Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 160,814	$ 40,326
Investment securities	44,351	78,066
Prepaid expenses and other current assets	5,445	4,947
Total current assets	210,610	123,339
Property and equipment, net	3,635	3,946
Operating lease right-of-use asset	2,377	2,510
Restricted cash	500	500
Other assets		82
Total assets	217,122	130,377
Current liabilities:
Accounts payable and accrued expenses	6,760	5,498
Accrued compensation and related expenses	2,328	2,118
Other current liabilities	782	724
Total current liabilities	9,870	8,340
Operating lease liability, non-current	4,444	4,849
Unvested stock liability	34	49
Total liabilities	14,348	13,238
Commitments and contingencies (Note 7)
Stockholders’ equity:
Preferred stock, $0.001 par value; 10,000 shares authorized; no shares issued or outstanding at June 30, 2020 or at December 31, 2019
Common stock and paid-in capital, $0.001 par value; 200,000 shares authorized; 32,906 shares issued and 32,882 shares outstanding at June 30, 2020; 24,296 shares issued and 24,263 shares outstanding at December 31, 2019	330,300	210,793
Accumulated other comprehensive income	127	148
Accumulated deficit	(127,653)	(93,802)
Total stockholders’ equity	202,774	117,139
Total liabilities and stockholders’ equity	$ 217,122	$ 130,377