Note 7 - Net Loss Per Share

12 Months Ended

Dec. 31, 2017

Notes to Financial Statements

Earnings Per Share [Text Block]

7.

Net Loss Per Share

The following summarizes the computation of basic and diluted net loss per share for the years ended

December 31, 2017,

2016

and

2015

(in thousands, except share and per share data):

	Year Ended December 31,
	2017			2016			2015
Net loss	$	(33,150	)	$	(52,761	)	$	(37,483	)
Weighted-average number of common shares—basic and diluted		34,875,814			32,403,391			30,801,994
Net loss per share—basic and diluted	$	(0.95	)	$	(1.63	)	$	(1.22	)

The following potentially dilutive securities outstanding, prior to the use of the treasury stock method or if-converted method, have been excluded from the computation of diluted weighted-average common shares outstanding, because including them would have had an anti-dilutive effect due to the losses reported.

	Year Ended December 31,
	2017		2016		2015
Stock options		5,303,624		5,188,658		4,786,577
Warrants to purchase common stock		-		-		-
Total		5,303,624		5,188,658		4,786,577