Balance Sheet Information

12 Months Ended

Dec. 31, 2023

Disclosure Text Block Supplement [Abstract]

3. BALANCE SHEET INFORMATION

Cash, cash equivalents and restricted cash

Cash, cash equivalents and restricted cash consisted of the following as of December 31 (in thousands):


	2023		2022
Cash and cash equivalents	$	25,124	$	71,038
Restricted cash, non-current		2,348		2,767
Total cash, cash equivalents and restricted cash	$	27,472	$	73,805

As of December 31, 2023 and 2022, non-current restricted cash primarily consisted of security deposits on the Company’s operating leases.

Property and equipment

Property and equipment, net consisted of the following as of December 31 (in thousands):


	2023			2022
Leasehold improvements	$	—		$	13,972
Software		—			4,883
Lab equipment		—			4,146
Office furniture and fixtures		869			1,406
Computer equipment		—			499
Construction work-in-progress		—			316
Total		869			25,222
Less: Accumulated depreciation		(275	)		(9,286	)
Property and equipment, net	$	594		$	15,936

Depreciation and amortization expenses were $1.5 million and $5.5 million for the years ended December 31, 2023 and 2022, respectively. For the year ended December 31, 2023, as a result of focusing solely on objectives to realize the value of the Company’s intellectual property estate, all of the Company’s property and equipment, other than certain office furniture and fixtures, was sold, donated or abandoned. The property and equipment was sold for $1.3 million, resulting in a gain of $0.6 million, which was included as a separate charge within other income, net on the Company’s consolidated statements of operations for the year ended December 31, 2023.

Accrued expenses

Accrued expenses and other current liabilities consisted of the following as of December 31 (in thousands):


	2023		2022
Legal and professional fees	$	1,301	$	5,852
Research and development costs		—		1,967
Refundable tax credit		418		868
Restructuring costs		260		201
Accrued compensation and benefits		125		680
Accrued other		116		593
Total accrued expenses and other current liabilities	$	2,220	$	10,161