in the consolidated financial statements.

The Company is required to reduce its deferred tax assets by a valuation allowance if it is more likely than not that some or all of its deferred tax assets will not be realized. Management must use judgment in assessing the potential need for a valuation allowance, which requires an evaluation of both negative and positive evidence. The weight given to the potential effect of negative and positive evidence should be commensurate with the extent to which it can be objectively verified. In determining the need for and amount of the valuation allowance, if any, the Company assesses the likelihood that it will be able to recover its deferred tax assets using historical levels of income, estimates of future income and tax planning strategies. As a result of historical cumulative losses, the Company determined that, based on all available evidence, there was substantial uncertainty as to whether it will recover recorded net deferred taxes in future periods. Accordingly, the Company recorded a valuation allowance against all its net deferred tax assets as of December 31, 2021, 2020 and 2019. The net change in total valuation allowance was an increase of approximately $20.6 million and $8.6 million for the years ended December 31, 2021 and 2020, respectively, a decrease of approximately $35.3 million for the year ended December 31, 2019. The decrease in 2019 is primarily due to the reduction in NOL and tax credit carryforwards that were triggered by the change in ownership on September 30, 2019.

The Company records unrecognized tax benefits, where appropriate, for all uncertain income tax positions. The Company recorded unrecognized tax benefits for uncertain tax positions of approximately $2.4 million and $1.3 million as of December 31, 2021 and 2020, respectively, none of which would impact the effective tax rate, if recognized, because the benefit would be offset by an increase in the valuation allowance.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):

	*Year Ended December 31,*
	*2021*		*2020*			*2019*

Beginning Balance	$	1,281	$	851		$	1,582
Additions based on tax positions related to the current year		1,132		431			159
Increase (decreases) related to prior years’ tax positions		9		(1	)		(890	)

Ending Balance	$	2,422	$	1,281		$	851

The Company’s policy is to recognize interest and penalties accrued on any unrecognized tax benefits as a component of income tax expense. During the years ended December 31, 2021, 2020 and 2019, the Company recognized no interest and penalties associated with unrecognized tax benefits. There are no tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly increase or decrease within twelve months of the reporting date.

The Company files income tax returns in the U.S. and Australia, as well as with various U.S. states. The Company is subject to tax audits in all jurisdictions in which it files income tax returns. Tax audits by their very nature are often complex and can require several years to complete. There are currently no tax audits that have commenced with respect to income tax returns in any jurisdiction.

Under the tax statute of limitations applicable to the Internal Revenue Code, the Company and its U.S. subsidiary, either standalone or as part of the consolidated group, is no longer subject to U.S. federal income tax examinations by the Internal Revenue Service for tax years before tax year 2018. Under the statute of limitations applicable to most state income tax laws, the Company is no longer subject to state income tax examinations by tax authorities for tax years before 2017 in states in which it has filed income tax returns. However, because the Company is carrying forward income tax attributes, such as net operating losses and tax credits, from earlier tax years, these attributes can still be audited when utilized on returns filed in the future. The Company is subject to foreign tax examinations by tax authorities for fiscal year 2016 and forward.

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 2
-Subparagraph (SAB Topic 11.C)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 235
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-Paragraph 1
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Note 19 - Subsequent Events (Details Textual) - USD ($) $ in Thousands		1 Months Ended	2 Months Ended	12 Months Ended
	Mar. 20, 2019	Sep. 30, 2021	Feb. 24, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock Issued During Period, Shares, New Issues (in shares)	1,200,000
Proceeds from Issuance of Common Stock	$ 2,500			$ 0	$ 9,175	$ 2,540
The September 2021 ATM [Member]
Stock Issued During Period, Shares, New Issues (in shares)		0
The September 2021 ATM [Member] \| Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)			216,000
Proceeds from Issuance of Common Stock			$ 1,000

Note 3 - Business Combination - Allocation of the Purchase Price to the Fair Value of the Respective Assets and Liabilities Acquired (Details) - USD ($) $ in Thousands	Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Business combination, goodwill acquired		$ 4,508	$ 0
Acquisition of Kindred BioSciences [Member]
Business combination, property and equipment acquired	$ 321
Business combination, goodwill acquired	4,508
Business Combination, Consideration Transferred, Total	$ 4,829

Note 16 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Current:
Federal	$	—	$	—	$	—
State		1		3		2
Foreign		106		235		488

Total Current		107		238		490

Deferred:
Federal		—		—		—
State		—		—		—
Foreign		—		—		—

Total Deferred		—		—		—

Provision for income taxes	$	107	$	238	$	490

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

	*December 31, 2021*			*December 31, 2020*			*December 31, 2019*
Deferred tax assets:
Net operating loss carryforwards	$	30,256		$	14,161		$	6,924
Research and development tax credits		4,923			2,497			1,591
Capitalized research and development		4,016			4,534			4,773
Sale of future royalties		5,826			7,178			7,486
Lease liability		3,184			1,695			492
Accruals, reserves and other		3,043			1,327			1,253
Total deferred tax assets		51,248			31,392			22,519
Valuation allowance		(42,589	)		(21,952	)		(13,365	)
Deferred tax assets net of valuation allowance		8,659			9,440			9,154
Deferred tax liabilities:
Intangible assets		(5,410	)		(7,832	)		(8,730	)
Right-of-use assets		(3,223	)		(1,608	)		(424	)
Depreciation on property and equipment		(26	)		—			—
Total deferred tax liabilities		(8,659	)		(9,440	)		(9,154	)

Net deferred tax assets	$	—		$	—		$	—

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

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

U.S. federal taxes at statutory rate		21.0	%		21.0	%		21.0	%
State taxes (net of federal benefit)		4.0			2.9			0.4
Foreign rate differential		0.3			(0.7	)		(2.6	)
Permanently non-deductible items		0.2			2.2			(3.7	)
Tax credits		3.4			2.8			1.7
Change in valuation allowance		(29.3	)		(26.8	)		194.2
Tax attributes write-off due to change in control		—			0.5			(208.3	)
Prior year true-up		0.6			(2.5	)		(0.9	)
Other		(0.3	)		(0.1	)		(4.5	)

Provision for income taxes		(0.1	)%		(0.7	)%		(2.7	)%

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

	*Year Ended December 31,*
	*2021*		*2020*			*2019*

Beginning Balance	$	1,281	$	851		$	1,582
Additions based on tax positions related to the current year		1,132		431			159
Increase (decreases) related to prior years’ tax positions		9		(1	)		(890	)

Ending Balance	$	2,422	$	1,281		$	851

Note 12 - Equity Incentive Plans

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Text Block]

NOTE 12. Equity Incentive Plans

On April 23, 2019, the Company’s stockholders approved the adoption of the 2019 Equity Incentive Plan (the “2019 Plan”), under which the Company is authorized to issue incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units, other stock awards and performance awards that may be settled in cash, stock, or other property. The 2019 Plan is designed to secure and retain the services of employees, directors and consultants, provide incentives for the Company’s employees, directors and consultants to exert maximum efforts for the success of the Company and its affiliates, and provide a means by which employees, directors and consultants may be given an opportunity to benefit from increases in the value of the Company’s common stock. Following adoption of the 2019 Plan, all previous plans were frozen, and on forfeiture, cancellation and expiration, awards under those plans are not assumed by the 2019 Plan.

The aggregate number of shares of common stock authorized for issuance under the 2019 Plan was initially 1,600,000 shares, which was increased through an amendment to the 2019 Plan adopted by the Company’s stockholders (a “Plan Amendment”) on June 8, 2020, to 8,000,000, and by a Plan Amendment on June 16, 2021, to 16,900,000, subject to standard adjustments in the event of a stock split, stock dividend or other extraordinary dividend, or other similar change in the Company’s common stock or capital structure. Further amendments to the 2019 Plan to increase the share reserve would require stockholder approval. Awards that expire or are canceled generally become available for issuance again under the 2019 Plan. Awards have a maximum term of ten years from the grant date and may vest over varying periods, as specified by the Company’s board of directors for each grant.

A summary of stock option transactions in each of the three years ended December 31, 2021, is as follows:

							*Weighted*
	*Shares*			*Number of*			*Average*
	*Available*			*Options*			*Exercise*
	*For Grant*			*Outstanding*			*Price*

Balance at January 1, 2019		200,650			865,163		$	8.13
Authorized under 2019 Plan on Adoption		1,600,000			—		$	—
Removed from 2016 Plan		(223,389	)		—		$	—
Granted		(1,791,030	)		1,791,030		$	0.67
Forfeited		483,849			(592,528	)	$	1.57
Canceled		25,100			(252,013	)	$	9.25

Balance at December 31, 2019		295,180			1,811,652		$	2.74

Authorized under 2019 Plan Amendment		6,400,000			—		$	—
Granted		(5,579,800	)		5,579,800		$	2.66
Exercised		—			(414,676	)	$	1.45
Forfeited		105,910			(105,992	)	$	1.65
Canceled		9,573			(57,751	)	$	10.57

Balance at December 31, 2020		1,230,863			6,813,033		$	2.70

Authorized under 2019 Plan Amendment		8,900,000			—		$	—
Granted		(5,178,438	)		5,178,438		$	7.09
Exercised		—			(1,070,921	)	$	1.63
Forfeited		630,317			(650,054	)	$	3.16
Canceled		—			(54,390	)	$	11.98

Balance at December 31, 2021		5,582,742			10,216,106		$	4.96

As of December 31, 2021, there were 10,216,106 options outstanding with a weighted average exercise price of $4.96, a weighted average remaining term of 8.67 years and an aggregate intrinsic value of $18.7 million. Of these options, 9,577,757 were expected to vest, with a weighted average exercise price of $4.85, a weighted average remaining term of 8.62 years and an aggregate intrinsic value of $18.4 million. Of these, 3,743,237 were vested, with a weighted average exercise price of $2.71, a weighted average remaining term of 7.62 years and an aggregate intrinsic value of $14.2 million.

The aggregate intrinsic value represents the total pre-tax value (i.e., the difference between the Company’s stock price and the exercise price) of stock options outstanding as of December 31, 2021, based on the Company’s common stock closing price of $6.27, which would have been received by the option holders had all their in-the-money options been exercised as of that date.

The Company received $1.7 million for the 1,070,921 options exercised during the year ended December 31, 2021, which had an intrinsic value of $6.2 million, and received $602,000 for the 414,676 options exercised during the year ended December 31, 2020, which had an intrinsic value of $2.2 million. There were no options exercised in the year ended December 31, 2019.

On June 15, 2020, the Company awarded 900,000 performance-based options with an exercise price of $2.46 per share to its new Chief Executive Officer. Vesting of these options would occur if the Company achieved a specified closing price during any ten consecutive trading days by November 30, 2020, with one-third based on a closing price of $5.00, one-third based on a closing price of $7.50 and one-third based on a closing price of $10.00, subject to continuing employment. Utilizing a Monte Carlo Simulation and assumptions of the fair value of Common Stock of $2.46, estimated volatility of 105%, a risk-free interest rate of 0.35%, a zero dividend rate and an expected term of 5.23 years, the Company determined the weighted average fair value of these options on the issuance date to be $0.31 per share, or $279,000, which was initially being expensed over the estimated vesting term, assuming vesting occurs by November 30, 2020, for each tranche. The tranches based on closing prices of $5.00, $7.50 and $10.00 vested on July 9, 2020, July 20, 2020 and July 24, 2020, respectively, so the unamortized balance as of June 30, 2020, was expensed in the three months ended September 30, 2020.

Excluding these performance-based options, the weighted average grant date fair value of options awarded in the years ended December 31, 2021, 2020 and 2019, was $6.49, $2.49 and $0.48, respectively. Fair values were estimated using the following assumptions:

	*Year Ended December 31,*
	*2021*			*2020*			*2019*

Risk-free interest rate		0.91% - 1.35%			0.40% - 0.88%			1.68% - 2.31%
Expected term (in years)		5.44 - 6.08			5.22 - 10.00			5.39 - 10.00
Expected volatility		122% - 131%			94% - 111%			83% - 85%
Dividend yield		—	%		—	%		—	%

The Company measures the fair value of all stock-based awards on the grant date and records the fair value of these awards, net of estimated forfeitures, to compensation expense over the service period. Total stock-based compensation recognized for options was as follows (in thousands):

	*Year Ended December 31,*
	*2021*		*2020*		*2019*

Research and development	$	4,304	$	1,563	$	253
General and administrative		4,563		2,795		374
Total stock-based compensation	$	8,867	$	4,358	$	627

Effective June 16, 2021, the Company modified the terms of outstanding options awarded to its former Chairman of the Board, Wouter W. Latour, such that the vesting of 100,000 options that would otherwise have been forfeited was accelerated. Further, the post-termination exercise period for all his vested and outstanding options as of the termination date was extended from three months to the earlier of the expiry of their ten-year term and June 16, 2023. The Company recorded a charge for the incremental increase in fair value of $1.3 million, which was included in stock-based compensation expense within general and administrative expenses in the three months ended June 30, 2021.

As of December 31, 2021, the unrecognized stock-based compensation cost related to outstanding stock options that are expected to vest was $28.6 million, which the Company expects to recognize over an estimated weighted average period of 3.07 years.

Note 8 - Leases - Operating Lease Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating lease cost	$ 2,513	$ 1,145	$ 959
Short-term lease cost	340	13	15
Variable lease cost	1,233	264	162
Sublease income	(36)	(217)	(217)
Total lease cost	$ 4,050	$ 1,205	$ 919

Note 18 - Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2021

Quarterly Financial Information [Text Block]

NOTE 18. Quarterly Financial Data (Unaudited)

Selected summarized quarterly financial information for each of the last three fiscal years is as follows (in thousands):

	*Year Ended December 31, 2021*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	506		$	112		$	200		$	74
Operating expenses	$	16,017		$	15,887		$	17,451		$	24,289
Net loss	$	(16,007	)	$	(16,116	)	$	(17,583	)	$	(20,764	)
Net loss per share – basic and diluted	$	(0.14	)	$	(0.13	)	$	(0.14	)	$	(0.17	)

	*Year Ended December 31, 2020*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	2,902		$	523		$	265		$	356
Operating expenses	$	3,596		$	9,049		$	7,854		$	13,717
Net loss	$	(1,297	)	$	(8,977	)	$	(8,085	)	$	(13,861	)
Net loss per share – basic and diluted	$	(0.02	)	$	(0.12	)	$	(0.08	)	$	(0.13	)

	*Year Ended December 31, 2019*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	5,407		$	85		$	454		$	3,916
Operating expenses	$	5,855		$	5,082		$	5,168		$	9,542
Net loss	$	(1,339	)	$	(5,637	)	$	(5,260	)	$	(6,409	)
Net loss per share – basic and diluted	$	(0.18	)	$	(0.39	)	$	(0.32	)	$	(0.13	)

Note 5 - Balance Sheet Components - Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accrued compensation	$ 2,786	$ 1,618
Accrued clinical and manufacturing expenses	986	1,772
Accrued professional and consulting services	556	777
Other liabilities, current portion	736	632
Total	$ 5,064	$ 4,799

Note 5 - Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2021

Cash, Cash Equivalents and Investments [Table Text Block]

	*Amortized*		*Gross Unrealized*					*Estimated*		*Cash and Cash*		*Short-Term*		*Long-Term*
	*Cost*		*Gains*		*Losses*			*Fair Value*		*Equivalents*		*Investments*		*Investments*
December 31, 2021
Cash at banks	$	72,767	$	—	$	—		$	72,767	$	72,767	$	—	$	—
Money market funds		70,978		—		—			70,978		70,978		—		—
U.S. Treasury securities		25,055		—		(58	)		24,997		—		12,022		12,975
Commercial paper		7,491		—		—			7,491		—		7,491		—
Corporate debt securities		6,480		—		(16	)		6,464		—		3,229		3,235
Total	$	182,771	$	—	$	(74	)	$	182,697	$	143,745	$	22,742	$	16,210

	Amortized		Gross Unrealized				Estimated		Cash and Cash		Short-Term		Long-Term
	Cost		Gains		Losses		Fair Value		Equivalents		Investments		Investments
December 31, 2020
Cash at banks	$	66,865	$	—	$	—	$	66,865	$	66,865	$	—	$	—
Money market funds		60,005		—		—		60,005		60,005		—		—
Total	$	126,870	$	—	$	—	$	126,870	$	126,870	$	—	$	—

Property, Plant and Equipment [Table Text Block]

	*December 31, 2021*			*December 31, 2020*

Laboratory equipment	$	5,057		$	1,759
Office and computer equipment		481			294
Leasehold improvements		1,063			—
Construction in progress		1,305			—
Total property and equipment		7,906			2,053
Less: accumulated depreciation		(1,305	)		(573	)
Property and equipment, net	$	6,601		$	1,480

Lessee, Operating Lease, Right-of-Use Assets [Table Text Block]

	*December 31, 2021*		*December 31, 2020*

Facilities	$	13,168	$	6,836
Office equipment		—		2
Right-of-use assets, net	$	13,168	$	6,838

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	*December 31, 2021*			*December 31, 2020*

Developed technology	$	10,600		$	20,300
Intellectual property		80			80
Total cost		10,680			20,380
Less: accumulated amortization		(56	)		(5,019	)
Intangible assets, net	$	10,624		$	15,361

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

Year Ending December 31,	Amount
2022	$	1,350
2023		1,350
2024		1,350
2025		1,350
2026		1,350
Thereafter		3,874
Total	$	10,624

Schedule of Accrued Liabilities [Table Text Block]

	*December 31, 2021*		*December 31, 2020*

Accrued compensation	$	2,786	$	1,618
Accrued clinical and manufacturing expenses		986		1,772
Accrued professional and consulting services		556		777
Other liabilities, current portion		736		632
Total	$	5,064	$	4,799

Note 5 - Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property and equipment, gross	$ 7,906	$ 2,053
Less: accumulated depreciation	(1,305)	(573)
Property and equipment, net	6,601	1,480
Laboratory Equipment [Member]
Property and equipment, gross	5,057	1,759
Office Equipment [Member]
Property and equipment, gross	481	294
Leasehold Improvements [Member]
Property and equipment, gross	1,063	0
Construction in Progress [Member]
Property and equipment, gross	$ 1,305	$ 0

Note 2 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Property, Plant, and Equipment, Useful Life [Table Text Block]

Laboratory equipment (in years)			5
Office and computer equipment (in years)			3
Leasehold improvements			Shorter of remaining lease term or estimated useful life

Note 5 - Balance Sheet Components

12 Months Ended

Dec. 31, 2021

Supplemental Balance Sheet Disclosures [Text Block]

NOTE 5. Balance Sheet Components

(a) Cash, Cash Equivalents and Investments

Cash, cash equivalents and investments consisted of the following (in thousands):

	*Amortized*		*Gross Unrealized*					*Estimated*		*Cash and Cash*		*Short-Term*		*Long-Term*
	*Cost*		*Gains*		*Losses*			*Fair Value*		*Equivalents*		*Investments*		*Investments*
December 31, 2021
Cash at banks	$	72,767	$	—	$	—		$	72,767	$	72,767	$	—	$	—
Money market funds		70,978		—		—			70,978		70,978		—		—
U.S. Treasury securities		25,055		—		(58	)		24,997		—		12,022		12,975
Commercial paper		7,491		—		—			7,491		—		7,491		—
Corporate debt securities		6,480		—		(16	)		6,464		—		3,229		3,235
Total	$	182,771	$	—	$	(74	)	$	182,697	$	143,745	$	22,742	$	16,210

	Amortized		Gross Unrealized				Estimated		Cash and Cash		Short-Term		Long-Term
	Cost		Gains		Losses		Fair Value		Equivalents		Investments		Investments
December 31, 2020
Cash at banks	$	66,865	$	—	$	—	$	66,865	$	66,865	$	—	$	—
Money market funds		60,005		—		—		60,005		60,005		—		—
Total	$	126,870	$	—	$	—	$	126,870	$	126,870	$	—	$	—

(b) Accounts Receivable

Accounts receivable comprises royalties receivable of $71,000 and $334,000 as of December 30, 2021 and 2020, respectively.

(c) Property and Equipment, Net

Property and equipment, net consists of the following (in thousands):

	*December 31, 2021*			*December 31, 2020*

Laboratory equipment	$	5,057		$	1,759
Office and computer equipment		481			294
Leasehold improvements		1,063			—
Construction in progress		1,305			—
Total property and equipment		7,906			2,053
Less: accumulated depreciation		(1,305	)		(573	)
Property and equipment, net	$	6,601		$	1,480

Depreciation expense was $732,000, $114,000 and $504,000 for the years ended December 31, 2021, 2020 and 2019, respectively. Property and equipment and leasehold improvements at one of the Company’s leased premises in California that were used in the Company’s manufacturing operations (see Note 14) were assessed as impaired as of December 31, 2019, and accordingly an impairment charge of $1,152,000 was recorded as a component of restructuring costs within operating expenses.

(d) Right-of-Use Assets, Net

Right-of-use assets consist of the following (in thousands):

	*December 31, 2021*		*December 31, 2020*

Facilities	$	13,168	$	6,836
Office equipment		—		2
Right-of-use assets, net	$	13,168	$	6,838

The right of use of one of the Company’s leased premises in California used in the Company’s manufacturing operations (see Note 14) was assessed as impaired as of December 31, 2019, and accordingly an impairment charge of $120,000 was recorded as a component of restructuring costs within operating expenses.

(e) Intangible Assets, Net

Intangible assets comprise developed technology, intellectual property and, until it was considered fully impaired, in-process research and development. Intangible assets are carried at cost less accumulated amortization. Amortization is computed using the straight-line method over useful lives ranging from 1.3 to 11.75 years for developed technology and 20 years for intellectual property. As of December 31, 2021, developed technology and intellectual property had remaining lives of 7.9 and 6.0 years, respectively. Intangible assets consist of the following (in thousands):

	*December 31, 2021*			*December 31, 2020*

Developed technology	$	10,600		$	20,300
Intellectual property		80			80
Total cost		10,680			20,380
Less: accumulated amortization		(56	)		(5,019	)
Intangible assets, net	$	10,624		$	15,361

Intangible asset amortization expense was $1.7 million, $1.7 million and $2.3 million for the years ended December 31, 2021, 2020 and 2019, respectively. Due to a decline in royalties earned since the outbreak of COVID-19 (see Note 7), developed technology was assessed as partially impaired as of December 31, 2021, and accordingly an impairment charge of $3.0 million was recorded within operating expenses.

As of December 31, 2021, the estimated future amortization expense by year is as follows (in thousands):

Year Ending December 31,	Amount
2022	$	1,350
2023		1,350
2024		1,350
2025		1,350
2026		1,350
Thereafter		3,874
Total	$	10,624

(f) Other Accrued Liabilities

Other accrued liabilities consist of the following (in thousands):

	*December 31, 2021*		*December 31, 2020*

Accrued compensation	$	2,786	$	1,618
Accrued clinical and manufacturing expenses		986		1,772
Accrued professional and consulting services		556		777
Other liabilities, current portion		736		632
Total	$	5,064	$	4,799

Note 6 - Revenue

12 Months Ended

Dec. 31, 2021

Revenue [Text Block]

NOTE 6. Revenue

Service Contracts with Customers

Contract Balances. No amounts related to service contracts with customers were receivable as of December 31, 2021 or 2020. Contract assets, representing unbilled receivables where revenue has been recognized in advance of customer billings, as of December 31, 2021 and 2020, were nil and $219,000, respectively, which were included in prepaid expenses and other current assets.

Remaining Performance Obligations. Remaining Performance Obligations (“RPO”) comprise deferred revenue plus unbilled contract revenue. As of December 31, 2021 and 2020, there was no deferred revenue and the aggregate amount of RPO was nil and $13,000, respectively, all of which was unbilled contract revenue which is not recorded on the balance sheet. Unbilled contract revenue represents non-cancelable contracts under which the Company has an obligation to perform, for which revenue has not yet been recognized in the financial statements and the fixed amounts billable have not yet been invoiced.

U.S. Government HHS BARDA Contract

In September 2015, HHS BARDA awarded the Company a contract to support the advanced development of a more effective and universal influenza vaccine to improve seasonal and pandemic influenza preparedness. On each of May 25 and July 18, 2017, and June 28, 2018, the Company entered into a Modification of Contract with HHS BARDA, the combined effect being to increase the value of the original $14 million contract by $1.7 million and to extend it through September 30, 2018. The modified contract is a cost-plus-fixed-fee contract, which reimburses the Company for allowable direct contract costs plus allowable indirect costs and a fixed-fee, totaling $15.7 million. As of December 31, 2021, the cumulative revenue recorded from inception under the HHS BARDA contract represents $20,000 less than the maximum amount billable under the contract as presently modified, with no further change orders envisaged.

Billings under the contract are based on approved provisional indirect billing rates, which permit recovery of fringe benefits, overhead and general and administrative expenses. Indirect rates as well as allowable costs are subject to audit by HHS BARDA on an annual basis. Management believes that revenues recognized to date have been recorded in amounts that are expected to be realized upon final audit and settlement. When the final determination of the allowable costs for any year has been made, revenue and billings may be adjusted accordingly in the period that the adjustments are known and collection is probable. Costs relating to contract acquisition are expensed as incurred. In the three months ended December 31, 2019, the Company reversed $20,000 in revenue that was invoiced late in 2018 to correct prior undercharges but which may never be received, and does not consider any of the revenue recorded as of December 31, 2021, to be at risk of reversal.

Royalty agreements

Aviragen entered into a royalty-bearing research and license agreement with GlaxoSmithKline, plc (“GSK”) in 1990 for the development and commercialization of zanamivir, a neuraminidase inhibitor marketed by GSK as Relenza,to treat influenza. All the Company’s Relenza patents have expired, the last remaining intellectual property related to the Relenza patent portfolio, which is solely owned by the Company and exclusively licensed to GSK, having expired in July 2019 in Japan, at which time royalty revenue ceased, although it remained subject to minor adjustments for sales returns and exchange rate differences. Royalty revenue related to Relenza in 2021, 2020 and 2019, was nil, $193,000 and $778,000, respectively.

The Company also generates royalty revenue from the sale of Inavir in Japan, pursuant to a collaboration and license agreement that Aviragen entered into with Daiichi Sankyo Company, Limited (“Daiichi Sankyo”), in 2009. In September 2010, laninamivir octanoate was approved for sale by the Japanese Ministry of Health and Welfare for the treatment of influenza in adults and children, which Daiichi Sankyo markets as Inavir. Under the agreement, the Company currently receives a 4% royalty on net sales of Inavir in Japan. The last patent related to Inavir is set to expire in December 2029 in Japan, at which time royalty revenue will cease. The royalty revenue related to Inavir recognized in 2021, 2020 and 2019, was nil, $2,769,000 and $3,668,000, respectively. In addition, the Company recognized non-cash royalty revenue related to sale of future royalties (see Note 7) of $879,000, $886,000 and $5,030,000 in 2021, 2020 and 2019, respectively. Both the royalty revenue and the non-cash royalty revenue related to sale of future royalties have been subjected to a 5% withholding tax in Japan, for which $44,000, $183,000 and $435,000 was included in income tax expense in the years ended December 31, 2021, 2020 and 2019, respectively.

Note 15 - Benefit Plan (Details Textual) - USD ($)	12 Months Ended
Note 15 - Benefit Plan (Details Textual) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	3.00%
Defined Contribution Plan, Cost	$ 288,000	$ 96,000	$ 140,000
Defined Contribution Plan, Administrative Expense	$ 14,000	$ 10,000	$ 14,000

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 143,745	$ 126,870
Short-term investments	22,742	0
Accounts receivable	71	334
Prepaid expenses and other current assets	2,609	1,327
Total current assets	169,167	128,531
Long-term investments	16,210	0
Property and equipment, net	6,601	1,480
Right-of-use assets, net	13,168	6,838
Intangible assets, net	10,624	15,361
Goodwill	4,508	0
Other long-term assets	890	372
Total assets	221,168	152,582
Current liabilities:
Accounts payable	3,872	2,133
Current portion of operating lease liability	1,011	2,052
Current portion of liability related to sale of future royalties	836	2,779
Other accrued current liabilities	5,064	4,799
Total current liabilities	10,783	11,763
Operating lease liability, net of current portion	11,997	5,156
Liability related to sale of future royalties, net of current portion	10,686	12,150
Other long-term liabilities	171	109
Total liabilities	33,637	29,178
Commitments and contingencies (Note 10)
Stockholders’ equity:
Preferred Stock: $0.0001 par value; 5,000,000 shares authorized; none issued and outstanding as of December 31, 2021 or 2020	0	0
Common Stock: $0.0001 par value; 150,000,000 shares authorized; 125,594,393 and 110,271,093 shares issued and outstanding as of December 31, 2021 and 2020, respectively	13	11
Additional paid-in capital	406,943	272,274
Accumulated deficit	(219,351)	(148,881)
Accumulated other comprehensive loss	(74)	0
Total stockholders’ equity	187,531	123,404
Total liabilities and stockholders’ equity	$ 221,168	$ 152,582

Note 16 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 20,600	$ 8,600	$ (35,300)
Unrecognized Tax Benefits, Ending Balance	2,422	1,281	851	$ 1,582
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	0	0	0
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	115,900	51,600	18,000
Domestic Tax Authority [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	3,100	900	100
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 84,800	26,800	1,600
Open Tax Year	2016 2017 2018 2019 2020 2021
State and Local Jurisdiction [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	$ 5,000	$ 3,400	$ 2,700
Foreign Tax Authority [Member] \| Australian Taxation Office [Member]
Operating Loss Carryforwards, Total	$ 6,700

Note 5 - Balance Sheet Components - Estimated Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2021 USD ($)
2022	$ 1,350
2023	1,350
2024	1,350
2025	1,350
2026	1,350
Thereafter	3,874
Total	$ 10,624

Note 6 - Revenue (Details Textual) - USD ($)		3 Months Ended												12 Months Ended
Note 6 - Revenue (Details Textual) - USD ($)	Jun. 28, 2018	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2015
Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total		$ 0				$ 0								$ 0	$ 0
Contract With Customer, Asset, Revenue Recognized		0				219,000								0	219,000
Contract with Customer, Liability, Total		0				0								0	0
Revenue, Remaining Performance Obligation, Amount		0				13,000								0	13,000
Revenue from Contract with Customer, Including Assessed Tax		$ 74,000	$ 200,000	$ 112,000	$ 506,000	$ 356,000	$ 265,000	$ 523,000	$ 2,902,000	$ 3,916,000	$ 454,000	$ 85,000	$ 5,407,000	892,000	4,046,000	$ 9,862,000
Income Tax Expense (Benefit), Total														$ 107,000	238,000	490,000
Foreign Tax Authority [Member] \| National Tax Agency, Japan [Member]
Royalty Withholding Tax														5.00%
Income Tax Expense (Benefit), Total														$ 44,000	183,000	435,000
Government Contract [Member]
Contract Value	$ 15,700,000																$ 14,000,000
Contract Value, Adjustment	$ 1,700,000
Contract with Customer, Asset, Credit Loss Expense (Reversal)														20,000
Contract with Customer, Asset, Allowance for Credit Loss, Writeoff																20,000
Revenue from Contract with Customer, Including Assessed Tax														0	0	(20,000)
Royalty [Member]
Revenue from Contract with Customer, Including Assessed Tax														0	2,962,000	4,446,000
Royalty [Member] \| GSK Research and License Agreement [Member]
Revenue from Contract with Customer, Including Assessed Tax														0	193,000	778,000
Royalty [Member] \| Daiichi Sankyo Collaberation and License Agreement [Member]
Revenue from Contract with Customer, Including Assessed Tax														$ 0	2,769,000	3,668,000
Royalty Percentage														4.00%
Non Cash Royalty Revenue [Member]
Revenue from Contract with Customer, Including Assessed Tax														$ 879,000	886,000	5,030,000
Non Cash Royalty Revenue [Member] \| Daiichi Sankyo Collaberation and License Agreement [Member]
Revenue from Contract with Customer, Including Assessed Tax														$ 879,000	$ 886,000	$ 5,030,000

Note 9 - Secured Promissory Note Payable to Oxford Finance (Details Textual) - USD ($)			12 Months Ended
	Nov. 04, 2019	Dec. 22, 2016	Dec. 31, 2019	Feb. 13, 2018
Amortization of Debt Issuance Costs	$ 98,000
Legal Fees	$ 2,000
Warrants in Connection with Loan Agreement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		7,563		10,914
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 33.11		$ 22.99
Warrants Not Settleable in Cash, Fair Value Disclosure		$ 134,000
Loan Agreement [Member] \| Oxford Finance [Member]
Long-term Debt, Gross		$ 5,000,000.0
Debt Instrument, Term (Year)		4 years
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid		$ 325,000
Debt Instrument, Interest Rate, Effective Percentage				10.50%
Interest Expense, Debt, Total			$ 311,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total			$ 223,000
Loan Agreement [Member] \| Oxford Finance [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		6.17%

Note 11 - Stockholders' Equity - Summary of Warrants Outstanding (Details)	Dec. 31, 2021 $ / shares shares
Warrants outstanding (in shares)	232,434
First Set of Warrants Expiring September 2024 [Member]
Warrants outstanding (in shares)	5,000
Exercise Price (in dollars per share) \| $ / shares	$ 0.30
First Set of Warrants Expiring April 2024 [Member]
Warrants outstanding (in shares)	44,148
Exercise Price (in dollars per share) \| $ / shares	$ 1.10
Second Set of Warrants Expiring April 2024 [Member]
Warrants outstanding (in shares)	26,515
Exercise Price (in dollars per share) \| $ / shares	$ 1.375
Warrants Expiring March 2025 [Member]
Warrants outstanding (in shares)	29,150
Exercise Price (in dollars per share) \| $ / shares	$ 2.50
Warrants Expiring February 2025 [Member]
Warrants outstanding (in shares)	100,532
Exercise Price (in dollars per share) \| $ / shares	$ 3.125
Warrants Expiring March 2024 [Member]
Warrants outstanding (in shares)	16,175
Exercise Price (in dollars per share) \| $ / shares	$ 3.125
Warrants Expiring December 2026 [Member]
Warrants outstanding (in shares)	10,914
Exercise Price (in dollars per share) \| $ / shares	$ 22.99

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	125,594,393	110,271,093
Common stock, shares outstanding (in shares)	125,594,393	110,271,093

Note 14 - Restructuring Charges (Reversals) (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Payments for Restructuring			$ 2,799,000	$ 1,272,000
Restructuring Charges (Reversals)		$ 0	(849,000)	4,920,000
Restructuring Reserve, Ending Balance		$ 0	0	3,648,000	$ 0
Contract Termination [Member]
Payments for Restructuring	$ 2,252,000		2,252,000	(0)
Restructuring Reserve, Ending Balance			$ 0	$ 3,223,000	$ 0

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	$ 892	$ 4,046	$ 9,862
Revenue	892	4,046	9,862
Operating expenses:
Research and development	48,749	19,863	14,540
General and administrative	21,890	15,202	6,187
Impairment of intangible assets	3,005	0	0
Restructuring charges (reversals)	0	(849)	4,920
Total operating expenses	73,644	34,216	25,647
Operating loss	(72,752)	(30,170)	(15,785)
Other income (expense):
Interest income	81	75	149
Interest expense	0	0	(315)
Non-cash interest expense related to sale of future royalties	(1,480)	(1,874)	(2,073)
Gain on sale of equipment	0	0	1
Gain on remeasurement of future royalty liability	3,789	0	0
Loss on debt extinguishment	0	0	(100)
Foreign exchange loss, net	(1)	(13)	(32)
Loss before income taxes	(70,363)	(31,982)	(18,155)
Provision for income taxes	107	238	490
Net loss	$ (70,470)	$ (32,220)	$ (18,645)
Net loss per share – basic and diluted (in dollars per share)	$ (0.58)	$ (0.36)	$ (0.86)
Shares used to compute net loss per share – basic and diluted (in shares)	121,453,723	88,295,762	21,569,523
Comprehensive loss:
Net loss	$ (70,470)	$ (32,220)	$ (18,645)
Unrealized loss on available-for-sale investments, net of tax	(74)	0	0
Comprehensive loss	(70,544)	(32,220)	(18,645)
Customer Service Contracts [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	13	198	406
Revenue	13	198	406
Government Contract [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	0	0	(20)
Revenue	0	0	(20)
Royalty [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	0	2,962	4,446
Revenue	0	2,962	4,446
Non Cash Royalty Revenue [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	879	886	5,030
Revenue	$ 879	$ 886	$ 5,030

Note 11 - Stockholders' Equity

12 Months Ended

Dec. 31, 2021

Stockholders' Equity Note Disclosure [Text Block]

NOTE 11. Stockholders’ Equity

(a) Convertible Preferred Stock

The Company is authorized to issue 5,000,000 shares of preferred stock, $0.0001 par value per share. The Company’s board of directors may, without further action by the stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of 5,000,000 shares of preferred stock in one or more series and authorize their issuance. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of our common stock. The issuance of preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deterring or preventing a change of control or other corporate action. No shares of preferred stock are currently outstanding, and the Company has no present plan to issue any shares of preferred stock.

(b) Common Stock

Except as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, the holders of common stock possess all voting power for the election of the Company’s directors and all other matters requiring stockholder action. Holders of common stock are entitled to one vote per share on matters to be voted on by stockholders. Holders of common stock are entitled to receive such dividends, if any, as may be declared from time to time by the Company’s board of directors in its discretion out of funds legally available therefor. In no event will any stock dividends or stock splits or combinations of stock be declared or made on common stock unless the shares of common stock at the time outstanding are treated equally and identically. As of December 31, 2021, no dividends had been declared by the board of directors.

In the event of the Company’s voluntary or involuntary liquidation, dissolution, distribution of assets or winding-up, the holders of the common stock will be entitled to receive an equal amount per share of all the Company’s assets of whatever kind available for distribution to stockholders, after the rights of the holders of the preferred stock have been satisfied. There are no sinking fund provisions applicable to the common stock.

The Company had shares of common stock reserved for issuance as follows:

	*December 31, 2021*		*December 31, 2020*

Options issued and outstanding		10,216,106		6,813,033
Available for future grants of equity awards		5,582,742		1,230,863
Common stock warrants		232,434		1,244,974
Total		16,031,282		9,288,870

(c) Warrants

The Company has the following warrants outstanding as of December 31, 2021, all of which contain standard anti-dilution protections in the event of subsequent rights offerings, stock splits, stock dividends or other extraordinary dividends, or other similar changes in the Company’s common stock or capital structure, and none of which have any participating rights for any losses:

Securities into which warrants are convertible	Warrants outstanding		Exercise Price		Expiration Date

Common Stock		5,000	$	0.30	September 2024
Common Stock		44,148	$	1.10	April 2024
Common Stock		26,515	$	1.375	April 2024
Common Stock		29,150	$	2.50	March 2025
Common Stock		100,532	$	3.125	February 2025
Common Stock		16,175	$	3.125	March 2024
Common Stock		10,914	$	22.99	December 2026
Total		232,434

The aggregate fair value at issuance of the warrants issued to the placement agents’ designees at the closing of the March 2019 Offering and the March 2020 Offering and to the underwriters’ designees at the closing of the April 2019 Offering and the September 2019 Offering (see Note 1) were estimated to be $100,000, $453,000, $333,000 and $497,000, respectively, using the Black-Scholes valuation model and using parameters and assumptions tabulated as follows:

Offering	March 2019			April 2019			September 2019			March 2020
Aggregate valuation on issuance date	$	100,000		$	333,000		$	497,000		$	453,000
Number of warrants issued		84,000			636,364			2,115,738			280,000
Exercise price	$	3.125		$	1.375		$	0.375		$	3.125
Closing stock price	$	2.08		$	0.89		$	0.36		$	2.34
Risk-free interest rate		2.34	%		2.31	%		1.55	%		0.88	%
Expected term (in years)		5.00			5.00			5.00			4.99
Expected volatility		80	%		83	%		83	%		98	%
Dividend yield		—	%		—	%		—	%		—	%

In the event of a Fundamental Transaction (a transfer of ownership of the Company as defined in the warrant) within the Company’s control, the holders of the unexercised common stock warrants exercisable for $0.30, $1.10 and $2.50 and those exercisable for $3.125 expiring in February 2025 shall be entitled to receive cash consideration equal to a Black-Scholes valuation, as defined in the warrant. If such Fundamental Transaction is not within the Company’s control, the warrantholders would only be entitled to receive the same form of consideration (and in the same proportion) as the holders of the Company’s common stock, hence these warrants are classified as a component of permanent equity.

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.

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Note 2 - Summary of Significant Accounting Policies - Estimated Useful Lives (Details)	12 Months Ended
	Dec. 31, 2021
Laboratory Equipment [Member]
Laboratory equipment (in years) (Year)	5 years
Office Equipment [Member]
Laboratory equipment (in years) (Year)	3 years
Leasehold Improvements [Member]
Leasehold improvements	Shorter of remaining lease term or estimated useful life

Note 13 - Related Party Transactions

12 Months Ended

Dec. 31, 2021

NOTE 13. Related Party Transactions

In April 2020, the Company recorded a net amount of $652,000 related to the disgorgement of stockholder short-swing profits under Section 16(b) of the Securities Exchange Act of 1934, as amended. The Company recognized these related party proceeds as an increase to contributed capital on the consolidated balance sheet.

Note 8 - Leases (Tables)

12 Months Ended

Dec. 31, 2021

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

Year Ending December 31,	Amount
2022	$	2,071
2023		2,123
2024		2,195
2025		2,297
2026		2,852
Thereafter		6,770
Undiscounted total		18,308
Less: imputed interest		(5,300	)
Present value of future minimum payments		13,008
Current portion of operating lease liability		(1,011	)
Operating lease liability, net of current portion	$	11,997

Lease, Cost [Table Text Block]

	*Year Ended December 31,*
	*2021*			*2020*			*2019*
Lease cost
Operating lease cost	$	2,513		$	1,145		$	959
Short-term lease cost		340			13			15
Variable lease cost		1,233			264			162
Sublease income		(36	)		(217	)		(217	)
Total lease cost	$	4,050		$	1,205		$	919

Note 18 - Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2021

Quarterly Financial Information [Table Text Block]

	*Year Ended December 31, 2021*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	506		$	112		$	200		$	74
Operating expenses	$	16,017		$	15,887		$	17,451		$	24,289
Net loss	$	(16,007	)	$	(16,116	)	$	(17,583	)	$	(20,764	)
Net loss per share – basic and diluted	$	(0.14	)	$	(0.13	)	$	(0.14	)	$	(0.17	)

	*Year Ended December 31, 2020*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	2,902		$	523		$	265		$	356
Operating expenses	$	3,596		$	9,049		$	7,854		$	13,717
Net loss	$	(1,297	)	$	(8,977	)	$	(8,085	)	$	(13,861	)
Net loss per share – basic and diluted	$	(0.02	)	$	(0.12	)	$	(0.08	)	$	(0.13	)

	*Year Ended December 31, 2019*
	*First*			*Second*			*Third*			*Fourth*

Revenue	$	5,407		$	85		$	454		$	3,916
Operating expenses	$	5,855		$	5,082		$	5,168		$	9,542
Net loss	$	(1,339	)	$	(5,637	)	$	(5,260	)	$	(6,409	)
Net loss per share – basic and diluted	$	(0.18	)	$	(0.39	)	$	(0.32	)	$	(0.13	)

Note 13 - Related Party Transactions (Details Textual)	1 Months Ended
Note 13 - Related Party Transactions (Details Textual)	Apr. 30, 2020 USD ($)
Disgorgement of Stockholder Short-swing Profits [Member]
Related Party Transaction, Amounts of Transaction	$ 652,000

Note 16 - Income Taxes - Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net operating loss carryforwards	$ 30,256	$ 14,161	$ 6,924
Research and development tax credits	4,923	2,497	1,591
Capitalized research and development	4,016	4,534	4,773
Sale of future royalties	5,826	7,178	7,486
Lease liability	3,184	1,695	492
Accruals, reserves and other	3,043	1,327	1,253
Total deferred tax assets	51,248	31,392	22,519
Valuation allowance	(42,589)	(21,952)	(13,365)
Deferred tax assets net of valuation allowance	8,659	9,440	9,154
Intangible assets	(5,410)	(7,832)	(8,730)
Right-of-use assets	(3,223)	(1,608)	(424)
Depreciation on property and equipment	(26)	0	0
Total deferred tax liabilities	(8,659)	(9,440)	(9,154)
Net deferred tax assets	$ 0	$ 0	$ 0

Note 3 - Business Combination (Details Textual)	Nov. 30, 2021 USD ($)
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed	$ 82,000
Prepaid Rent	671,000
Acquisition of Kindred BioSciences [Member]
Business Combination, Consideration Transferred, Total	$ 4,829,000

Note 14 - Restructuring Charges (Reversals) - Restructuring Liabilities (Details) - USD ($)	1 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021
Cumulative cost incurred				$ 4,071,000
Balance		$ 3,648,000	$ 0
Period charges		122,000	4,920,000
Settlements		(2,799,000)	(1,272,000)
Period reversals		(971,000)
Balance		0	3,648,000
Contract Termination [Member]
Cumulative cost incurred				2,252,000
Balance		3,223,000	0
Period charges		0	3,223,000
Settlements	$ (2,252,000)	(2,252,000)	0
Period reversals		(971,000)
Balance		0	3,223,000
Employee Severance [Member]
Cumulative cost incurred				368,000
Balance		368,000	0
Period charges		0	368,000
Settlements		(368,000)	0
Period reversals		0
Balance		0	368,000
Impairment Charges [Member]
Cumulative cost incurred				1,272,000
Balance		0	0
Period charges		0	1,272,000
Settlements		0	(1,272,000)
Period reversals		0
Balance		0	0
Other Restructuring [Member]
Cumulative cost incurred				$ 179,000
Balance		57,000	0
Period charges		122,000	57,000
Settlements		(179,000)	0
Period reversals		0
Balance		$ 0	$ 57,000

Note 5 - Balance Sheet Components - Cash and Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash and cash equivalents	$ 143,745	$ 126,870	$ 13,526	$ 11,506
Gross Unrealized Loss	(74)	0
Short-term investments	22,742	0
Long-term investments	16,210	0
Investments and Cash	182,771	126,870
Investments and Cash, Fair Value Disclosure	182,697	126,870
US Treasury Securities [Member]
Amortized Cost	25,055
Gross Unrealized Loss	(58)
Estimated Fair Value	24,997
Short-term investments	12,022
Long-term investments	12,975
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	7,491
Estimated Fair Value	7,491
Short-term investments	7,491
Corporate Debt Securities [Member]
Amortized Cost	6,480
Gross Unrealized Loss	(16)
Estimated Fair Value	6,464
Short-term investments	3,229
Long-term investments	3,235
Cash [Member]
Cash and Cash Equivalents, at Carrying Value	72,767	66,865
Money market funds, Fair Value	72,767	66,865
Cash and cash equivalents	72,767	66,865
Money Market Funds [Member]
Cash and Cash Equivalents, at Carrying Value	70,978	60,005
Money market funds, Fair Value	70,978	60,005
Cash and cash equivalents	$ 70,978	$ 60,005

Note 14 - Restructuring Charges (Reversals)

12 Months Ended

Dec. 31, 2021

Restructuring and Related Activities Disclosure [Text Block]

NOTE 14. Restructuring Charges (Reversals)

Restructuring liabilities primarily consisted of the estimated future obligations for contract suspension costs and severance and benefits obligations. These restructuring liabilities, all of which were paid in the year ending December 31, 2020, were recorded in either accounts payable or other accrued liabilities in the consolidated balance sheets.

The Company approved a reduction-in-force during the year ended December 31, 2019, for which it accrued severance and benefits charges, all of which were paid in the three months ended March 31, 2020. The Company also accrued the maximum amount potentially payable under a manufacturing work order which it suspended. Following negotiations with the vendor, the Company paid $2,252,000 in September 2020 in full settlement and reversed the remainder of the balance accrued. Further, the Company recorded impairment charges against property and equipment and right-of-use assets formerly used for manufacturing covering the period in which no benefits were expected to be derived, and incurred legal fees and accretion costs in connection with the restructuring. In the year ended December 31, 2020, the Company recorded costs for legal fees and for accretion related to the manufacturing premises. The Company recorded no charges or reversals in the year ended December 31, 2021, and does not expect to incur any further charges related to this restructuring.

Cumulative restructuring costs incurred and a reconciliation of the change in related liabilities during the years ended December 31, 2019 and 2020, is as follows (in thousands):

	*Suspension*			*Severance*			*Impairment*
	*of Contract*			*Benefits*			*Charges*			*Other*			*Total*

Cumulative cost incurred as of December 31, 2021	$	2,252		$	368		$	1,272		$	179		$	4,071

Reconciliation of liabilities:
Balance at January 1, 2019	$	—		$	—		$	—		$	—		$	—
Period charges		3,223			368			1,272			57			4,920
Settlements		—			—			(1,272	)		—			(1,272	)
Balance at December 31, 2019		3,223			368			—			57			3,648

Period charges		—			—			—			122			122
Period reversals		(971	)		—			—			—			(971	)
Settlements		(2,252	)		(368	)		—			(179	)		(2,799	)
Balance at December 31, 2020	$	—		$	—		$	—		$	—		$	—

There was no restructuring liability as of December 31, 2021.

Note 7 - Liabilities Related to Sale of Future Royalties - Deferred Revenue Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revaluation gain recognized	$ (3,800)
Current portion	(836)	$ (2,779)
Long-term portion	10,686	$ 12,150
HealthCare Royalty Partners III, L.P. [Member] \| Royalty Arrangement [Member]
Total liability related to sale of future royalties, start of year	14,929
Non-cash royalty revenue paid to HCRP	(1,098)
Non-cash interest expense recognized	1,480
Revaluation gain recognized	(3,789)
Total liability related to sale of future royalties, end of year	11,522
Current portion	(836)
Long-term portion	$ 10,686

Note 15 - Benefit Plan

12 Months Ended

Dec. 31, 2021

Retirement Benefits [Text Block]

NOTE 15. Benefit Plan

The Company provides a tax-qualified employee savings and retirement plan commonly known as a 401(k) plan (the “Plan”), which covers the Company’s eligible employees. Pursuant to the Plan, employees may elect to defer their current compensation up to the IRS annual contribution limit of $19,500 for calendar years 2021 and 2020, up from $19,000 for 2019. Employees age 50 or over may elect to contribute an additional $6,500 annually for 2021 and 2020, up from $6,000 for 2019.

Employees direct their contributions, which vest immediately, across a series of mutual funds. In the years ended December 31, 2021, 2020 and 2019, the Company matched employee contributions up to 3% of each employee’s eligible earnings, vesting immediately. The Company’s matching contributions totaled $288,000, $96,000 and $140,000 in the years ended December 31, 2021, 2020 and 2019, respectively. The costs of administering the Plan totaled $14,000, $10,000 and $14,000 in the years ended December 31, 2021, 2020 and 2019, respectively.

The entire disclosure for retirement benefits.

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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Note 4 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Recurring [Member]
Financial Liabilities Fair Value Disclosure, Total	$ 0	$ 0	$ 0

Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 0	$ 0
Developed Technology Rights [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	1 year 3 months 18 days
Developed Technology Rights [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	11 years 9 months
Intellectual Property [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years

Note 4 - Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	*Level 1*		*Level 2*		*Level 3*		*Total*
December 31, 2021
Recurring financial assets:
Money market funds	$	70,978	$	—	$	—	$	70,978
U.S. Treasury securities		—		24,997		—		24,997
Commercial paper		—		7,491		—		7,491
Corporate debt securities		—		6,464		—		6,464

Total assets	$	70,978	$	38,952	$	—	$	109,930

	Level 1		Level 2		Level 3		Total
December 31, 2020
Recurring financial assets:
Money market funds	$	60,005	$	—	$	—	$	60,005

Total assets	$	60,005	$	—	$	—	$	60,005

Note 10 - Commitments and Contingencies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)
Purchase Obligation, Total	$ 11.0
Long-term Purchase Commitment, Period (Month)	18 months
Lessee, Operating Lease, Lease Not yet Commenced	$ 14.9

Note 14 - Restructuring Charges (Reversals) (Tables)

12 Months Ended

Dec. 31, 2021

Schedule of Restructuring Reserve by Type of Cost [Table Text Block]

	*Suspension*			*Severance*			*Impairment*
	*of Contract*			*Benefits*			*Charges*			*Other*			*Total*

Cumulative cost incurred as of December 31, 2021	$	2,252		$	368		$	1,272		$	179		$	4,071

Reconciliation of liabilities:
Balance at January 1, 2019	$	—		$	—		$	—		$	—		$	—
Period charges		3,223			368			1,272			57			4,920
Settlements		—			—			(1,272	)		—			(1,272	)
Balance at December 31, 2019		3,223			368			—			57			3,648

Period charges		—			—			—			122			122
Period reversals		(971	)		—			—			—			(971	)
Settlements		(2,252	)		(368	)		—			(179	)		(2,799	)
Balance at December 31, 2020	$	—		$	—		$	—		$	—		$	—

Note 11 - Stockholders' Equity - Shares of Common Stock Reserved for Issuance (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Common stock reserved for issuance (in shares)	16,031,282	9,288,870
Options Issued and Outstanding [Member]
Common stock reserved for issuance (in shares)	10,216,106	6,813,033
Options Available for Future Grants [Member]
Common stock reserved for issuance (in shares)	5,582,742	1,230,863
Common Warrants [Member]
Common stock reserved for issuance (in shares)	232,434	1,244,974

Note 4 - Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Text Block]

NOTE 4. Fair Value of Financial Instruments

Fair value accounting is applied for all financial assets and liabilities and nonfinancial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis (at least annually). Financial instruments include cash and cash equivalents, marketable securities, accounts receivable, accounts payable and accrued liabilities that approximate fair value due to their relatively short maturities.

Assets and liabilities recorded at fair value on a recurring basis in the consolidated balance sheets are categorized based upon the level of judgment associated with inputs used to measure their fair values. The accounting guidance for fair value provides a framework for measuring fair value and requires certain disclosures about how fair value is determined. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance also establishes a three-level valuation hierarchy that prioritizes the inputs to valuation techniques used to measure fair value based upon whether such inputs are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions made by the reporting entity.

The three-level hierarchy for the inputs to valuation techniques is briefly summarized as follows:

Level 1 – Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date;

Level 2 – Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and

Level 3 – Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data.

The following table sets forth the fair value of the Company’s financial assets that are measured on a recurring basis as of December 31, 2021 and 2020 (in thousands):

	*Level 1*		*Level 2*		*Level 3*		*Total*
December 31, 2021
Recurring financial assets:
Money market funds	$	70,978	$	—	$	—	$	70,978
U.S. Treasury securities		—		24,997		—		24,997
Commercial paper		—		7,491		—		7,491
Corporate debt securities		—		6,464		—		6,464

Total assets	$	70,978	$	38,952	$	—	$	109,930

	Level 1		Level 2		Level 3		Total
December 31, 2020
Recurring financial assets:
Money market funds	$	60,005	$	—	$	—	$	60,005

Total assets	$	60,005	$	—	$	—	$	60,005

The Company held no financial liabilities measured on a recurring basis as of December 31, 2021 or 2020, or in the years ended December 31, 2021, 2020 or 2019.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Note 12 - Equity Incentive Plans - Total Stock-based Compensation Recognized for Options (Details) - Share-based Payment Arrangement, Option [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock-based compensation	$ 8,867	$ 4,358	$ 627
Research and Development Expense [Member]
Stock-based compensation	4,304	1,563	253
General and Administrative Expense [Member]
Stock-based compensation	$ 4,563	$ 2,795	$ 374

Note 7 - Liabilities Related to Sale of Future Royalties (Tables)

12 Months Ended

Dec. 31, 2021

Deferred Revenue, by Arrangement, Disclosure [Table Text Block]

Total liability related to sale of future royalties, start of year	$	14,929
Non-cash royalty revenue paid to HCRP		(1,098	)
Non-cash interest expense recognized		1,480
Revaluation gain recognized		(3,789	)
Total liability related to sale of future royalties, end of year		11,522
Current portion		(836	)
Long-term portion	$	10,686

Note 4 - Fair Value of Financial Instruments - Financial Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Money Market Funds [Member]
Money market funds, Fair Value	$ 70,978	$ 60,005
Fair Value, Recurring [Member]
Total assets	109,930
Fair Value, Recurring [Member] \| Short-term Investments [Member] \| US Treasury Securities [Member]
Investments, Fair Value Disclosure	24,997
Fair Value, Recurring [Member] \| Short-term Investments [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Investments, Fair Value Disclosure	7,491
Fair Value, Recurring [Member] \| Long-term Investments [Member] \| Corporate Debt Securities [Member]
Investments, Fair Value Disclosure	6,464
Fair Value, Recurring [Member] \| Money Market Funds [Member]
Money market funds, Fair Value	70,978	60,005
Total assets		60,005
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	70,978
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-term Investments [Member] \| US Treasury Securities [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-term Investments [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Long-term Investments [Member] \| Corporate Debt Securities [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Money market funds, Fair Value	70,978	60,005
Total assets		60,005
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	38,952
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-term Investments [Member] \| US Treasury Securities [Member]
Investments, Fair Value Disclosure	24,997
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-term Investments [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Investments, Fair Value Disclosure	7,491
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Long-term Investments [Member] \| Corporate Debt Securities [Member]
Investments, Fair Value Disclosure	6,464
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Money Market Funds [Member]
Money market funds, Fair Value	0	0
Total assets		0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-term Investments [Member] \| US Treasury Securities [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-term Investments [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Long-term Investments [Member] \| Corporate Debt Securities [Member]
Investments, Fair Value Disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Money Market Funds [Member]
Money market funds, Fair Value	$ 0	0
Total assets		$ 0

Note 5 - Balance Sheet Components - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Intangible assets, gross	$ 10,680	$ 20,380
Less: accumulated amortization	(56)	(5,019)
Intangible assets, net	10,624	15,361
Developed Technology Rights [Member]
Intangible assets, gross	10,600	20,300
Intellectual Property [Member]
Intangible assets, gross	$ 80	$ 80

Note 8 - Leases (Details Textual)	12 Months Ended
Note 8 - Leases (Details Textual)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2021	Jul. 31, 2019
Operating Lease, Weighted Average Discount Rate, Percent	9.27%
Operating Lease, Weighted Average Remaining Lease Term (Year)	6 years 11 months 4 days
Lessee, Finance Lease, Number of Leases				0
Operating Lease, Payments	$ 4,400,000	$ 1,100,000	$ 983,000
Right of Use for Office and Manufacturing Facilities with Initial Terms Exceeding One Year [Member]
Lessee, Operating Lease, Number of Right-of-Use Leases	5
Right of Use for Equipment with Initial Terms Exceeding One Year [Member]
Lessee, Operating Lease, Number of Right-of-Use Leases	1
Leases for Manufacturing Facilities with Initial Terms of One Year or Less [Member]
Lessee, Short-term Lease, Number of Leases	3
Lease Agreements for Manufacturing Equipment with Initial Terms of One Year or Less [Member]
Lessee, Short-term Lease, Number of Leases	1
South San Francisco Real Estate [Member]
Lessee, Operating Lease, Renewal Term (Year)	8 years				5 years
Facility in South San Francisco [Member]
Lessee, Operating Lease, Renewal Term (Year)	5 years
Facility in Burlingame, California [Member]
Lessee, Operating Lease, Renewal Term (Year)	30 months
Lessee, Operating Lease, Number of Renewal Option	2
Gain (Loss) on Termination of Lease	$ 116,000
Facilities Under Operating Leases [Member]
Short-term Lease Commitment, Amount	14,000
Equipment Under Operating Leases [Member]
Short-term Lease Commitment, Amount	$ 8,000

Note 18 - Quarterly Financial Data (Unaudited) - Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue	$ 74	$ 200	$ 112	$ 506	$ 356	$ 265	$ 523	$ 2,902	$ 3,916	$ 454	$ 85	$ 5,407	$ 892	$ 4,046	$ 9,862
Operating expenses	24,289	17,451	15,887	16,017	13,717	7,854	9,049	3,596	9,542	5,168	5,082	5,855	73,644	34,216	25,647
Net loss	$ (20,764)	$ (17,583)	$ (16,116)	$ (16,007)	$ (13,861)	$ (8,085)	$ (8,977)	$ (1,297)	$ (6,409)	$ (5,260)	$ (5,637)	$ (1,339)	$ (70,470)	$ (32,220)	$ (18,645)
Net loss per share – basic and diluted (in dollars per share)	$ (0.17)	$ (0.14)	$ (0.13)	$ (0.14)	$ (0.13)	$ (0.08)	$ (0.12)	$ (0.02)	$ (0.13)	$ (0.32)	$ (0.39)	$ (0.18)	$ (0.58)	$ (0.36)	$ (0.86)

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

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9038-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130545-203045

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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130543-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9031-108599

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

Note 11 - Stockholders' Equity (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Mar. 02, 2020	Sep. 30, 2019	Apr. 11, 2019	Mar. 20, 2019
Preferred Stock, Shares Authorized (in shares)	5,000,000	5,000,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.0001	$ 0.0001
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0	0
Dividends, Total	$ 0
Warrants in Connection with March 2019 Offering [Member]
Warrants and Rights Outstanding						$ 100,000
The March 2020 Offering Placement Agent Warrants [Member]
Warrants and Rights Outstanding			$ 453,000
Warrants in Connection With the April 2019 Offering [Member]
Warrants and Rights Outstanding					$ 333,000
Underwriter Warrants, September 2019 [Member]
Warrants and Rights Outstanding				$ 497,000
First Set of Warrants Expiring September 2024 [Member]
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction (in dollars per share)	$ 0.30
First Set of Warrants Expiring April 2024 [Member]
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction (in dollars per share)	1.10
Warrants Expiring March 2025 [Member]
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction (in dollars per share)	2.50
Warrants Expiring February 2025 [Member]
Warrant Exercise Price to be Entitled to Receive Cash Consideration, Fundamental Transaction (in dollars per share)	$ 3.125

Note 8 - Leases - Lease Liabilities Payment Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
2022	$ 2,071
2023	2,123
2024	2,195
2025	2,297
2026	2,852
Thereafter	6,770
Undiscounted total	18,308
Less: imputed interest	(5,300)
Present value of future minimum payments	13,008
Current portion of operating lease liability	(1,011)	$ (2,052)
Operating lease liability, net of current portion	$ 11,997	$ 5,156

Note 1 - Organization and Basis of Presentation

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

NOTE 1. Organization and Basis of Presentation

General

Vaxart Biosciences, Inc. was originally incorporated in California in March 2004, under the name West Coast Biologicals, Inc. The Company changed its name to Vaxart, Inc. (“Private Vaxart”) in July 2007, and reincorporated in the state of Delaware. In February 2018, Private Vaxart completed a business combination with Aviragen Therapeutics, Inc. (“Aviragen”), pursuant to which Aviragen merged with Private Vaxart, with Private Vaxart surviving as a wholly-owned subsidiary of Aviragen (the “Merger”). Pursuant to the terms of the Merger, Aviragen changed its name to Vaxart, Inc. (together with its subsidiaries, the “Company” or “Vaxart”) and Private Vaxart changed its name to Vaxart Biosciences, Inc.

On March 20, 2019, the Company completed a registered direct offering (the “March 2019 Offering”) of 1,200,000 shares of the Company’s common stock. The total gross proceeds from the offering to the Company were $3.0 million. After deducting placement agent fees and offering expenses payable by the Company, the aggregate net proceeds received by the Company totaled $2.5 million. Pursuant to the terms of the engagement letter with the placement agents, the Company paid the placement agents aggregate fees and reimbursable costs of $320,000. In addition, the Company issued the placement agents’ designees 84,000 common stock warrants at the closing of the March 2019 Offering, each warrant entitling the holder to purchase one share of common stock for $3.125 at any time within five years of the effective date of the March 2019 Offering. The aggregate fair value of these warrants at issuance was estimated to be $100,000 (see Note 11), which was recorded in offering costs. As of December 31, 2021, the Company had received $0.2 million from the exercise of 67,825 common stock warrants issued to placement agents’ designees in the March 2019 Offering.

On April 11, 2019, the Company completed a public underwritten offering (the “April 2019 Offering”) of 925,455 shares of common stock, 8,165,455 pre-funded warrants, and warrants to purchase 10,454,546 shares of common stock (including 1,363,636 common stock warrants issued upon the exercise by the underwriters of their option to purchase such warrants). Each share of common stock with an accompanying common stock warrant was sold for $1.10, and each pre-funded warrant with an accompanying common stock warrant was sold for $1.00, with the amount paid for each accompanying common stock warrant being $0.10. Each pre-funded warrant entitled the holder to purchase one share of common stock for $0.10, was immediately exercisable, subject to certain ownership limitations, and was exercisable at any time until all the pre-funded warrants were exercised in full. Each common stock warrant entitles the holder to purchase one share of common stock for $1.10, is exercisable immediately, subject to certain ownership limitations, and will expire five years from the date of issuance.

Pursuant to the terms of an underwriting agreement, the Company paid the underwriters aggregate commissions and reimbursable costs of $750,000. In addition, the Company issued the underwriters’ designees 636,364 common stock warrants at the closing of the April 2019 Offering, each warrant entitling the holder to purchase one share of common stock for $1.375 at any time within five years of their issuance date. The aggregate fair value of these warrants at issuance was estimated to be $333,000 (see Note 11), which was recorded in offering costs.

The total gross proceeds from the April 2019 Offering to the Company were $9.3 million. After deducting underwriting discounts, commissions and offering expenses payable by the Company, the aggregate net proceeds received by the Company were $8.1 million. In addition, as of December 31, 2021, the Company had received a further $0.8 million from the exercise of all 8,165,455 pre-funded warrants, $11.5 million from the exercise of 10,410,398 common stock warrants issued to investors and $0.8 million from the exercise of 609,849 common stock warrants issued to underwriters’ designees issued in the April 2019 Offering.

On September 30, 2019, the Company completed a public underwritten offering (the “September 2019 Offering”) of 26,124,828 shares of common stock (including 3,558,161 shares of common stock issued upon the partial exercise by the underwriters of their option to purchase 4,000,000 shares), 4,100,000 pre-funded warrants, and warrants to purchase 30,666,667 shares of common stock (including 4,000,000 common stock warrants issued upon the exercise by the underwriters of their option to purchase such warrants). Each share of common stock with an accompanying common stock warrant was sold for $0.30, and each pre-funded warrant with an accompanying common stock warrant was sold for $0.20, with the amount paid for each accompanying common stock warrant being $0.10. Each pre-funded warrant entitled the holder to purchase one share of common stock for $0.10, was immediately exercisable, subject to certain ownership imitations, and was exercisable at any time until all the pre-funded warrants were exercised in full. Each common stock warrant entitles the holder to purchase one share of common stock for $0.30, is exercisable immediately, subject to certain ownership limitations, and will expire five years from the date of issuance.

Pursuant to the terms of an underwriting agreement, the Company paid the underwriters aggregate commissions and reimbursable costs of $713,000. In addition, the Company issued the underwriters’ designees 2,115,738 common stock warrants at the closing of the September 2019 Offering, each warrant entitling the holder to purchase one share of common stock for $0.375 at any time within five years of their issuance date. The aggregate fair value of these warrants at issuance was estimated to be $497,000 (see Note 11), which was recorded in offering costs.

The total gross proceeds from the September 2019 Offering to the Company were $8.7 million. After deducting underwriting discounts, commissions and offering expenses payable by the Company, the aggregate net proceeds received by the Company were $7.7 million. In addition, as of December 31, 2021, the Company had received $0.4 million from the exercise of all 4,100,000 pre-funded warrants, $9.2 million from the exercise of 30,661,667 common stock warrants issued to investors and $0.8 million from the exercise of all 2,115,738 common stock warrants issued to underwriters’ designees in the September 2019 Offering.

On March 2, 2020, the Company completed a registered direct offering (the “March 2020 Offering”) of 4,000,000 shares of the Company’s common stock and warrants to purchase 2,000,000 shares of common stock. Each common stock warrant entitles the holder to purchase one share of common stock for $2.50, is exercisable immediately, subject to certain ownership limitations, and will expire five years from the date of issuance. Pursuant to the terms of the engagement letter with the placement agents, the Company paid the placement agents aggregate fees and reimbursable costs of $775,000. In addition, the Company issued the placement agents’ designees 280,000 common stock warrants at the closing of the March 2020 Offering, each warrant entitling the holder to purchase one share of common stock for $3.125 at any time within five years of the effective date of the March 2020 Offering. The aggregate fair value of these warrants at issuance was estimated to be $453,000 (see Note 11), which was recorded in offering costs.

The total gross proceeds from the March 2020 Offering to the Company were $10.0 million. After deducting placement agent fees and offering expenses payable by the Company, the aggregate net proceeds received by the Company totaled $9.2 million. In addition, as of December 31, 2021, the Company had received $4.9 million from the exercise of 1,970,850 common stock warrants issued to investors and $0.6 million from the exercise of 179,468 common stock warrants issued to placement agents’ designees in the March 2020 Offering.

On June 8, 2020, the Company’s shareholders approved an amendment to the Company’s certificate of incorporation to change the par value of its common and preferred stock from $0.10 per share to $0.0001 per share and to increase the number of authorized shares of common stock from 100,000,000 to 150,000,000. Except as otherwise noted in these consolidated financial statements, all share, equity security and per share amounts are presented to give retroactive effect to these changes.

On July 13, 2020, the Company completed the sale of 12,503,806 shares for gross proceeds of $100.0 million from an at-the-market facility (the “ATM Program”) under a sales prospectus agreement dated July 8, 2020. After deducting sales commissions and expenses, aggregate net cash proceeds under the ATM Program totaled $97.0 million.

On October 13, 2020, the Company entered into the Open Market Sale Agreement, (the “October 2020 ATM”) pursuant to which it could offer and sell, from time to time through sales agents, shares of its common stock having an aggregate offering price of up to $250 million. The Company incurred direct expenses of approximately $0.3 million in connection with filing a prospectus supplement, dated October 13, 2020, with the U.S. Securities and Exchange Commission (the “SEC”), and paid sales commissions of up to 4.5% of gross proceeds from the sale of shares. As of December 31, 2020, the Company had sold 692,651 shares for gross proceeds of $5.5 million which, after deducting sales commissions and expenses, resulted in net proceeds under the October 2020 ATM of $4.9 million in 2020.

In the year ended December 31, 2021, the Company sold an additional 13,239,839 shares under the October 2020 ATM for gross proceeds of $127.9 million which, after deducting sales commissions and expenses, resulted in net proceeds under the October 2020 ATM of $122.2 million. As of December 31, 2021, a total of 13,932,490 shares had been issued and sold under the October 2020 ATM since its inception for gross proceeds of $133.4 million which, after deducting sales commissions and expenses, resulted in net proceeds of $127.1 million.

On September 13, 2021, the October 2020 ATM was terminated and on September 15, 2021, the Company entered into a Controlled Equity Offering Sales Agreement (the “September 2021 ATM”), pursuant to which it may offer and sell, from time to time through sales agents, shares of its common stock having an aggregate offering price of up to $100 million. The Company incurred direct expenses of approximately $0.2 million in connection with filing a prospectus supplement with the SEC on September 16, 2021, and will pay sales commissions of up to 3.0% of gross proceeds from the sale of shares. As of December 31, 2021, no shares had been issued under the September 2021 ATM.

The Company’s principal operations are based in South San Francisco, California, and it operates in one reportable segment, which is the discovery and development of oral recombinant protein vaccines, based on its proprietary oral vaccine platform.

Note 12 - Equity Incentive Plans - Summary of Stock Option Transactions (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Shares available for grant, balance (in shares)	1,230,863	295,180	200,650
Number of options outstanding, beginning balance (in shares)	6,813,033	1,811,652	865,163
Weighted average exercise price, balance (in dollars per share)	$ 2.70	$ 2.74	$ 8.13
Shares availabe for grant, 2019 Plan Amendment (in shares)	8,900,000	6,400,000	1,600,000
Shares available for grant, removed from 2016 Plan (in shares)			(223,389)
Shares available for grant, granted (in shares)	(5,178,438)	(5,579,800)	(1,791,030)
Number of options outstanding, granted (in shares)	5,178,438	5,579,800	1,791,030
Weighted average exercise price, granted (in dollars per share)	$ 7.09	$ 2.66	$ 0.67
Shares available for grant, forfeited (in shares)	630,317	105,910	483,849
Number of options outstanding, forfeited (in shares)	(650,054)	(105,992)	(592,528)
Weighted average exercise price, forfeited (in dollars per share)	$ 3.16	$ 1.65	$ 1.57
Shares available for grant, canceled (in shares)	0	9,573	25,100
Number of options outstanding, canceled (in shares)	(54,390)	(57,751)	(252,013)
Weighted average exercise price, canceled (in dollars per share)	$ 11.98	$ 10.57	$ 9.25
Number of options outstanding, exercised (in shares)	(1,070,921)	(414,676)	0
Weighted average exercise price, exercised (in dollars per share)	$ 1.63	$ 1.45
Shares available for grant, balance (in shares)	5,582,742	1,230,863	295,180
Number of options outstanding, balance (in shares)	10,216,106	6,813,033	1,811,652
Weighted average exercise price, balance (in dollars per share)	$ 4.96	$ 2.70	$ 2.74

Note 17 - Net Loss Per Share Attributable to Common Stockholders - Summary of Antidilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	8,575,180	19,183,231	19,163,520
Share-based Payment Arrangement, Option [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	8,206,137	4,409,806	1,583,575
Warrant [Member] \| Common Stock [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	369,043	14,773,425	17,579,945

Note 9 - Secured Promissory Note Payable to Oxford Finance

12 Months Ended

Dec. 31, 2021