Selected quarterly financial data for years ended December 31, 2019 and 2018, are as follows (in thousands, except share and per share amounts):


	Quarter Ended
	March 31, 2019		June 30, 2019		September 30, 2019		December 31, 2019
Net product sales	$	14,634	$	15,643	$	17,540	$	16,832
Gross profit		8,238		10,544		11,093		9,651
Net loss attributable to common stock	$	(7,600)	$	(3,763)	$	(2,051)	$	(3,488)
Weighted average common shares outstanding used to compute net loss per share, basic and diluted (1)		49,703,563		49,727,718		49,730,755		49,732,654
Net loss per share of common stock, basic and fully diluted (2):	$	(0.15)	$	(0.08)	$	(0.04)	$	(0.07)


	Quarter Ended
	March 31, 2018		June 30, 2018		September 30, 2018		December 31, 2018
Net product sales	$	10,729	$	11,363	$	12,503	$	15,393
Gross profit		5,508		4,376		5,546		7,631
Net loss attributable to common stock	$	(14,436)	$	(15,207)	$	(12,695)	$	(9,337)
Weighted average common shares outstanding used to compute net loss per share, basic and diluted (1)		28,996,956		29,008,909		29,625,792		41,415,358
Net loss per share of common stock, basic and fully diluted (2):	$	(0.50)	$	(0.52)	$	(0.43)	$	(0.23)

(1)

On November 8, 2018, the Company closed an underwritten public offering of 19,999,999 shares of its common stock at a public offering price of $2.30 per share, which includes 2,608,695 shares of its common stock resulting from the underwriters’ exercise of their over-allotment option at the public offering price. In addition, in 2018, the Company sold 651,525 shares of common stock under the Cowen Sales Agreement, at an average sale price of approximately $6.25 per share. These transactions produced a significant increase in the number of shares outstanding which will impact the year-over-year comparability of the Company’s loss per share calculations.

Loss per share is computed independently for each of the quarters presented. Therefore, the sum of the quarterly loss per share may not necessarily equal the total for the year.