Related Party Transactions	3 Months Ended
Mar. 31, 2020
Related Party Transactions
Related Party Transactions	Note 11. Related Party Transactions Baker Brothers Julian C. Baker, a member of the Company’s Board until his resignation in September 2018, is a principal of Baker Bros. Advisors, LP. Additionally, Kelvin M. Neu, a member of Company’s Board until his resignation in June 2019, is an employee of Baker Bros. Advisors, LP. As of March 31, 2020, Baker Bros. Advisors, LP and certain of its affiliated funds (collectively, “Baker Brothers”) held sole voting power with respect to an aggregate of 4,608,786 shares of the Company’s common stock, representing approximately 15% of the Company's outstanding common stock. As of March 31, 2020, Baker Brothers held warrants to purchase up to 2,708,812 shares of the Company’s common stock at an exercise price of $0.08 per share, warrants to purchase up to 2,368,400 shares of the Company’s common stock (or, if Baker Brothers elects to exercise the warrants for shares of Series B1 Preferred Stock, 23,684 shares of Series B1 Preferred Stock), at an exercise price of $1.52 per share (or, if Baker Brothers elects to exercise the warrants for shares of Series B1 Preferred Stock, $152 per Series B1 Preferred Warrant Share). Pillar Investment Entities Youssef El Zein, a member of the Company’s board of directors until his resignation in October 2017, is a director and controlling stockholder of Pillar Invest Corporation, which is the general partner of Pillar Pharmaceuticals I, L.P. (“Pillar I”), Pillar Pharmaceuticals II, L.P. (“Pillar II”), Pillar Pharmaceuticals III, L.P. (“Pillar III”), Pillar Pharmaceuticals IV, L.P. (“Pillar IV”), Pillar Pharmaceuticals V, L.P. (“Pillar V”), Pillar Pharmaceuticals 6 L.P. (“Pillar 6”), and Pillar Partners Foundation, L.P. (“Pillar Partners”) (collectively, “Pillar”). As of March 31, 2020, Pillar owned approximately 11% of the Company's common stock. Subsequent to March 31, 2020, in April 2020, the Company sold shares of common stock and common stock warrants to Pillar Partners in a private placement transaction as more fully described in Note 13. Immediately following the private placement transaction, Pillar owned approximately 19% of the Company’s common stock. Board Fees Paid in Stock Pursuant to the Company’s director compensation program, in lieu of director board and committee fees of less than $0.1 million during each of the three months ended March 31, 2020 and 2019, the Company issued 56,014 and 13,719 shares of common stock, respectively, to certain of its directors. Director board and committee fees are paid in arrears and the number of shares issued was calculated based on the market closing price of the Company’s common stock on the issuance date.

Note 11. Related Party Transactions

Baker Brothers

Julian C. Baker, a member of the Company’s Board until his resignation in September 2018, is a principal of Baker Bros. Advisors, LP. Additionally, Kelvin M. Neu, a member of Company’s Board until his resignation in June 2019, is an employee of Baker Bros. Advisors, LP. As of March 31, 2020, Baker Bros. Advisors, LP and certain of its affiliated funds (collectively, “Baker Brothers”) held sole voting power with respect to an aggregate of 4,608,786 shares of the Company’s common stock, representing approximately 15% of the Company's outstanding common stock.

As of March 31, 2020, Baker Brothers held warrants to purchase up to 2,708,812 shares of the Company’s common stock at an exercise price of $0.08 per share, warrants to purchase up to 2,368,400 shares of the Company’s common stock (or, if Baker Brothers elects to exercise the warrants for shares of Series B1 Preferred Stock, 23,684 shares of Series B1 Preferred Stock), at an exercise price of $1.52 per share (or, if Baker Brothers elects to exercise the warrants for shares of Series B1 Preferred Stock, $152 per Series B1 Preferred Warrant Share).

Pillar Investment Entities

Youssef El Zein, a member of the Company’s board of directors until his resignation in October 2017, is a director and controlling stockholder of Pillar Invest Corporation, which is the general partner of Pillar Pharmaceuticals I, L.P. (“Pillar I”), Pillar Pharmaceuticals II, L.P. (“Pillar II”), Pillar Pharmaceuticals III, L.P. (“Pillar III”), Pillar Pharmaceuticals IV, L.P. (“Pillar IV”), Pillar Pharmaceuticals V, L.P. (“Pillar V”), Pillar Pharmaceuticals 6 L.P. (“Pillar 6”), and Pillar Partners Foundation, L.P. (“Pillar Partners”) (collectively, “Pillar”). As of March 31, 2020, Pillar owned approximately 11% of the Company's common stock.

Subsequent to March 31, 2020, in April 2020, the Company sold shares of common stock and common stock warrants to Pillar Partners in a private placement transaction as more fully described in Note 13. Immediately following the private placement transaction, Pillar owned approximately 19% of the Company’s common stock.

Board Fees Paid in Stock

Pursuant to the Company’s director compensation program, in lieu of director board and committee fees of less than $0.1 million during each of the three months ended March 31, 2020 and 2019, the Company issued 56,014 and 13,719 shares of common stock, respectively, to certain of its directors. Director board and committee fees are paid in arrears and the number of shares issued was calculated based on the market closing price of the Company’s common stock on the issuance date.