4. Balance Sheet Components

Property and Equipment, net

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



	March 31,		December 31,
	2020		2019
Leasehold improvements	$	2,248	$	2,248
Laboratory equipment		677		677
Furniture, fixtures, and equipment		466		466
Software		118		118
Construction in progress		714		543
		4,223		4,052
Less: Accumulated depreciation		(1,590)		(1,486)
	$	2,633	$	2,566

Depreciation expense was $0.1 million for the three-month periods ended March 31, 2020 and 2019, respectively.

Intangible Assets, Net

Intangible assets primarily consist of acquired licenses to utilize certain patents, know-how and technology relating to the Company’s NPS for biomedical applications acquired from Old Dominion University Research Foundation (ODURF), Eastern Virginia Medical School, and the University of Southern California. In addition, the Company entered into a Sponsored Research Agreement with Old Dominion University’s Frank Reidy Research Center for Bioelectrics, which includes certain intellectual property rights arising from the research. The Company is amortizing the intangible assets over an estimated useful life of 12 years.

Intangible assets, net consisted of the following (in thousands):



	March 31,		December 31,
	2020		2019
Acquired patents and licenses	$	7,985	$	7,985
Less: Accumulated amortization		(3,604)		(3,438)
	$	4,381	$	4,547

A schedule of the amortization of intangible assets for the remainder of 2020 and the succeeding five fiscal years and thereafter is as follows (in thousands):


Year Ending December 31:
2020 (remaining 9 months)	$	499
2021		665
2022		665
2023		665
2024		665
2025		665
Thereafter		557
	$	4,381

Accrued Expenses

Accrued expenses consisted of the following (in thousands):



	March 31,		December 31,
	2020		2019
Compensation expense	$	1,172	$	1,699
Accrued clinical		512		262
Professional fees		37		51
Property and equipment		234		234
Other		116		250
	$	2,071	$	2,496