Related Party Transactions	6 Months Ended
Jun. 30, 2018
Related Party Transactions
Related Party Transactions	Note 10. Related Party Transactions Overview of Related Parties Youssef El Zein, a member of the Company’s Board until his resignation in October 2017, is a director and controlling stockholder of Pillar Invest Corporation (“Pillar Invest”), 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”) and Pillar Pharmaceuticals V, L.P. (“Pillar V”) and a limited partner of Pillar I, Pillar II, Pillar III, Pillar IV and Pillar V. Entities affiliated with Pillar Invest and Participations Besancon (“Besancon”), an investment fund advised by Pillar Invest having no affiliation with Mr. El Zein, Pillar I, Pillar II, Pillar III, Pillar IV, Pillar V or Pillar Invest (collectively, the “Pillar Investment Entities”), owned approximately 12% of the Company's common stock as of June 30, 2018. Julian C. Baker, a member of the Company’s Board, is a principal of Baker Bros. Advisors, LP. Baker Bros. Advisors, LP and certain of its affiliated funds (collectively, “Baker Brothers”) owned approximately 18% of the Company's common stock as of June 30, 2018. Additionally, one of the Company’s directors, Kelvin M. Neu, was an employee of Baker Bros. Advisors, LP as of June 30, 2018. Pillar Investment Entities During the six months ended June 30, 2018, Besancon exercised warrants to purchase 150,000 shares of the Company’s common stock at an exercise price of $3.76 per share for a total exercise price of approximately $0.6 million. Baker Brothers During the six months ended June 30, 2018, Baker Brothers exercised warrants to purchase 2,539,541 shares of the Company’s common stock at an exercise price of $3.76 per share for a total exercise price of approximately $9.5 million. As of June 30, 2018, Baker Brothers held pre-funded warrants to purchase up to 2,768,882 shares of the Company’s common stock at an exercise price of $0.08 per share. Note 10. Related Party Transactions (Continued) Board Fees Paid in Stock Pursuant to the Company’s director compensation program, in lieu of director board and committee fees incurred of $0.1 million during each of the six months ended June 30, 2018 and 2017, the Company issued 4,727 and 4,818 shares of its common stock, respectively, to certain of its directors. Director board and committee fees are paid in arrears (including fees paid in stock) 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 10. Related Party Transactions

Overview of Related Parties

Youssef El Zein, a member of the Company’s Board until his resignation in October 2017, is a director and controlling stockholder of Pillar Invest Corporation (“Pillar Invest”), 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”) and Pillar Pharmaceuticals V, L.P. (“Pillar V”) and a limited partner of Pillar I, Pillar II, Pillar III, Pillar IV and Pillar V. Entities affiliated with Pillar Invest and Participations Besancon (“Besancon”), an investment fund advised by Pillar Invest having no affiliation with Mr. El Zein, Pillar I, Pillar II, Pillar III, Pillar IV, Pillar V or Pillar Invest (collectively, the “Pillar Investment Entities”), owned approximately 12% of the Company's common stock as of June 30, 2018.

Julian C. Baker, a member of the Company’s Board, is a principal of Baker Bros. Advisors, LP. Baker Bros. Advisors, LP and certain of its affiliated funds (collectively, “Baker Brothers”) owned approximately 18% of the Company's common stock as of June 30, 2018. Additionally, one of the Company’s directors, Kelvin M. Neu, was an employee of Baker Bros. Advisors, LP as of June 30, 2018.

Pillar Investment Entities

During the six months ended June 30, 2018, Besancon exercised warrants to purchase 150,000 shares of the Company’s common stock at an exercise price of $3.76 per share for a total exercise price of approximately $0.6 million.

Baker Brothers

During the six months ended June 30, 2018, Baker Brothers exercised warrants to purchase 2,539,541 shares of the Company’s common stock at an exercise price of $3.76 per share for a total exercise price of approximately $9.5 million.

As of June 30, 2018, Baker Brothers held pre-funded warrants to purchase up to 2,768,882 shares of the Company’s common stock at an exercise price of $0.08 per share.

Note 10. Related Party Transactions (Continued)

Board Fees Paid in Stock

Pursuant to the Company’s director compensation program, in lieu of director board and committee fees incurred of $0.1 million during each of the six months ended June 30, 2018 and 2017, the Company issued 4,727 and 4,818 shares of its common stock, respectively, to certain of its directors. Director board and committee fees are paid in arrears (including fees paid in stock) and the number of shares issued was calculated based on the market closing price of the Company’s common stock on the issuance date.