Quarterly report pursuant to Section 13 or 15(d)

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY - USD ($) $ in Thousands	Total	At The Market	Follow On Offering Common Stock and Warrants	Follow On Offering Preferred Stock and Warrants	Common Stock	Common Stock At The Market	Common Stock Follow On Offering Common Stock and Warrants	Series A Convertible Preferred Stock	Series A Convertible Preferred Stock Follow On Offering Preferred Stock and Warrants	Additional Paid-In Capital	Additional Paid-In Capital At The Market	Additional Paid-In Capital Follow On Offering Common Stock and Warrants	Additional Paid-In Capital Follow On Offering Preferred Stock and Warrants	Accumulated Other Comprehensive (Loss) Gain	Accumulated Deficit
Balance at Dec. 31, 2018	$ 78,586				$ 34					$ 296,100				$ (3)	$ (217,545)
Balance (in shares) at Dec. 31, 2018					33,765,864
Exercise of stock options	7									7
Exercise of stock options, Shares					2,300
Issuance of common stock / preferred stock, net of issuance costs			$ 60,359	$ 4,638			$ 9					$ 60,350	$ 4,638
Issuance of common stock / preferred stock, net of issuance costs (in shares)							8,667,333		666
Stock-based compensation expense	4,234									4,234
Other comprehensive gain (loss)	7													7
Net loss	(35,916)														(35,916)
Balance at Jun. 30, 2019	111,915				$ 43					365,329				4	(253,461)
Balance (in shares) at Jun. 30, 2019					42,435,497
Balance (in shares) at Jun. 30, 2019								666
Balance at Dec. 31, 2018	78,586				$ 34					296,100				(3)	(217,545)
Balance (in shares) at Dec. 31, 2018					33,765,864
Net loss	(75,400)
Balance at Dec. 31, 2019	$ 79,184				$ 43					372,100				24	(292,983)
Balance (in shares) at Dec. 31, 2019	43,367,801				43,367,801
Balance (in shares) at Dec. 31, 2019	0
Balance at Mar. 31, 2019	$ 64,018				$ 34					297,982				8	(234,006)
Balance (in shares) at Mar. 31, 2019					33,766,941
Exercise of stock options	3									3
Exercise of stock options, Shares					1,223
Issuance of common stock / preferred stock, net of issuance costs			$ 60,359	$ 4,638			$ 9					$ 60,350	$ 4,638
Issuance of common stock / preferred stock, net of issuance costs (in shares)							8,667,333		666
Stock-based compensation expense	2,356									2,356
Other comprehensive gain (loss)	(4)													(4)
Net loss	(19,455)														(19,455)
Balance at Jun. 30, 2019	111,915				$ 43					365,329				4	(253,461)
Balance (in shares) at Jun. 30, 2019					42,435,497
Balance (in shares) at Jun. 30, 2019								666
Balance at Dec. 31, 2019	$ 79,184				$ 43					372,100				24	(292,983)
Balance (in shares) at Dec. 31, 2019	43,367,801				43,367,801
Balance (in shares) at Dec. 31, 2019	0
Exercise of stock options	$ 212									212
Exercise of stock options, Shares	49,100				49,100
Vesting of restricted stock units					103,462
Issuance of common stock / preferred stock, net of issuance costs		$ 11,919				$ 2					$ 11,917
Issuance of common stock / preferred stock, net of issuance costs (in shares)						2,201,810
Issuance of shares under Employee Stock Purchase Plan	$ 223									223
Issuance of shares under Employee Stock Purchase Plan, shares					36,708
Issuance of warrants	128									128
Stock-based compensation expense	5,186									5,186
Other comprehensive gain (loss)	(24)													(24)
Net loss	(34,422)														(34,422)
Balance at Jun. 30, 2020	$ 62,406				$ 45					389,766					(327,405)
Balance (in shares) at Jun. 30, 2020	45,758,881				45,758,881
Balance (in shares) at Jun. 30, 2020	0
Balance at Mar. 31, 2020	$ 76,543				$ 45					386,704				3	(310,209)
Balance (in shares) at Mar. 31, 2020					45,690,718
Exercise of stock options	112									112
Exercise of stock options, Shares					18,505
Vesting of restricted stock units					12,950
Issuance of shares under Employee Stock Purchase Plan	223									223
Issuance of shares under Employee Stock Purchase Plan, shares					36,708
Stock-based compensation expense	2,727									2,727
Other comprehensive gain (loss)	(3)													$ (3)
Net loss	(17,196)														(17,196)
Balance at Jun. 30, 2020	$ 62,406				$ 45					$ 389,766					$ (327,405)
Balance (in shares) at Jun. 30, 2020	45,758,881				45,758,881
Balance (in shares) at Jun. 30, 2020	0