Note 4 - Balance Sheet Components

6 Months Ended

Jun. 30, 2021

Notes to Financial Statements

Supplemental Balance Sheet Disclosures [Text Block]

NOTE 4.  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
June 30, 2021
Cash at banks	$	88,955	$	—	$	—		$	88,955	$	88,955	$	—	$	—
Money market funds		76,311		—		—			76,311		76,311		—		—
U.S. Treasury securities		19,038		—		(6	)		19,032		—		9,996		9,036
Commercial paper		7,192		—		—			7,192		—		7,192		—
Corporate debt securities		7,436		—		(3	)		7,433		—		2,130		5,303
Total	$	198,932	$	—	$	(9	)	$	198,923	$	165,266	$	19,318	$	14,339

	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 $107,000 and $334,000 as of June 30, 2021 and December 31, 2020, respectively. The Company has provided no allowance for uncollectible accounts as of  June 30, 2021 and December 31, 2020.

(c) Property and Equipment, Net

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

	June 30, 2021			December 31, 2020
Laboratory equipment	$	2,199		$	1,759
Office and computer equipment		325			294
Construction in progress		2,583			—
Total property and equipment		5,107			2,053
Less: accumulated depreciation		(768	)		(573	)
Property and equipment, net	$	4,339		$	1,480

Depreciation expense was $120,000 and $25,000 for the three months ended June 30, 2021 and 2020, respectively, and $195,000 and $44,000 for the six months ended June 30, 2021 and 2020, respectively. There were no impairments of the Company’s property and equipment recorded in the six months ended June 30, 2021 or 2020.

(d) Right-of-Use Assets, Net

Right-of-use assets, net consists of the following (in thousands):

	June 30, 2021		December 31, 2020
Facilities	$	5,807	$	6,836
Office equipment		1		2
Right-of-use assets, net	$	5,808	$	6,838

(e) Intangible Assets, Net

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. As of June 30, 2021, developed technology and intellectual property had remaining lives of 8.4 and 6.5 years, respectively. Intangible assets consist of the following (in thousands):

	June 30, 2021			December 31, 2020
Purchased technology	$	20,300		$	20,300
Intellectual property		80			80
Total cost		20,380			20,380
Less: accumulated amortization		(5,885	)		(5,019	)
Intangible assets, net	$	14,495		$	15,361

Total amortization expense for the three months ended June 30, 2021 and 2020, was $433,000, and for the six months ended June 30, 2021 and 2020, was $866,000. As of June 30, 2021, the estimated future amortization expense by year is as follows (in thousands):

Year Ending December 31,	Amount
2021 (six months remaining)	$	866
2022		1,731
2023		1,732
2024		1,732
2025		1,731
Thereafter		6,703
Total	$	14,495

(f) Other Accrued Liabilities

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

	June 30, 2021		December 31, 2020
Accrued compensation	$	1,508	$	1,618
Accrued clinical and manufacturing expenses		1,175		1,772
Accrued professional and consulting services		1,060		777
Other liabilities, current portion		394		632
Total	$	4,137	$	4,799