X0206 3 2017-03-15 0 0001422142 Aerpio Pharmaceuticals, Inc. NONE 0001609405 Khuong Chau Quang C/O AERPIO PHARMACEUTICALS, INC. 9987 CARVER ROAD, SUITE 420 CINCINNATI OH 25242 1 0 1 0 Common Stock 3653451 I See Footnotes These shares were acquired pursuant to an Agreement and Plan of Merger, dated as of March 7, 2017 (the "Merger Agreement"), pursuant to which a wholly-owned subsidiary of the Company merged with and into Aerpio Therapeutics, Inc. ("Aerpio"). Pursuant to the Merger Agreement, the then outstanding shares of Aerpio's common stock and outstanding shares of each series of Aerpio's preferred stock were cancelled and were automatically converted into the right to received shares of the Company's common stock on a 2.3336572-1 basis upon closing of the merger. These shares are held of record by OrbiMed Private Investments V, LP ("OPI V"). OrbiMed Capital GP V LLC ("GP V") is the sole general partner of OPI V, and OrbiMed Advisors LLC ("Advisors"), a registered adviser under the Investment Advisers Act of 1940, as amended, is the sole managing member of GP V. Samuel D. Isaly ("Isaly"), a natural person, is the managing member of, and holder of a controlling interest in, Advisors. By virtue of such relationships, GP V, Advisors and Isaly may be deemed to have voting and investment power with respect to the securities held by OPI V noted above and as a result may be deemed to have beneficial ownership over such securities. The Reporting Person is an employee of Advisors. Each of GP V, Advisors, Isaly and the Reporting Person disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its or his pecuniary interest therein, if any. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose. Exhibit 24.1: Limited Power of Attorney /s/ Chau Khuong 2017-03-17