Three Months Ended

March 31, 2017

June 30, 2017

September 30, 2017

December 31, 2017

Revenue

$

1,101

$

 —

$

 —

$

 —

Operating expenses:

Research and development

9,628

10,041

10,447

11,780

General and administrative

3,086

3,472

3,593

3,740

Total operating expenses

12,714

13,513

14,040

15,520

Loss from operations

(11,613)

(13,513)

(14,040)

(15,520)

Other income, net

98

145

215

218

Net loss applicable to common stockholders

$

(11,515)

$

(13,368)

$

(13,825)

$

(15,302)

Net loss per share applicable to common stockholders - basic and diluted

$

(0.49)

$

(0.52)

$

(0.53)

$

(0.58)

Weighted-average number of common shares used in net loss per share applicable to common stockholders - basic and diluted

23,393,448

25,584,147

26,259,216

26,316,550

Three Months Ended

March 31, 2016

June 30, 2016

September 30, 2016

December 31, 2016

Revenue

$

 —

$

 —

$

 —

$

317

Operating expenses:

Research and development

8,265

9,525

11,584

8,443

General and administrative

2,371

2,540

2,633

2,919

Total operating expenses

10,636

12,065

14,217

11,362

Loss from operations

(10,636)

(12,065)

(14,217)

(11,045)

Other income, net

48

44

48

80

Net loss

$

(10,588)

$

(12,021)

$

(14,169)

$

(10,965)

Accrued dividends on preferred stock

(1,737)

(1,823)

(121)

 —

Net loss applicable to common stockholders

$

(12,325)

$

(13,844)

$

(14,290)

$

(10,965)

Net loss per share applicable to common stockholders - basic and diluted

$

(5.15)

$

(5.42)

$

(0.65)

$

(0.47)

Weighted-average number of common shares used in net loss per share applicable to common stockholders - basic and diluted

2,394,470

2,553,146

22,012,743

23,374,734