Note 5 - Balance Sheet Components

12 Months Ended

Dec. 31, 2021

Notes to Financial Statements

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