Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Schedule of Estimated Stock-Based Compensation Expense

Stock-based compensation expense, net of estimated forfeitures, is reflected in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands):

	Three Months Ended
	March 31,
	2019		2018
Operating Expenses
Research and development	$	86	$	882
General and administrative		962		1,938
Total	$	1,048	$	2,820