Summary of Significant Accounting Policies (Tables)
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6 Months Ended |
Jun. 30, 2019 |
|---|
| Accounting Policies [Abstract] |
|
| Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis |
The following tables present the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis using the above input categories (in thousands):
|
|
|
As of June 30, 2019
|
|
|
|
|
Level 1
|
|
|
Level 2
|
|
|
Level 3
|
|
|
Total Fair Value
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
24,168
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
24,168
|
|
|
Total cash equivalents
|
|
|
24,168
|
|
|
|
-
|
|
|
|
-
|
|
|
|
24,168
|
|
|
Marketable securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
57,509
|
|
|
|
-
|
|
|
|
57,509
|
|
|
U.S. and foreign corporate debt securities
|
|
|
-
|
|
|
|
60,011
|
|
|
|
-
|
|
|
|
60,011
|
|
|
Asset-backed securities
|
|
|
-
|
|
|
|
47,340
|
|
|
|
-
|
|
|
|
47,340
|
|
|
U.S. treasury securities
|
|
|
-
|
|
|
|
48,266
|
|
|
|
-
|
|
|
|
48,266
|
|
|
Total marketable securities
|
|
|
-
|
|
|
|
213,126
|
|
|
|
-
|
|
|
|
213,126
|
|
|
Total assets measured at fair value
|
|
$
|
24,168
|
|
|
$
|
213,126
|
|
|
$
|
-
|
|
|
$
|
237,294
|
|
|
|
|
As of December 31, 2018
|
|
|
|
|
Level 1
|
|
|
Level 2
|
|
|
Level 3
|
|
|
Total Fair Value
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
39,481
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
39,481
|
|
|
U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
6,469
|
|
|
|
-
|
|
|
|
6,469
|
|
|
Total cash equivalents
|
|
|
39,481
|
|
|
|
6,469
|
|
|
|
-
|
|
|
|
45,950
|
|
|
Marketable securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
51,627
|
|
|
|
-
|
|
|
|
51,627
|
|
|
U.S. and foreign corporate debt securities
|
|
|
-
|
|
|
|
34,634
|
|
|
|
-
|
|
|
|
34,634
|
|
|
Asset-backed securities
|
|
|
-
|
|
|
|
25,472
|
|
|
|
-
|
|
|
|
25,472
|
|
|
U.S. treasury securities
|
|
|
-
|
|
|
|
17,936
|
|
|
|
-
|
|
|
|
17,936
|
|
|
Total marketable securities
|
|
|
-
|
|
|
|
129,669
|
|
|
|
-
|
|
|
|
129,669
|
|
|
Total assets measured at fair value
|
|
$
|
39,481
|
|
|
$
|
136,138
|
|
|
$
|
-
|
|
|
$
|
175,619
|
|
|
| Schedule of Changes in Fair Value of Liabilities |
The following table sets forth a summary of the changes in the fair value of the Company’s liabilities measured using Level 3 inputs (in thousands):
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|
|
For the Six
|
|
|
|
|
Months Ended June 30,
|
|
|
|
|
2019
|
|
|
2018
|
|
|
Balance, beginning of period
|
|
$
|
-
|
|
|
$
|
6,091
|
|
|
Change in fair value
|
|
|
-
|
|
|
|
4,741
|
|
|
Settlement of financial instruments
|
|
|
-
|
|
|
|
(5,200
|
)
|
|
Balance, end of period
|
|
$
|
-
|
|
|
$
|
5,632
|
|
|
| Schedule of Amortized Cost, Unrealized Gain and Loss, and Fair Value of Available for Sale Marketable Securities |
The following tables summarize amortized cost, unrealized gain and loss, and fair value of the Company’s available for sale marketable securities (in thousands):
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|
|
|
|
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Gross
|
|
|
Gross
|
|
|
|
|
|
|
|
|
Amortized
|
|
|
Unrealized
|
|
|
Unrealized
|
|
|
Total
|
|
|
|
|
Cost
|
|
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Gains
|
|
|
Losses
|
|
|
Fair Value
|
|
|
As of June 30, 2019:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
$
|
57,509
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
57,509
|
|
|
U.S. and foreign corporate debt securities
|
|
|
59,895
|
|
|
|
116
|
|
|
|
-
|
|
|
|
60,011
|
|
|
Asset-backed securities
|
|
|
47,282
|
|
|
|
59
|
|
|
|
(1
|
)
|
|
|
47,340
|
|
|
U.S. treasury securities
|
|
|
48,212
|
|
|
|
54
|
|
|
|
-
|
|
|
|
48,266
|
|
|
Total marketable securities
|
|
$
|
212,898
|
|
|
$
|
229
|
|
|
$
|
(1
|
)
|
|
$
|
213,126
|
|
|
|
|
|
|
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|
Gross
|
|
|
Gross
|
|
|
|
|
|
|
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|
Amortized
|
|
|
Unrealized
|
|
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Unrealized
|
|
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Total
|
|
|
|
|
Cost
|
|
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Gains
|
|
|
Losses
|
|
|
Fair Value
|
|
|
As of December 31, 2018:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
$
|
51,627
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
51,627
|
|
|
U.S. and foreign corporate debt securities
|
|
|
34,668
|
|
|
|
-
|
|
|
|
(34
|
)
|
|
|
34,634
|
|
|
Asset-backed securities
|
|
|
25,494
|
|
|
|
-
|
|
|
|
(22
|
)
|
|
|
25,472
|
|
|
U.S. treasury securities
|
|
|
17,938
|
|
|
|
-
|
|
|
|
(2
|
)
|
|
|
17,936
|
|
|
Total marketable securities
|
|
$
|
129,727
|
|
|
$
|
-
|
|
|
$
|
(58
|
)
|
|
$
|
129,669
|
|
|
| Computation of Basic and Diluted Net Loss per Share |
The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts):
|
|
|
Three Months Ended
|
|
|
Six Months Ended
|
|
|
|
|
June 30,
|
|
|
June 30,
|
|
|
|
|
2019
|
|
|
2018
|
|
|
2019
|
|
|
2018
|
|
|
Numerator:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Net loss allocated to common stock-basic
|
|
$
|
(24,038
|
)
|
|
$
|
(17,531
|
)
|
|
$
|
(47,113
|
)
|
|
$
|
(34,536
|
)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Adjustments for revaluation and
extinguishment of common stock
warrants
|
|
|
-
|
|
|
|
(198
|
)
|
|
|
-
|
|
|
|
-
|
|
|
Net loss allocated to common stock-diluted
|
|
$
|
(24,038
|
)
|
|
$
|
(17,729
|
)
|
|
$
|
(47,113
|
)
|
|
$
|
(34,536
|
)
|
|
Denominator:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Weighted average number of
common stock shares
outstanding - basic
|
|
|
68,697,735
|
|
|
|
58,833,647
|
|
|
|
65,312,988
|
|
|
|
56,307,236
|
|
|
Dilutive securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Common stock warrants
|
|
|
-
|
|
|
|
72,251
|
|
|
|
-
|
|
|
|
-
|
|
|
Weighted average number of
common stock shares
outstanding - diluted
|
|
|
68,697,735
|
|
|
|
58,905,898
|
|
|
|
65,312,988
|
|
|
|
56,307,236
|
|
|
Net loss per share - basic:
|
|
$
|
(0.35
|
)
|
|
$
|
(0.30
|
)
|
|
$
|
(0.72
|
)
|
|
$
|
(0.61
|
)
|
|
Net loss per share - diluted:
|
|
$
|
(0.35
|
)
|
|
$
|
(0.30
|
)
|
|
$
|
(0.72
|
)
|
|
$
|
(0.61
|
)
|
|
| Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share |
The following table shows the total outstanding securities considered anti-dilutive and therefore excluded from the computation of diluted net loss per share (in thousands):
|
|
|
Three Months Ended
|
|
|
Six Months Ended
|
|
|
|
|
June 30,
|
|
|
June 30,
|
|
|
|
|
2019
|
|
|
2018
|
|
|
2019
|
|
|
2018
|
|
|
Common stock options
|
|
|
7,530
|
|
|
|
5,279
|
|
|
|
7,530
|
|
|
|
5,279
|
|
|
Incentive awards
|
|
|
127
|
|
|
|
130
|
|
|
|
127
|
|
|
|
130
|
|
|
Common stock warrants
|
|
|
-
|
|
|
|
729
|
|
|
|
-
|
|
|
|
729
|
|
|
|
|
|
7,657
|
|
|
|
6,138
|
|
|
|
7,657
|
|
|
|
6,138
|
|
|