Stockholders Equity Transactions Note Disclosure [Text Block] | 8. EQUITY Proposal for Reverse Stock Split On October 4, 2016, the Company issued a press release announcing that its board of directors approved a plan that includes both a reverse split of the Company’s common stock to increase its share price and a reduction in the number of authorized and outstanding shares. The Company plans to hold a special meeting on November 18, 2016 at its headquarters to obtain stockholder approval of the reverse split, proposed at a ratio of not less than 1-for-4 and not greater than 1-for-10, with the exact ratio to be set within that range by the Company’s board of directors before December 31, 2016, and to reduce the total authorized shares of the Company’s common stock by two times (2x) the reverse split ratio. June 2016 Financing Common Stock On June 28, 2016, the Company closed an underwritten public offering of 40,250,000 shares of its common stock at a price to the public of $0.80 per share for gross proceeds of $32.2 million. The shares included 5,250,000 shares of common stock sold pursuant to the option granted by the Company to the underwriters to purchase additional shares, which was exercised in full. Series D Convertible Preferred Stock In addition, on June 28, 2016, the Company closed a registered direct offering of 17,250 shares of its Series D Convertible Preferred Stock at a price of $800.00 per share directly to affiliates of BVF Partners L.P. (BVF), which are existing stockholders and affiliates of a member of the board of directors, for gross proceeds of $13.8 million. The Company designated 17,250 shares of its authorized and unissued preferred stock as Series D convertible preferred stock and filed a Certificate of Designation of Preferences, Rights and Limitations of Series D Convertible Preferred Stock with the Delaware Secretary of State. Each share of Series D Convertible Preferred Stock is convertible into 1,000 shares of the Company’s Common Stock at any time at the holder’s option. The holder, however, will be prohibited from converting Series D Convertible Preferred Stock into shares of common stock if, as a result of such conversion, the holder, together with its affiliates, would own more than 19.99% of the shares of the Company’s Common Stock then issued and outstanding, which percentage may change at the holders’ election to any other number less than or equal to 19.99% upon 61 days’ notice to the Company. In the event of the Company’s liquidation, dissolution, or winding up, holders of Series D Convertible Preferred Stock will receive a payment equal to $0.0001 per share of Series D Convertible Preferred Stock before any proceeds are distributed to the holders of common stock, after any proceeds are distributed to the holder of the Company’s Class UA Preferred Stock and on parity with any distributions to the holders of the Company’s Series A Convertible Preferred Stock, Series B Convertible Preferred Stock and Series C Convertible Preferred Stock. Shares of Series D Convertible Preferred Stock will generally have no voting rights, except as required by law and except that the consent of holders of a majority of the outstanding Series D Convertible Preferred Stock will be required to amend the terms of the Series D Convertible Preferred Stock. Shares of Series D Convertible Preferred Stock will not be entitled to receive any dividends, unless and until specifically declared by the Company’s board of directors, and will rank: ● senior to all common stock; ● senior to any class or series of capital stock created that specifically ranks by its terms junior to the Series D convertible preferred stock; ● on parity with the Company’s Series A convertible preferred stock, Series B Convertible Preferred Stock and Series C convertible preferred stock, and any class or series of capital stock created that specifically ranks by its terms on parity with the Series D convertible preferred stock; and ● junior to the Company’s Class UA preferred stock and any class or series of capital stock created that specifically ranks by its terms senior to the Series D convertible preferred stock; in each case, as to distributions of assets upon the Company’s liquidation, dissolution or winding up, whether voluntarily or involuntarily. Aggregate gross proceeds from the June 2016 offerings were $46.0 million. Aggregate net proceeds from the June 2016 offerings, after underwriting discounts, commissions and other expenses of $2.7 million, were approximately $43.3 million. Beneficial Conversion Feature A beneficial conversion feature exists when the effective conversion price of a convertible security is less than the market price per share on the commitment date, creating a discount. The value of the discount is determined by the difference between the market price and the conversion price multiplied by the potential conversion shares purchased. The discount is recognized as a non-cash deemed dividend from the date of issuance to the earliest conversion date. The Company recognized a beneficial conversion feature in the amount of $2.6 million, calculated as the number of potential conversion shares multiplied by the excess of the market price of its common stock over the price per conversion share of the Series D convertible preferred stock on the commitment date. The Company immediately accreted $1.6 million of the $2.6 million beneficial conversion feature, representing approximately 60% of the Series D convertible preferred stock that could be converted at that time, upon issuance during the second quarter of 2016. The Company accreted the remaining $1.0 million beneficial conversion feature, representing 40% of the Series D convertible preferred stock that could not be converted upon issuance due to certain contractual limitations, from the issuance date to the earliest conversion date, which fell within the third quarter of 2016. The non-cash deemed dividends of $1.0 million and $2.6 million were recorded in additional paid-in capital and as a deemed dividend on the Series D convertible preferred stock, and were used in determining the net loss applicable to common stockholders in the consolidated statement of operations for the three and nine months ended September 30, 2016, respectively. “At-the-Market” Equity Offering Program On June 2, 2016, the Company entered into a Sales Agreement (the Sales Agreement) with Cowen and Company, LLC (Cowen) to sell shares of the Company’s common stock, par value $0.0001 per share, having aggregate sales proceeds of up to $50,000,000, from time to time, through an “at the market” equity offering program under which Cowen will act as sales agent. Under the Sales Agreement, the Company will set the parameters for the sale of shares, including the number of shares to be issued, the time period during which sales are requested to be made, any limits on the number of shares that may be sold in any one trading day and any minimum price below which sales may not be made. The Sales Agreement provides that Cowen will be entitled to compensation for its services equal to 3.0% of the gross proceeds from the sale of shares sold pursuant to the Sales Agreement. Sales under the ATM are limited by the greater of (i) the number of shares that are available to be issued or (ii) $50 million. The Company has no obligation to sell any shares under the Sales Agreement, and may at any time suspend solicitations and offers under the Sales Agreement. No shares had been sold under the Sales Agreement as of September 30, 2016. February 2015 Financing Common Stock On February 11, 2015, the Company closed on an underwritten offering of 13,500,000 shares of its common stock at a price to the public of $1.50 per share, for gross proceeds of approximately $20.3 million. As part of the common stock offering, the Company also granted the underwriters a 30-day option to purchase 2,025,000 additional shares of the Company's common stock. On February 18, 2015, the Company closed a partial exercise of the underwriter’s option to purchase 1,199,660 additional shares of the Company’s common stock, at a price to the public of $1.50 per share, which resulted in gross proceeds to the Company of approximately $1.8 million. Series B Convertible Preferred Stock In addition, on February 11, 2015, the Company closed on a concurrent but separate underwritten offering of 1,333 shares of its Series B convertible preferred stock at a price to the public of $1,500 per share, for gross proceeds of approximately $2.0 million. The Company designated 5,333 shares of its authorized and unissued preferred stock as Series B convertible preferred stock and filed a Certificate of Designation of Preferences, Rights and Limitations of Series B Convertible Preferred Stock with the Delaware Secretary of State. Concurrent but separate from this offering, the Company entered into an exchange agreement with certain affiliates of BVF to exchange 4,000,000 shares of common stock previously purchased by BVF for 4,000 shares of Series B convertible preferred stock. Each share of Series B convertible preferred stock is convertible into 1,000 shares of the Company’s common stock at any time at the holder’s option. The holder, however, will be prohibited from converting Series B convertible preferred stock into shares of common stock if, as a result of such conversion, the holder, together with its affiliates, would own more than 4.99% of the shares of the Company’s common stock then issued and outstanding, which percentage may be increased at the holders’ election up to 19.99% upon 61 days’ notice to the Company. In the event of the Company’s liquidation, dissolution, or winding up, holders of Series B convertible preferred stock will receive a payment equal to $0.0001 per share of Series B convertible preferred stock before any proceeds are distributed to the holders of common stock, after any proceeds are distributed to the holder of the Company’s Class UA preferred stock and on parity with any distributions to the holders of the Company’s Series A convertible preferred stock, Series C convertible preferred stock and Series D convertible preferred stock. Shares of Series B convertible preferred stock will generally have no voting rights, except as required by law and except that the consent of holders of a majority of the outstanding Series B convertible preferred stock will be required to amend the terms of the Series B convertible preferred stock. Shares of Series B convertible preferred stock will not be entitled to receive any dividends, unless and until specifically declared by the Company’s board of directors, and will rank: ● senior to all common stock; ● senior to any class or series of capital stock created that specifically ranks by its terms junior to the Series B convertible preferred stock; ● on parity with the Company’s Series A convertible preferred stock, Series C convertible preferred stock, and Series D convertible stock and any class or series of capital stock created that specifically ranks by its terms on parity with the Series B convertible preferred stock; and ● junior to the Company’s Class UA preferred stock and any class or series of capital stock created that specifically ranks by its terms senior to the Series B convertible preferred stock; in each case, as to distributions of assets upon the Company’s liquidation, dissolution or winding up whether voluntarily or involuntarily. Aggregate gross proceeds from the February 2015 offerings were approximately $24.0 million. Aggregate net proceeds from the February 2015 offerings, after underwriting discounts, commissions and expenses of $1.6 million, were approximately $22.4 million. Series C Convertible Preferred Stock On May 14, 2015, the Company designated 7,500 shares of its authorized and unissued preferred stock as Series C Convertible Preferred Stock and filed a Certificate of Designation of Preferences, Rights and Limitations of Series C Convertible Preferred Stock with the Delaware Secretary of State. The Company then entered into an exchange agreement with certain affiliates of BVF to exchange 7,500,000 shares of common stock previously purchased by BVF for 7,500 shares of Series C Convertible Preferred Stock. Each share of Series C Convertible Preferred Stock is convertible into 1,000 shares of the Company’s Common Stock at any time at the holder’s option. The holder, however, will be prohibited from converting Series C Convertible Preferred Stock into shares of common stock if, as a result of such conversion, the holder, together with its affiliates, would own more than 9.99% of the shares of the Company’s Common Stock then issued and outstanding. In the event of the Company’s liquidation, dissolution, or winding up, holders of Series C Convertible Preferred Stock will receive a payment equal to $0.0001 per share of Series C Convertible Preferred Stock before any proceeds are distributed to the holders of common stock, after any proceeds are distributed to the holder of the Company’s Class UA Preferred Stock and on parity with any distributions to the holders of the Company’s Series A Convertible Preferred Stock, Series B Convertible Preferred Stock, and Series D Convertible Preferred Stock. Shares of Series C Convertible Preferred Stock will generally have no voting rights, except as required by law and except that the consent of holders of a majority of the outstanding Series C Convertible Preferred Stock will be required to amend the terms of the Series C Convertible Preferred Stock. Shares of Series C Convertible Preferred Stock will not be entitled to receive any dividends, unless and until specifically declared by the Company’s board of directors, and will rank: • senior to all common stock; • senior to any class or series of capital stock hereafter created that specifically ranks by its terms junior to the Series C Convertible Preferred Stock; • on parity with the Company’s Series A Convertible Preferred Stock, Series B Convertible Preferred Stock, and Series D Convertible Stock and any class or series of capital stock created that specifically ranks by its terms on parity with the Series C Convertible Preferred Stock; and • junior to the Company’s Class UA Preferred Stock and any class or series of capital stock created that specifically ranks by its terms senior to the Series C Convertible Preferred Stock; in each case, as to distributions of assets upon the Company’s liquidation, dissolution or winding up whether voluntarily or involuntarily. |