Document and Entity Information
Document and Entity Information - shares | 6 Months Ended | |
Jun. 30, 2018 | Aug. 14, 2018 | |
Document And Entity Information [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Jun. 30, 2018 | |
Document Fiscal Year Focus | 2,018 | |
Document Fiscal Period Focus | Q2 | |
Trading Symbol | OXGN | |
Entity Registrant Name | MATEON THERAPEUTICS INC | |
Entity Central Index Key | 908,259 | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Smaller Reporting Accelerated Filer | |
Entity Common Stock, Shares Outstanding | 41,419,934 |
Condensed Balance Sheets
Condensed Balance Sheets - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017 |
Current assets: | ||
Cash | $ 1,966 | $ 1,115 |
Prepaid expenses and other current assets | 100 | 22 |
Total current assets | 2,066 | 1,137 |
Property and equipment, net | 2 | |
Other assets | 33 | 33 |
Total assets | 2,099 | 1,172 |
Current liabilities: | ||
Accounts payable | 1,221 | 788 |
Accrued compensation and employee benefits | 40 | 73 |
Accrued clinical trial expenses | 128 | 509 |
Other accrued liabilities | 172 | 279 |
Total current liabilities | 1,561 | 1,649 |
Commitments and contingencies | ||
Stockholders' equity/(deficit): | ||
Preferred stock, $0.01 par value, 15,000 shares authorized; No shares issued and outstanding | ||
Common stock, $0.01 par value, 150,000 and 70,000 shares authorized; 41,420 and 26,545 shares issued and outstanding at June 30, 2018 and December 31, 2017, respectively | 414 | 265 |
Additional paid-in capital | 293,835 | 291,533 |
Accumulated deficit | (293,711) | (292,275) |
Total stockholders' equity/(deficit) | 538 | (477) |
Total liabilities and stockholders' equity/(deficit) | $ 2,099 | $ 1,172 |
Condensed Balance Sheets (Paren
Condensed Balance Sheets (Parenthetical) - $ / shares | Jun. 30, 2018 | Dec. 31, 2017 |
Statement of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.01 | $ 0.01 |
Preferred stock, shares authorized | 15,000,000 | 15,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.01 | $ 0.01 |
Common stock, shares authorized | 150,000,000 | 70,000,000 |
Common stock, shares issued | 41,420,000 | 26,545,000 |
Common stock, shares outstanding | 41,420,000 | 26,545,000 |
Condensed Statements of Compreh
Condensed Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Operating expenses: | ||||
Research and development | $ 342 | $ 3,019 | $ 567 | $ 5,867 |
General and administrative | 556 | 877 | 1,126 | 1,999 |
Total operating expenses | 898 | 3,896 | 1,693 | 7,866 |
Loss from operations | (898) | (3,896) | (1,693) | (7,866) |
Gain on change in fair value of warrants | 250 | 250 | ||
Interest income | 7 | 12 | 8 | 26 |
Other expense | (1) | (1) | (2) | |
Net loss and comprehensive loss | $ (642) | $ (3,884) | $ (1,436) | $ (7,842) |
Basic and diluted net loss per share attributable to common stock | $ (0.02) | $ (0.15) | $ (0.04) | $ (0.30) |
Weighted-average number of common shares outstanding | 39,409 | 26,545 | 33,012 | 26,545 |
Condensed Statements of Cash Fl
Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Operating activities: | ||
Net loss | $ (1,436) | $ (7,842) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Gain on change in fair value of warrants | (250) | |
Depreciation | 2 | 5 |
Stock-based compensation | 343 | 446 |
Changes in operating assets and liabilities: | ||
Prepaid expenses and other current assets | (78) | 537 |
Accounts payable and accrued expenses | (88) | (189) |
Net cash used in operating activities | (1,507) | (7,043) |
Investing activities: | ||
Sale of short-term investments | 8,512 | |
Financing activities: | ||
Proceeds from issuance of common stock and warrants, net of issuance costs | 2,358 | |
Increase in cash and cash equivalents | 851 | 1,469 |
Cash and cash equivalents at beginning of period | 1,115 | 3,535 |
Cash and cash equivalents at end of period | $ 1,966 | $ 5,004 |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 6 Months Ended |
Jun. 30, 2018 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | 1. Summary of Significant Accounting Policies Description of Business Mateon Therapeutics, Inc. (“Mateon” or the “Company”) is a clinical-stage biopharmaceutical company developing drugs for the treatment of orphan oncology indications, with a program in acute myeloid leukemia (“AML”) and myelodysplastic syndromes (“MDS”) and a program in immuno-oncology. Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q Regulation S-X. The balance sheet at December 31, 2017 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements. For further information, refer to the financial statements and footnotes thereto included in the Annual Report on Form 10-K Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Cash Equivalents Highly liquid investments with original maturities of three months or less at the date of purchase are considered to be cash equivalents. Cash equivalents are stated at fair value. Derivative Financial Instruments Indexed to the Company’s Common Stock The Company has generally issued derivative financial instruments, such as warrants, in connection with its equity offerings. The Company evaluates the terms of these derivative financial instruments in order to determine their accounting treatment in the Company’s financial statements. Key considerations include whether the financial instruments are freestanding and whether they contain conditional obligations. If the warrants are freestanding, do not contain conditional obligations and meet other classification criteria, the Company accounts for the warrants as an equity instrument. If the warrants are freestanding but contain conditional obligations, then the Company accounts for the warrants as a liability until the conditional obligations are met or are no longer relevant. For financial instruments which are accounted for as a liability, the Company reports changes in their estimated fair value as a gain or loss in the Company’s Statement of Comprehensive Loss. Going Concern Evaluation The Company has experienced net losses every year since inception and, as of June 30, 2018, had an accumulated deficit of approximately $294 million. The Company has no source of revenue and does not expect to receive any product revenue in the near future. The Company expects to incur significant additional operating losses over at least the next several years, principally as a result of the Company’s continuing clinical trials for its investigational drugs. The principal source of the Company’s working capital to date has been the proceeds from the sale of equity. As of June 30, 2018, the Company had $2.0 million in cash and current liabilities of $1.6 million. Based on the Company’s planned operations, the Company’s management expects its cash to support its operations into the fourth quarter of 2018. Prior to this time, the Company will need to secure additional funding or could be forced to curtail or terminate operations. Because the Company does not currently have a guaranteed source of working capital that will sustain planned operations past the fourth quarter of 2018, Management has determined that there is substantial doubt about the Company’s ability to continue as a going concern. The Company will need to raise capital in order to fund its planned operations beyond this time. If the Company is unable to access additional funds when needed, it may not be able to continue the development of its investigational drugs and the Company could be required to delay, scale back or eliminate some or all of its development programs and other operations. Any additional equity financing, if available to the Company, may not be available on favorable terms, would most likely be dilutive to its current stockholders and debt financing, if available, may involve restrictive covenants. If the Company accesses funds through collaborative or licensing arrangements, it may be required to relinquish rights to some of its technologies or product candidates that it would otherwise seek to develop or commercialize on its own, on terms that are not favorable to the Company. The Company’s ability to access capital when needed is not assured and, if not achieved on a timely basis, will materially harm its business, financial condition and results of operations. Recent Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-2, right-of-use In August 2016, The FASB issued ASU No. 2016-15 |
Stockholders' Equity
Stockholders' Equity | 6 Months Ended |
Jun. 30, 2018 | |
Equity Abstract | |
Stockholders' Equity | 2. Stockholders’ Equity April 2018 Private Placement In April 2018, the Company entered into a private placement transaction, raising net proceeds of approximately $2.4 million from the sale of 14,875,000 shares of common stock and warrants to purchase 14,875,000 shares of common stock. The purchase price of the common stock was $0.20 per share and the exercise price of the warrants is $0.40 per share. The warrants expire two years from the date they initially became exercisable. In connection with the private placement transaction, the Company also issued 1,487,500 warrants to the placement agent. The placement agent warrants have an exercise price of $0.20 per share and expire five years from the date of issuance. The warrants consist of 7,437,500 Series A warrants (the “Series A Warrants”) and 7,437,500 Series B warrants (the “Series B Warrants”). The exercise price of all warrants is payable in cash and there are no cashless exercise provisions. The Series A Warrants were immediately exercisable upon issuance and expire on April 12, 2020. The Company has accounted for the Series A Warrants as an equity instrument from the date of issuance. When the Company completed the private placement transaction, the exercisability and expiration of the Series B Warrants were dependent on the Company’s receipt of stockholder approval for an increase in the number of authorized shares of the Company’s common stock. Accordingly, on the date of issuance, the Company accounted for the Series B Warrants as a liability, utilizing the Black-Scholes option pricing model to determine the fair value of these derivative financial instruments based on the following key measurements and assumptions: $0.26 per share stock price; $0.40 per share exercise price; 2.2 year term to maturity; 2.37% risk-free interest rate and 100.9% annualized volatility, resulting in an estimated fair value of the warrant liability of $886,000. On June 20, 2018, the Company’s stockholders approved an increase in the number of authorized shares of common stock, satisfying the conditional obligation of the Series B Warrants. The Series B Warrants became exercisable on June 20, 2018 and expire on June 20, 2020. Following the stockholder approval, the Company determined that liability accounting was no longer appropriate and that equity accounting was appropriate for the Series B Warrants. The Company utilized the Black-Scholes option pricing model to determine the Series B Warrants’ fair value as of June 20, 2018, based on the following key measurements and assumptions: $0.22 per share stock price; $0.40 per share exercise price; 2.0 year term to maturity; 2.56% risk-free interest rate and 100.0% annualized volatility, resulting in an estimated fair value of the warrant liability of $636,000. The decrease in the fair value of the Series B Warrants from the date of issuance through the satisfaction of the conditional criteria has been classified as a “Gain on change in fair value of warrants” in the Statement of Comprehensive Loss. Outstanding Warrants to Purchase Common Stock The following is a summary of the Company’s outstanding common stock warrants: Exercise June 30, 2018 December 31, 2017 Expiration Date Price (in thousands) 04/16/18 $ 3.40 — 1,460 09/23/18 $ 2.80 147 147 02/11/19 $ 2.56 293 293 02/18/19 $ 2.75 1,872 1,872 08/28/19 $ 2.90 2,700 2,700 03/20/20 $ 2.13 234 234 03/25/20 $ 1.71 2,920 2,920 04/12/20 $ 0.40 7,437 — 06/20/20 $ 0.40 7,437 — 04/30/23 $ 0.20 1,488 — Total Warrants Outstanding 24,528 9,626 Equity Incentive Plans The following is a summary of the Company’s stock option activity under its equity incentive plans: Options Options Weighted Weighted Aggregate (in thousands) (years) (in thousands) Balance at December 31, 2017 1,846 4,880 $ 1.05 7.63 $ — Options authorized 2,524 — Options granted (3,033 ) 3,033 $ 0.22 Options forfeited 594 (594 ) $ 0.69 Balance at June 30, 2018 1,931 7,319 $ 0.73 7.68 $ — Vested and exercisable at June 30, 2018 2,757 $ 0.99 6.65 $ — Vested and expected to vest at June 30, 2018 6,291 $ 0.62 7.62 $ — Unvested at June 30, 2018 4,562 $ 0.58 As of June 30, 2018, there was approximately $0.9 million of unrecognized compensation cost related to stock option awards that is expected to be recognized as expense over a weighted average period of approximately 1.5 years. The fair value for stock options granted is estimated at the date of grant using the Black-Scholes option pricing model. The Company used the following weighted average assumptions to estimate the fair value of the stock options. Six months ended June 30, 2018 2017 Risk-free interest rate 2.8 % 2.0 % Expected life (years) 5.2 6.0 Expected volatility 88 % 88 % Dividend yield 0 % 0 % |
Net Loss Per Share
Net Loss Per Share | 6 Months Ended |
Jun. 30, 2018 | |
Earnings Per Share [Abstract] | |
Net Loss Per Share | 3. Net Loss Per Share Basic and diluted net loss per share was calculated by dividing the net loss per share attributed to the Company’s common shares by the weighted-average number of common shares outstanding during the period. Diluted net loss per share includes the effect of all dilutive, potentially issuable common equivalent shares as defined using the treasury stock method. All of the Company’s common stock equivalents are anti-dilutive due to the Company’s net loss position for all periods presented. Accordingly, common stock equivalents of approximately 7,319,000 stock options and 24,528,000 warrants at June 30, 2018 and 5,941,000 stock options and 9,842,000 warrants at June 30, 2017, were excluded from the calculation of weighted average shares for diluted net loss per share. |
Summary of Significant Account9
Summary of Significant Accounting Policies (Policies) | 6 Months Ended |
Jun. 30, 2018 | |
Accounting Policies [Abstract] | |
Description of Business | Description of Business Mateon Therapeutics, Inc. (“Mateon” or the “Company”) is a clinical-stage biopharmaceutical company developing drugs for the treatment of orphan oncology indications, with a program in acute myeloid leukemia (“AML”) and myelodysplastic syndromes (“MDS”) and a program in immuno-oncology. |
Basis of Presentation | Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q Regulation S-X. The balance sheet at December 31, 2017 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements. For further information, refer to the financial statements and footnotes thereto included in the Annual Report on Form 10-K |
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. |
Cash Equivalents | Cash Equivalents Highly liquid investments with original maturities of three months or less at the date of purchase are considered to be cash equivalents. Cash equivalents are stated at fair value. |
Derivative Financial Instruments Indexed to the Company's Common Stock | Derivative Financial Instruments Indexed to the Company’s Common Stock The Company has generally issued derivative financial instruments, such as warrants, in connection with its equity offerings. The Company evaluates the terms of these derivative financial instruments in order to determine their accounting treatment in the Company’s financial statements. Key considerations include whether the financial instruments are freestanding and whether they contain conditional obligations. If the warrants are freestanding, do not contain conditional obligations and meet other classification criteria, the Company accounts for the warrants as an equity instrument. If the warrants are freestanding but contain conditional obligations, then the Company accounts for the warrants as a liability until the conditional obligations are met or are no longer relevant. For financial instruments which are accounted for as a liability, the Company reports changes in their estimated fair value as a gain or loss in the Company’s Statement of Comprehensive Loss. |
Going Concern Evaluation | Going Concern Evaluation The Company has experienced net losses every year since inception and, as of June 30, 2018, had an accumulated deficit of approximately $294 million. The Company has no source of revenue and does not expect to receive any product revenue in the near future. The Company expects to incur significant additional operating losses over at least the next several years, principally as a result of the Company’s continuing clinical trials for its investigational drugs. The principal source of the Company’s working capital to date has been the proceeds from the sale of equity. As of June 30, 2018, the Company had $2.0 million in cash and current liabilities of $1.6 million. Based on the Company’s planned operations, the Company’s management expects its cash to support its operations into the fourth quarter of 2018. Prior to this time, the Company will need to secure additional funding or could be forced to curtail or terminate operations. Because the Company does not currently have a guaranteed source of working capital that will sustain planned operations past the fourth quarter of 2018, Management has determined that there is substantial doubt about the Company’s ability to continue as a going concern. The Company will need to raise capital in order to fund its planned operations beyond this time. If the Company is unable to access additional funds when needed, it may not be able to continue the development of its investigational drugs and the Company could be required to delay, scale back or eliminate some or all of its development programs and other operations. Any additional equity financing, if available to the Company, may not be available on favorable terms, would most likely be dilutive to its current stockholders and debt financing, if available, may involve restrictive covenants. If the Company accesses funds through collaborative or licensing arrangements, it may be required to relinquish rights to some of its technologies or product candidates that it would otherwise seek to develop or commercialize on its own, on terms that are not favorable to the Company. The Company’s ability to access capital when needed is not assured and, if not achieved on a timely basis, will materially harm its business, financial condition and results of operations. |
Recent Accounting Pronouncements | Recent Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-2, right-of-use In August 2016, The FASB issued ASU No. 2016-15 |
Stockholders' Equity (Tables)
Stockholders' Equity (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Equity Abstract | |
Summary of the Company's Outstanding Common Stock Warrants | The following is a summary of the Company’s outstanding common stock warrants: Exercise June 30, 2018 December 31, 2017 Expiration Date Price (in thousands) 04/16/18 $ 3.40 — 1,460 09/23/18 $ 2.80 147 147 02/11/19 $ 2.56 293 293 02/18/19 $ 2.75 1,872 1,872 08/28/19 $ 2.90 2,700 2,700 03/20/20 $ 2.13 234 234 03/25/20 $ 1.71 2,920 2,920 04/12/20 $ 0.40 7,437 — 06/20/20 $ 0.40 7,437 — 04/30/23 $ 0.20 1,488 — Total Warrants Outstanding 24,528 9,626 |
Summary of the Company's Stock Option Activity under Equity Incentive Plans | The following is a summary of the Company’s stock option activity under its equity incentive plans: Options Options Weighted Weighted Aggregate (in thousands) (years) (in thousands) Balance at December 31, 2017 1,846 4,880 $ 1.05 7.63 $ — Options authorized 2,524 — Options granted (3,033 ) 3,033 $ 0.22 Options forfeited 594 (594 ) $ 0.69 Balance at June 30, 2018 1,931 7,319 $ 0.73 7.68 $ — Vested and exercisable at June 30, 2018 2,757 $ 0.99 6.65 $ — Vested and expected to vest at June 30, 2018 6,291 $ 0.62 7.62 $ — Unvested at June 30, 2018 4,562 $ 0.58 |
Weighted-Average Assumptions | The fair value for stock options granted is estimated at the date of grant using the Black-Scholes option pricing model. The Company used the following weighted average assumptions to estimate the fair value of the stock options. Six months ended June 30, 2018 2017 Risk-free interest rate 2.8 % 2.0 % Expected life (years) 5.2 6.0 Expected volatility 88 % 88 % Dividend yield 0 % 0 % |
Summary of Significant Accoun11
Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands | 6 Months Ended | |||
Jun. 30, 2018 | Dec. 31, 2017 | Jun. 30, 2017 | Dec. 31, 2016 | |
Accounting Policies [Abstract] | ||||
Cash equivalents maturities, term | three months or less | |||
Accumulated deficit | $ (293,711) | $ (292,275) | ||
Cash | 1,966 | 1,115 | $ 5,004 | $ 3,535 |
Current liabilities | $ 1,561 | $ 1,649 | ||
Substantial doubt about going concern, management's evaluation | Company's management expects its cash to support its operations into the fourth quarter of 2018. Prior to this time, the Company will need to secure additional funding or could be forced to curtail or terminate operations. Because the Company does not currently have a guaranteed source of working capital that will sustain planned operations past the fourth quarter of 2018, Management has determined that there is substantial doubt about the Company's ability to continue as a going concern. |
Stockholders' Equity - Addition
Stockholders' Equity - Additional Information (Detail) - USD ($) | Jun. 20, 2018 | Apr. 30, 2018 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017 |
Stockholders Equity [Line Items] | |||||
Number of warrants outstanding | 24,528,000 | 9,626,000 | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, expected term | 5 years 2 months 12 days | 6 years | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, risk free interest rate | 2.80% | 2.00% | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, expected volatility rate | 88.00% | 88.00% | |||
Weighted average period for recognizing unrecognized compensation cost | 1 year 6 months | ||||
Unrecognized compensation cost related to stock option awards | $ 900,000 | ||||
Private Placement Series A [Member] | |||||
Stockholders Equity [Line Items] | |||||
Warrants exercise price | $ 0.40 | ||||
Number of warrants outstanding | 7,437,500 | 7,437,000 | |||
Warrant expiration date | Apr. 12, 2020 | ||||
Private Placement Series B Warrants [Member] | |||||
Stockholders Equity [Line Items] | |||||
Purchase price of common stock per share | $ 0.22 | $ 0.26 | |||
Warrants exercise price | $ 0.40 | $ 0.40 | $ 0.40 | ||
Number of warrants outstanding | 7,437,500 | 7,437,000 | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, expected term | 2 years | 2 years 2 months 12 days | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, risk free interest rate | 2.56% | 2.37% | |||
Share-based compensation arrangement by share-based payment award, fair value assumptions, expected volatility rate | 100.00% | 100.90% | |||
Warrant liability | $ 636,000 | $ 886,000 | |||
Warrants exercisable period | Jun. 20, 2018 | ||||
Warrants expiration period | Jun. 20, 2020 | ||||
2018 Private Placement [Member] | |||||
Stockholders Equity [Line Items] | |||||
Net proceeds from private placement transaction | $ 2,400,000 | ||||
Sale of common stock shares | 14,875,000 | ||||
Warrants to purchase shares of common stock | 14,875,000 | ||||
Purchase price of common stock per share | $ 0.20 | ||||
Warrants exercise price | $ 0.40 | ||||
Warrants expiration period | 2 years | ||||
2018 Private Placement [Member] | Placement Agent [Member] | |||||
Stockholders Equity [Line Items] | |||||
Warrants to purchase shares of common stock | 1,487,500 | ||||
Warrants exercise price | $ 0.20 | ||||
Warrants expiration period | 5 years |
Stockholders' Equity - Summary
Stockholders' Equity - Summary of the Company's Outstanding Common Stock Warrants (Detail) - $ / shares | 6 Months Ended | |||
Jun. 30, 2018 | Jun. 20, 2018 | Apr. 30, 2018 | Dec. 31, 2017 | |
Class of Warrant or Right [Line Items] | ||||
Number of warrants outstanding | 24,528,000 | 9,626,000 | ||
1st Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Apr. 16, 2018 | |||
Exercise Price | $ 3.40 | |||
Number of warrants outstanding | 1,460,000 | |||
2nd Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Sep. 23, 2018 | |||
Exercise Price | $ 2.80 | |||
Number of warrants outstanding | 147,000 | 147,000 | ||
3rd Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Feb. 11, 2019 | |||
Exercise Price | $ 2.56 | |||
Number of warrants outstanding | 293,000 | 293,000 | ||
4th Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Feb. 18, 2019 | |||
Exercise Price | $ 2.75 | |||
Number of warrants outstanding | 1,872,000 | 1,872,000 | ||
5th Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Aug. 28, 2019 | |||
Exercise Price | $ 2.90 | |||
Number of warrants outstanding | 2,700,000 | 2,700,000 | ||
6th Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Mar. 20, 2020 | |||
Exercise Price | $ 2.13 | |||
Number of warrants outstanding | 234,000 | 234,000 | ||
7th Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Mar. 25, 2020 | |||
Exercise Price | $ 1.71 | |||
Number of warrants outstanding | 2,920,000 | 2,920,000 | ||
Private Placement Series A [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Apr. 12, 2020 | |||
Exercise Price | $ 0.40 | |||
Number of warrants outstanding | 7,437,000 | 7,437,500 | ||
Private Placement Series B Warrants [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Jun. 20, 2020 | |||
Exercise Price | $ 0.40 | $ 0.40 | $ 0.40 | |
Number of warrants outstanding | 7,437,000 | 7,437,500 | ||
10th Private Placement [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Expiration Date | Apr. 30, 2023 | |||
Exercise Price | $ 0.20 | |||
Number of warrants outstanding | 1,488,000 |
Stockholders' Equity - Summar14
Stockholders' Equity - Summary of the Company's Stock Option Activity under Equity Incentive Plans (Detail) $ / shares in Units, shares in Thousands, $ in Thousands | 6 Months Ended |
Jun. 30, 2018USD ($)$ / sharesshares | |
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |
Options Available for Grant, Beginning Balance | 1,846 |
Options Available for Grant, Options authorized | 2,524 |
Options Available for Grant, Options granted | (3,033) |
Options Available for Grant, Options forfeited | 594 |
Options Available for Grant, Ending Balance | 1,931 |
Options Outstanding, Beginning Balance | 4,880 |
Options Outstanding, Options granted | 3,033 |
Options Outstanding, Options forfeited | (594) |
Options Outstanding, Ending Balance | 7,319 |
Options Outstanding, Vested and exercisable | 2,757 |
Options Outstanding, Vested and expected to vest, Ending Balance | 6,291 |
Options Outstanding, Unvested | 4,562 |
Weighted Average Exercise Price, Beginning Balance | $ / shares | $ 1.05 |
Weighted Average Exercise Price, Options granted | $ / shares | 0.22 |
Weighted Average Exercise Price, Options forfeited | $ / shares | 0.69 |
Weighted Average Exercise Price, Ending Balance | $ / shares | 0.73 |
Weighted Average Exercise Price, Vested and exercisable | $ / shares | 0.99 |
Weighted Average Exercise Price, Vested and expected to vest, Ending Balance | $ / shares | 0.62 |
Weighted Average Exercise Price, Unvested | $ / shares | $ 0.58 |
Weighted Average Remaining Contractual Life, Beginning Balance | 7 years 7 months 17 days |
Weighted Average Remaining Contractual Life, Ending Balance | 7 years 8 months 4 days |
Weighted Average Remaining Contractual Life, Vested and exercisable | 6 years 7 months 24 days |
Weighted Average Remaining Contractual Life, Vested and expected to vest, Ending Balance | 7 years 7 months 13 days |
Aggregate Intrinsic Value | $ | $ 0 |
Aggregate Intrinsic Value, Vested and exercisable | $ | 0 |
Aggregate Intrinsic Value, Vested and expected to vest, Ending Balance | $ | $ 0 |
Stockholders' Equity - Weighted
Stockholders' Equity - Weighted-Average Assumptions (Detail) | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | ||
Risk-free interest rate | 2.80% | 2.00% |
Expected life (years) | 5 years 2 months 12 days | 6 years |
Expected volatility | 88.00% | 88.00% |
Dividend yield | 0.00% | 0.00% |
Net Loss Per Share - Additional
Net Loss Per Share - Additional Information (Detail) - shares shares in Thousands | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Stock Option [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Common stock excluded from the calculation of weighted average shares for diluted net loss per share | 7,319 | 5,941 |
Warrants [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Common stock excluded from the calculation of weighted average shares for diluted net loss per share | 24,528 | 9,842 |