Stockholders’ Equity	3 Months Ended
Mar. 31, 2020
Equity [Abstract]
Stockholders’ Equity	9. Stockholders’ Equity On January 17, 2017, the Company entered into a Controlled Equity Offering Sales Agreement, or the Sales Agreement, with Cantor Fitzgerald & Co. as sales agent, or Cantor. On July 7, 2017, the Company entered into an amendment to the Sales Agreement to increase the maximum aggregate offering price of the shares of common stock that it may issue and sell from time to time under the Sales Agreement from $40,000,000 to $80,000,000. Under the Sales Agreement, as amended, or the Amended Sales Agreement, Cantor may sell shares of the Company’s common stock by methods deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on the Nasdaq Global Select Market or on any other existing trading market for the Company’s common stock. The Company is not obligated to make any sales of shares of its common stock under the Amended Sales Agreement. The Company or Cantor may suspend or terminate the offering of shares of the Company’s common stock upon notice to the other party and subject to other conditions. The Company will pay Cantor a commission rate equal to 3.0% of the gross proceeds per share sold. As of March 31, 2020, the Company had sold an aggregate of 305,522 shares of common stock under the Sales Agreement, at an average selling price of approximately $129.80 per share for aggregate gross proceeds of $39.6 million and net proceeds of $38.2 million after deducting sales commissions and offering expenses. The Company did not sell any shares of common stock under the Sales Agreement during the three months ended March 31, 2020. As of May 6, 2020, $40.4 million of common stock remained available to be sold under the Amended Sales Agreement. On November 1, 2019 the Company completed a registered direct offering with Armistice Capital, LLC, a healthcare-focused institutional investor priced at-the-market, of (i) 300,000 shares of common stock and accompanying warrants to purchase an aggregate of 300,000 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 1,830,493 shares of common stock and accompanying warrants to purchase an aggregate of 1,830,493 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.755, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $3.745. Each pre-funded warrant has an exercise price of $0.01 per share, is exercisable immediately and is exercisable until exercised in full. Each common stock warrant has an exercise price of $3.62 per share, is exercisable immediately and expires five years from the date of issuance. The net proceeds to the Company from the offering, after deducting the placement agent's fees and other offering expenses payable by the Company, was approximately $7.1 million. The fair value allocated to the common stock, warrants and pre-funded warrants, less issuance costs, was $0.6 million, $2.9 million and $3.6 million, respectively. In November 2019, 400,000 of the pre-funded warrants were exercised. On January 24, 2020, the Company completed a private placement with Armistice Capital, LLC, a healthcare-focused institutional investor priced at-the-market of (i) 1,270,000 shares of common stock and accompanying warrants to purchase an aggregate of 1,270,000 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 2,063,334 shares of common stock and accompanying warrants to purchase up to an aggregate of 2,063,334 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.00, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $2.999, for gross proceeds of approximately $10.0 million. Each pre-funded warrant had an exercise price of $0.001 per share, was exercisable immediately and was exercisable until all of the pre-funded warrants are exercised in full. Each common stock warrant had an exercise price of $2.87 per share, was exercisable immediately and will expire five years from the date of issuance. Also on January 24, 2020, the Company completed a registered direct offering to certain healthcare-focused institutional investors priced at-the-market, of (i) 2,380,105 shares of common stock and accompanying warrants to purchase up to an aggregate of 2,380,105 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 120,000 shares of common stock and accompanying warrants to purchase up to an aggregate of 120,000 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.00, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $2.999, for gross proceeds of approximately $7.5 million. Each pre-funded warrant had an exercise price of $0.001 per share, was exercisable immediately and was exercisable until all of the pre-funded warrants are exercised in full. Each common stock warrant had an exercise price of $2.87 per share, was exercisable immediately and will expire five years from the date of issuance. The net proceeds to the Company from the registered direct offering and the concurrent private placement, after deducting the placement agent's fees and other offering expenses payable by the Company, were approximately $15.9 million.

Stockholders’ Equity

3 Months Ended

Mar. 31, 2020

9. Stockholders’ Equity

On January 17, 2017, the Company entered into a Controlled Equity Offering Sales Agreement, or the Sales Agreement, with Cantor Fitzgerald & Co. as sales agent, or Cantor. On July 7, 2017, the Company entered into an amendment to the Sales Agreement to increase the maximum aggregate offering price of the shares of common stock that it may issue and sell from time to time under the Sales Agreement from $40,000,000 to $80,000,000.

Under the Sales Agreement, as amended, or the Amended Sales Agreement, Cantor may sell shares of the Company’s common stock by methods deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on the Nasdaq Global Select Market or on any other existing trading market for the Company’s common stock.

The Company is not obligated to make any sales of shares of its common stock under the Amended Sales Agreement. The Company or Cantor may suspend or terminate the offering of shares of the Company’s common stock upon notice to the other party and subject to other conditions. The Company will pay Cantor a commission rate equal to 3.0% of the gross proceeds per share sold.

As of March 31, 2020, the Company had sold an aggregate of 305,522 shares of common stock under the Sales Agreement, at an average selling price of approximately $129.80 per share for aggregate gross proceeds of $39.6 million and net proceeds of $38.2 million after deducting sales commissions and offering expenses. The Company did not sell any shares of common stock under the Sales Agreement during the three months ended March 31, 2020. As of May 6, 2020, $40.4 million of common stock remained available to be sold under the Amended Sales Agreement.

On November 1, 2019 the Company completed a registered direct offering with Armistice Capital, LLC, a healthcare-focused institutional investor priced at-the-market, of (i) 300,000 shares of common stock and accompanying warrants to purchase an aggregate of 300,000 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 1,830,493 shares of common stock and accompanying warrants to purchase an aggregate of 1,830,493 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.755, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $3.745. Each pre-funded warrant has an exercise price of $0.01 per share, is exercisable immediately and is exercisable until exercised in full. Each common stock warrant has an exercise price of $3.62 per share, is exercisable immediately and expires five years from the date of issuance. The net proceeds to the Company from the offering, after deducting the placement agent's fees and other offering expenses payable by the Company, was approximately $7.1 million. The fair value allocated to the common stock, warrants and pre-funded warrants, less issuance costs, was $0.6 million, $2.9 million and $3.6 million, respectively. In November 2019, 400,000 of the pre-funded warrants were exercised.

On January 24, 2020, the Company completed a private placement with Armistice Capital, LLC, a healthcare-focused institutional investor priced at-the-market of (i) 1,270,000 shares of common stock and accompanying warrants to purchase an aggregate of 1,270,000 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 2,063,334 shares of common stock and accompanying warrants to purchase up to an aggregate of 2,063,334 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.00, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $2.999, for gross proceeds of approximately $10.0 million. Each pre-funded warrant had an exercise price of $0.001 per share, was exercisable immediately and was exercisable until all of the pre-funded warrants are exercised in full. Each common stock warrant had an exercise price of $2.87 per share, was exercisable immediately and will expire five years from the date of issuance.

Also on January 24, 2020, the Company completed a registered direct offering to certain healthcare-focused institutional investors priced at-the-market, of (i) 2,380,105 shares of common stock and accompanying warrants to purchase up to an aggregate of 2,380,105 shares of common stock, and (ii) pre-funded warrants to purchase up to an aggregate of 120,000 shares of common stock and accompanying warrants to purchase up to an aggregate of 120,000 shares of common stock. Each share of common stock and accompanying common stock warrant were sold together at a combined price of $3.00, and each pre-funded warrant and accompanying common stock warrant were sold together at a combined price of $2.999, for gross proceeds of approximately $7.5 million. Each pre-funded warrant had an exercise price of $0.001 per share, was exercisable immediately and was exercisable until all of the pre-funded warrants are exercised in full. Each common stock warrant had an exercise price of $2.87 per share, was exercisable immediately and will expire five years from the date of issuance.

The net proceeds to the Company from the registered direct offering and the concurrent private placement, after deducting the placement agent's fees and other offering expenses payable by the Company, were approximately $15.9 million.