Fair Value Measurements (Tables)
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9 Months Ended |
Sep. 30, 2018 |
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| Information about Company's Financial Assets and Liabilities Measured at Fair Value on Recurring Basis |
The following fair value hierarchy table presents information about
the Company’s financial assets and liabilities measured at
fair value on a recurring basis as of September 30, 2018 and
December 31, 2017:
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Fair Value Measurement as of
September 30, 2018 |
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Quoted Prices
in Active
Markets for
Identical Assets
(Level 1) |
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Significant
Other
Observable
Inputs
(Level 2) |
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Significant
Unobservable
Inputs
(Level 3) |
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Cash equivalents
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$ |
10,237,703 |
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$ |
— |
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$ |
— |
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Marketable securities
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26,645,137 |
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— |
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— |
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Warrant liabilities
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— |
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— |
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35,379,814 |
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Total
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$ |
36,882,840 |
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$ |
— |
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$ |
35,379,814 |
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Fair Value Measurement as of December 31, 2017
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Quoted Prices
in Active
Markets for
Identical Assets
(Level 1) |
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Significant
Other
Observable
Inputs
(Level 2) |
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Significant
Unobservable
Inputs
(Level 3) |
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Cash equivalents
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$ |
5,949,477 |
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$ |
— |
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$ |
— |
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Marketable securities
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39,858,864 |
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— |
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— |
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Warrant liabilities
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— |
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— |
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13,549,437 |
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Total
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$ |
45,808,341 |
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$ |
— |
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$ |
13,549,437 |
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| Reconciliation of Company's Financial Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3) |
The following tables present a reconciliation of the
Company’s financial liabilities measured at fair value on a
recurring basis using significant unobservable inputs (Level 3) for
the three and nine months ended September 30, 2018 and
2017:
Warrant liabilities
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Three Months Ended
September 30, |
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Nine Months Ended
September 30, |
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2018 |
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2017 |
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2018 |
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2017 |
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Balance at beginning of period
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$ |
38,626,579 |
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$ |
9,581,916 |
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$ |
13,549,437 |
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$ |
12,698,980 |
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Issuance of warrants
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— |
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12,383,435 |
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— |
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12,383,435 |
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(Decrease) increase in fair value (1)
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(3,246,765 |
) |
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(5,941,144 |
) |
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21,830,377 |
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(9,058,208 |
) |
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Balance at end of period
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$ |
35,379,814 |
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$ |
16,024,207 |
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$ |
35,379,814 |
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$ |
16,024,207 |
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| (1) |
The change in fair values of the warrant liabilities
is recorded in other income (expense) in the consolidated statement
of operations.
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| Representative's Warrant [Member] |
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| Assumption Used to Determine Fair Value of Warrant Liability |
The following assumptions were used in a Black- Scholes
option-pricing model to determine the fair value of the warrant
liability:
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As of
September 30,
2018 |
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As of
December 31,
2017 |
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Expected volatility
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64.0 |
% |
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88.1 |
% |
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Remaining contractual term (in years)
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0.92 |
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1.67 |
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Risk-free interest rate
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2.59 |
% |
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1.89 |
% |
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Expected dividend yield
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— |
% |
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— |
% |
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| 2016 Warrants [Member] |
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| Assumption Used to Determine Fair Value of Warrant Liability |
The following assumptions were used in a Black-Scholes
option-pricing model to determine the fair value of the warrant
liability:
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As of
September 30,
2018 |
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As of
December 31,
2017 |
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Expected volatility
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82.6 |
% |
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80.3 |
% |
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Remaining contractual term (in years)
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2.83 |
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3.58 |
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Risk-free interest rate
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2.88 |
% |
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2.09 |
% |
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Expected dividend yield
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— |
% |
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— |
% |
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| 2017 Warrants [Member] |
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| Assumption Used to Determine Fair Value of Warrant Liability |
The following assumptions were used in a Black-Scholes
option-pricing model to determine the fair value of the warrant
liability:
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As of
September 30,
2018 |
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As of
December 31,
2017 |
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Expected volatility
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87.0 |
% |
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81.5 |
% |
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Remaining contractual term (in years)
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3.83 |
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4.58 |
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Risk-free interest rate
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2.91 |
% |
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2.20 |
% |
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Expected dividend yield
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— |
% |
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— |
% |
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