Supplemental Balance Sheet Information (Tables)

3 Months Ended

Mar. 31, 2020

Supplemental Balance Sheet Information [Abstract]

Prepaid Expense and Other Current Assets

Prepaid expenses and other current assets

	March 31, 2020		December 31, 2019
Prepaid clinical, contract research and manufacturing costs	$	1,219	$	481
Interest receivable	398		236
Prepaid insurance	369		533
Other	920		705
Prepaid expenses and other current assets	$	2,906	$	1,955

Property and Equipment, Net

Property and equipment, net

	March 31, 2020			December 31, 2019
Scientific equipment	$	3,315		$	2,795
Leasehold improvements	192			192
Computers and software	48			32
Furniture and fixtures	41			41
Construction in process	168			356
Property and equipment, gross	3,764			3,416
Less: accumulated depreciation	(1,466		)	(1,317		)
Property and equipment, net	$	2,298		$	2,099

Other Noncurrent Assets

Other noncurrent assets

	March 31, 2020		December 31, 2019
Restricted cash	$	1,200	$	—
Operating lease asset	285		356
Other	2		32
Total other noncurrent assets	$	1,487	$	388

Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities

	March 31, 2020		December 31, 2019
Accrued payroll-related expenses	$	386	$	920
Accrued legal expenses	318		254
Operating lease liability	275		292
Accrued clinical, contract research and manufacturing costs	152		515
Accrued other expenses	137		454
Accrued expenses and other current liabilities	$	1,268	$	2,435

Other Noncurrent Liabilities

Other noncurrent liabilities

	March 31, 2020		December 31, 2019
Operating lease liability	$	—	$	59
Total other noncurrent liabilities	$	—	$	59