Stockholders' Equity	12 Months Ended
Dec. 31, 2019
Stockholders' Equity
Stockholders' Equity	7. STOCKHOLDERS’ EQUITY On December 9, 2019, the Company completed an underwritten public offering of 20,000,000 shares of common stock at a price of $6.25 per share before underwriting discounts and commissions, or the 2019 Offering. In connection with the 2019 Offering, the Company entered into an underwriting agreement, or the 2019 Underwriting Agreement, with Citigroup Global Markets Inc., Cowen and Company LLC, SVB Leerink LLC and Piper Jaffray & Co., or collectively the 2019 Underwriters, pursuant to which the Company granted to the 2019 Underwriters a 30-day option to purchase up to an additional 3,000,000 shares of the Company’s common stock, or the 2019 Overallotment. The Company completed the sale of 23,000,000 shares, inclusive of the 2019 Overallotment, to the 2019 Underwriters and that sale resulted in the receipt by the Company of aggregate gross proceeds of approximately $143.8 million, less underwriting discounts, commissions and offering expenses totaling approximately $8.9 million, which resulted in net proceeds of approximately $134.9 million. On November 22, 2019, the Company and KKC entered into a stock purchase agreement, pursuant to which the Company sold an aggregate of 2,873,563 shares of its common stock at $6.96 per share for net proceeds of approximately $20.0 million, or the Private Placement. The Private Placement closed on November 25, 2019. On May 25, 2018, the Company completed an underwritten public offering of 12,500,000 shares of common stock at a price of $4.00 per share before underwriting discounts and commissions, or the 2018 Offering. In connection with the 2018 Offering, the Company entered into an underwriting agreement, or the 2018 Underwriting Agreement, with Jefferies LLC and SVB Leerink (formerly known as Leerink Partners LLC), or together the 2018 Underwriters, pursuant to which the Company granted to the 2018 Underwriters a 30-day option to purchase up to an additional 1,875,000 shares of the Company’s common stock, or the 2018 Overallotment. The Company completed the sale of 14,375,000 shares, inclusive of the 2018 Overallotment, to the 2018 Underwriters, and that sale resulted in the receipt by the Company of aggregate gross proceeds of approximately $57.5 million, less underwriting discounts, commissions and offering expenses totaling approximately $3.7 million, which resulted in net proceeds of approximately $53.8 million.

7. STOCKHOLDERS’ EQUITY

On December 9, 2019, the Company completed an underwritten public offering of 20,000,000 shares of common stock at a price of $6.25 per share before underwriting discounts and commissions, or the 2019 Offering. In connection with the 2019 Offering, the Company entered into an underwriting agreement, or the 2019 Underwriting Agreement, with Citigroup Global Markets Inc., Cowen and Company LLC, SVB Leerink LLC and Piper Jaffray & Co., or collectively the 2019 Underwriters, pursuant to which the Company granted to the 2019 Underwriters a 30-day option to purchase up to an additional 3,000,000 shares of the Company’s common stock, or the 2019 Overallotment. The Company completed the sale of 23,000,000 shares, inclusive of the 2019 Overallotment, to the 2019 Underwriters and that sale resulted in the receipt by the Company of aggregate gross proceeds of approximately $143.8 million, less underwriting discounts, commissions and offering expenses totaling approximately $8.9 million, which resulted in net proceeds of approximately $134.9 million.

On November 22, 2019, the Company and KKC entered into a stock purchase agreement, pursuant to which the Company sold an aggregate of 2,873,563 shares of its common stock at $6.96 per share for net proceeds of approximately $20.0 million, or the Private Placement. The Private Placement closed on November 25, 2019.

On May 25, 2018, the Company completed an underwritten public offering of 12,500,000 shares of common stock at a price of $4.00 per share before underwriting discounts and commissions, or the 2018 Offering. In connection with the 2018 Offering, the Company entered into an underwriting agreement, or the 2018 Underwriting Agreement, with Jefferies LLC and SVB Leerink (formerly known as Leerink Partners LLC), or together the 2018 Underwriters, pursuant to which the Company granted to the 2018 Underwriters a 30-day option to purchase up to an additional 1,875,000 shares of the Company’s common stock, or the 2018 Overallotment. The Company completed the sale of 14,375,000 shares, inclusive of the 2018 Overallotment, to the 2018 Underwriters, and that sale resulted in the receipt by the Company of aggregate gross proceeds of approximately $57.5 million, less underwriting discounts, commissions and offering expenses totaling approximately $3.7 million, which resulted in net proceeds of approximately $53.8 million.