Sienna Biopharmaceuticals, Inc. announced that Erle Mast has been appointed to Sienna’s Board of Directors. Mr. Mast will chair the Audit Committee. Mr. Mast was one of the co-founders of Clovis Oncology, Inc. and served as executive vice president and chief financial officer from the company’s inception in April 2009 until his retirement in March 2016. He is currently a member of the board of directors of Zogenix, Inc. (and previously served on the boards of directors and audit committees of Receptos, Inc., Somaxon Pharmaceuticals, Inc. and Verus Pharmaceuticals, Inc. Mr. Mast received a Bachelor of Science in business administration from California State University, Bakersfield.