Biogen’s research chief Alfred Sandrock to retire

Biogen Inc (BIIB.O) said on Monday its research chief Alfred Sandrock, who led development of its Alzheimer’s disease drug Aduhelm, is leaving the company after a 23-year run.

The company said Sandrock will retire by the end of this year, and Priya Singhal will lead the research & development unit on an interim basis until a permanent successor is identified.

Sandrock has been the face of Biogen’s controversial drug Aduhelm, which was approved by U.S. Food and Drug Administration in June for its ability to remove sticky deposits of another protein called amyloid beta – a likely contributor to Alzheimer’s.

Many experts have questioned the FDA’S rationale for approving the drug without more definitive proof of benefit.

Sandrock, a Stanford University alumni, joined the drugmaker in 1998. He had served as the chief medical officer for Biogen for about eight years before joining its executive committee in 2015.