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	51									51
Exercise of stock options, Shares					7,780
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
Exercise of warrants	2									2
Exercise of warrants, Shares					250
Stock-based compensation expense	6,623									6,623
Other comprehensive gain (loss)	24													24
Net loss	(55,709)														(55,709)
Balance at Sep. 30, 2019	94,574				$ 43					367,764				21	(273,254)
Balance (in shares) at Sep. 30, 2019					42,441,227
Balance (in shares) at Sep. 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 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
Exercise of stock options	45									45
Exercise of stock options, Shares					5,480
Exercise of warrants	2									2
Exercise of warrants, Shares					250
Stock-based compensation expense	2,388									2,388
Other comprehensive gain (loss)	17													17
Net loss	(19,793)														(19,793)
Balance at Sep. 30, 2019	94,574				$ 43					367,764				21	(273,254)
Balance (in shares) at Sep. 30, 2019					42,441,227
Balance (in shares) at Sep. 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	$ 509									509
Exercise of stock options, Shares	95,647				95,647
Vesting of restricted stock units					105,912
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	7,909									7,909
Other comprehensive gain (loss)	(24)													$ (24)
Net loss	(53,908)														(53,908)
Balance at Sep. 30, 2020	$ 45,940				$ 45					392,786					(346,891)
Balance (in shares) at Sep. 30, 2020	45,807,878				45,807,878
Balance (in shares) at Sep. 30, 2020	0
Balance at Jun. 30, 2020	$ 62,406				$ 45					389,766					(327,405)
Balance (in shares) at Jun. 30, 2020					45,758,881
Exercise of stock options	297									297
Exercise of stock options, Shares					46,547
Vesting of restricted stock units					2,450
Stock-based compensation expense	2,723									2,723
Net loss	(19,486)														(19,486)
Balance at Sep. 30, 2020	$ 45,940				$ 45					$ 392,786					$ (346,891)
Balance (in shares) at Sep. 30, 2020	45,807,878				45,807,878
Balance (in shares) at Sep. 30, 2020	0