THOR Synthorx Inc

Synthorx, Inc. (NASDAQ: THOR), a biotechnology company using a first-of-its-kind Expanded Genetic Alphabet platform technology to discover and develop optimized biologics for cancer and autoimmune disorders, today announced the appointment of Andrew Powell, J.D., to its board of directors. In addition, current board member Pratik Shah, Ph.D., has been appointed chairman of the board.

“Mr. Powell’s deep-rooted experience in transforming life science companies over the past 30 years—including his management of fast-changing organizations, his involvement in organizational growth, as well as his guidance as a director of several public companies—will bring a unique and dynamic perspective to our board of directors,” said Laura Shawver, Ph.D., chief executive officer of Synthorx.

Mr. Powell is a senior executive with 30 years of global life sciences experience transforming dynamic companies working in oncology, dermatology, nephrology and pulmonology. He has over 13 years of public company boardroom experience, and he is a current board member of Aclaris Therapeutics and Landec. Previously, Mr. Powell has served as the senior vice president, general counsel and corporate secretary of Medivation (acquired by Pfizer), InterMune (acquired by Roche/Genentech), Cornerstone Therapeutics (acquired by Chiesi), Imclone Systems (acquired by Eli Lilly) and Collagenex Pharmaceuticals (acquired by Galderma). He has also served as vice president, chief international counsel at Baxter International, as well as an associate of Gibson, Dunn & Crutcher, a multinational law firm. Mr. Powell received his J.D. from Stanford University and his B.A. in English from the University of North Carolina at Chapel Hill.

About Synthorx Synthorx, Inc. is a biotechnology company focused on prolonging and improving the lives of people with cancer and autoimmune disorders. Synthorx’s proprietary, first-of-its-kind Expanded Genetic Alphabet platform technology expands the genetic code by adding a new DNA base pair and is designed to create optimized biologics, referred to as Synthorins. A Synthorin is a protein optimized through incorporation of novel amino acids encoded by the new DNA base pair that enables site-specific modifications, which enhance the pharmacological properties of these therapeutics. The company’s lead product candidate, THOR-707, a variant of IL-2, is in development in multiple tumor types as a single agent and in combination with an immune checkpoint inhibitor. The company was founded based on important discoveries in Dr. Floyd Romesberg’s lab at The Scripps Research Institute. The company is headquartered in La Jolla, Calif.

Corporate Development Contact: Enoch Kariuki, Pharm.D.Synthorx, Inc.ekariuki@synthorx.com 858-750-4750

Media Relations Contact:Lauren FishCanale Communicationslauren@canalecomm.com619-849-5386