Mirum Pharmaceuticals (NASDAQ: MIRM) has appointed Ed Tucker to serve as its chief medical officer. He was most recently the chief operating officer of AstraZeneca (NYSE: AZN) subsidiary Acerta Pharma. His experience also includes positions at Bayer, Janssen Pharmaceutica, and Genentech. Foster City, CA-based Mirum Pharma, which launched late last year, is developing drugs for liver diseases. In July, the company raised $75 million from its IPO.