Accrued expenses (Tables)

12 Months Ended

Dec. 31, 2018

Accrued expenses

Schedule of accrued expenses

Accrued expenses consist of the following:

	As of December 31,
	2018		2017
	(in thousands)
Employee compensation costs	$	3,780	$	3,383
Research and development costs		3,555		5,780
Professional services		1,448		1,762
Accrued goods and services		784		388
Patent costs		120		120
Other		101		64
Total	$	9,788	$	11,497