Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2020

Stockholders' Equity

Schedule of allocation of stock-based compensation expense

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2020		2019		2020		2019
Research and development	$	139	$	159	$	337	$	310
General and administrative		700		320		1,123		659
Total	$	839	$	479	$	1,460	$	969