The following tables present changes in stockholders’ equity for the six-month periods ended June 30, 2020 and 2019 (in thousands, except share data):

					Additional		Accumulated Other						Total
	Common				Paid-In		Comprehensive			Accumulated			Stockholders’
	Shares		Amount		Capital		Income (Loss)			Deficit			Equity
Balance at December 31, 2019		50,198,044	$	5	$	570,493	$	261		$	(300,878	)	$	269,881
Issuance of common stock through at-the-market offerings, net of issuance costs of $48		351,252		-		5,079		-			-			5,079
Exercise of stock options		53,579		-		336		-			-			336
Equity-based compensation		-		-		4,157		-			-			4,157
Other comprehensive income		-		-		-		112			-			112
Net loss		-		-		-		-			(31,806	)		(31,806	)
Balance at March 31, 2020		50,602,875		5		580,065		373			(332,684	)		247,759
Issuance of common stock through follow-on offering, net of issuance costs of $369		6,301,370		1		107,731		-			-			107,732
Issuance of common stock in private placement with Regeneron		925,218		-		12,580		-			-			12,580
Issuance of common stock through at-the-market offerings, net of issuance costs of $23		755,848		-		9,643		-			-			9,643
Exercise of stock options		83,631		-		1,035		-			-			1,035
Issuance of shares under employee stock purchase plan		55,296		-		685		-			-			685
Equity-based compensation		-		-		4,764		-			-			4,764
Other comprehensive loss		-		-		-		(218	)		-			(218	)
Net loss		-		-		-		-			(32,393	)		(32,393	)
Balance at June 30, 2020		58,724,238	$	6	$	716,503	$	155		$	(365,077	)	$	351,587

					Additional		Accumulated Other						Total
	Common				Paid-In		Comprehensive			Accumulated			Stockholders’
	Shares		Amount		Capital		(Loss) Income			Deficit			Equity
Balance at December 31, 2018		45,224,480	$	5	$	478,968	$	(28	)	$	(201,025	)	$	277,920
Retroactive adjustment to beginning accumulated deficit for adoption of ASC 842		-		-		-		-			(320	)		(320	)
Issuance of common stock through at-the-market offerings, net of issuance costs of $120		223,818		-		3,639		-			-			3,639
Exercise of stock options		30,800		-		360		-			-			360
Equity-based compensation		-		-		4,592		-			-			4,592
Other comprehensive income		-		-		-		87			-			87
Net loss		-		-		-		-			(21,940	)		(21,940	)
Balance at March 31, 2019		45,479,098		5		487,559		59			(223,285	)		264,338
Issuance of common stock through at-the-market offerings, net of issuance costs of $3		1,986,579		-		31,413		-			-			31,413
Exercise of stock options		203,072		-		1,664		-			-			1,664
Issuance of shares under employee stock purchase plan		45,826		-		534		-			-			534
Equity-based compensation		-		-		4,404		-			-			4,404
Other comprehensive income		-		-		-		196			-			196
Net loss		-		-		-		-			(25,683	)		(25,683	)
Balance at June 30, 2019		47,714,575	$	5	$	525,574	$	255		$	(248,968	)	$	276,866