Going Concern	12 Months Ended
Dec. 31, 2017
Going Concern [Abstract]
Going Concern	2. Going Concern The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, which contemplate continuation of the Company as a going concern. The Company has not established a source of revenues sufficient to cover its operating costs, and as such, has been dependent on funding operations through the issuance of debt and sale of equity securities. The Company expects to incur further losses over the next several years as it develops its business. At December 31, 2017, the Company had working capital of only $13.4 million. The Company’s accumulated deficit amounted to $237.4 million and $155.7 million at December 31, 2017 and 2016, respectively. Net cash used in operating activities was $64.1 million, $53.0 million and $61.0 million for years ended December 31, 2017, 2016 and 2015. The Company must raise additional capital to fund its continued operations and remain in compliance with its debt covenants. The Company may not be successful in its efforts to raise additional funds or achieve profitable operations. Amounts raised will be used for further development of the Company’s product candidates, to provide financing for marketing and promotion, to secure additional property and equipment, and for other working capital purposes. Even if the Company is able to raise additional funds through the sale of its equity securities, or loans from financial institutions, the Company’s cash needs could be greater than anticipated in which case it could be forced to raise additional capital. In September 2017, the Company raised $80.4 million in gross proceeds ($75.1 million net of $5.3 million in underwriting fees, commissions and other offering costs and expenses) from the issuance of 26,775,000 shares of common stock and warrants to purchase 10,710,000 shares of common stock at an initial exercise price of $3.35 per share for a term of 5 years from the date of issuance at a combined price of $3.001 per share and accompanying warrant (“2017 Public Offering”). Gross proceeds of $66.8 million and the issuance of 22,275,000 shares of common stock and warrants to purchase 8,910,000 shares of common stock closed in September 2017 and the remaining $13.6 million of gross proceeds and the issuance of 4,500,000 shares of common stock and warrants to purchase 1,800,000 shares of common stock closed in October 2017. In March 2017, the Company raised $22.7 million in gross proceeds ($20.9 million net of $1.8 million in placement agent fees and other offering costs and expenses) from the issuance of 6,767,855 shares of common stock, at a price of $3.36 per share, and warrants to purchase 2,707,138 shares of common stock at an initial exercise price of $4.50 per share for a term of 13 months from the date of issuance (“2017 Private Placement”). At the present time, the Company has no commitments for any additional financing, and there can be no assurance that, if needed, additional capital will be available to the Company on commercially acceptable terms or at all. If the Company cannot obtain the needed capital, it may not be able to become profitable and may have to curtail or cease its operations. These and other factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments or classifications that may result from the possible inability of the Company to continue as a going concern.

2. Going Concern

The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, which contemplate continuation of the Company as a going concern. The Company has not established a source of revenues sufficient to cover its operating costs, and as such, has been dependent on funding operations through the issuance of debt and sale of equity securities. The Company expects to incur further losses over the next several years as it develops its business.

At December 31, 2017, the Company had working capital of only $13.4 million. The Company’s accumulated deficit amounted to $237.4 million and $155.7 million at December 31, 2017 and 2016, respectively. Net cash used in operating activities was $64.1 million, $53.0 million and $61.0 million for years ended December 31, 2017, 2016 and 2015. The Company must raise additional capital to fund its continued operations and remain in compliance with its debt covenants. The Company may not be successful in its efforts to raise additional funds or achieve profitable operations. Amounts raised will be used for further development of the Company’s product candidates, to provide financing for marketing and promotion, to secure additional property and equipment, and for other working capital purposes. Even if the Company is able to raise additional funds through the sale of its equity securities, or loans from financial institutions, the Company’s cash needs could be greater than anticipated in which case it could be forced to raise additional capital.

In September 2017, the Company raised $80.4 million in gross proceeds ($75.1 million net of $5.3 million in underwriting fees, commissions and other offering costs and expenses) from the issuance of 26,775,000 shares of common stock and warrants to purchase 10,710,000 shares of common stock at an initial exercise price of $3.35 per share for a term of 5 years from the date of issuance at a combined price of $3.001 per share and accompanying warrant (“2017 Public Offering”). Gross proceeds of $66.8 million and the issuance of 22,275,000 shares of common stock and warrants to purchase 8,910,000 shares of common stock closed in September 2017 and the remaining $13.6 million of gross proceeds and the issuance of 4,500,000 shares of common stock and warrants to purchase 1,800,000 shares of common stock closed in October 2017. In March 2017, the Company raised $22.7 million in gross proceeds ($20.9 million net of $1.8 million in placement agent fees and other offering costs and expenses) from the issuance of 6,767,855 shares of common stock, at a price of $3.36 per share, and warrants to purchase 2,707,138 shares of common stock at an initial exercise price of $4.50 per share for a term of 13 months from the date of issuance (“2017 Private Placement”). At the present time, the Company has no commitments for any additional financing, and there can be no assurance that, if needed, additional capital will be available to the Company on commercially acceptable terms or at all. If the Company cannot obtain the needed capital, it may not be able to become profitable and may have to curtail or cease its operations. These and other factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments or classifications that may result from the possible inability of the Company to continue as a going concern.