Billy Dunn, a top Food and Drug Administration official who played a key role in recent approvals of new therapies for Alzheimer’s and ALS, is leaving the agency.
His departure was announced in an email to FDA staff sent by Peter Stein, head of the regulator’s Office of New Drugs.
“It was with regret that I announce the departure of Dr. Billy Dunn, Director of the Office of Neuroscience,” Stein wrote in the email. “After a long and highly productive career in public service, Billy has decided to retire from FDA and explore other opportunities while continuing his focus on improving the lives of patients with neurological diseases.”
Teresa Buracchio, an FDA veteran and currently the acting deputy director of the Office of Neuroscience, will take Dunn’s place on an acting basis. She has also been appointed to the deputy director role on a permanent basis, Stein wrote.
Dunn, who joined the FDA in 2005 from the National Institute of Neurological Disorders and Stroke, rose through the regulator’s ranks, becoming director of the then Division of Neurological Products in 2013. He is the first director of the Office of Neuroscience, a group he helped design and stand up, according to Stein’s email.
“He has made a major impact in how drugs are developed for a range of serious neurological diseases — many that previously had only limited treatment options,” Stein wrote.
While Dunn had gained a reputation as a tough overseer of drug standards, he became a more controversial figure after the FDA’s 2021 approval of Biogen’s Alzheimer’s drug Aduhelm — a decision he was closely involved in. Reporting by Stat News documented an informal, off-the-books meeting Dunn held with Biogen’s then head of R&D Al Sandrock in early 2019, which helped cement an unusually close collaboration between the agency and the drugmaker in Aduhelm’s review. That relationship later came under scrutiny by lawmakers and federal investigators, and the consumer advocate group Public Citizen called for Dunn’s resignation, among other officials..
More recently, Dunn oversaw his office’s approval of Eisai and Biogen’s Alzheimer’s drug Leqembi, a decision that, while less debated, was nevertheless a major commitment by the agency to a disputed hypothesis around how Alzheimer’s disease develops.
Dunn also played a notable role in securing the support of FDA advisers for an ALS drug, Amylyx Pharmaceuticals’ Relyvrio, that was similarly viewed as a test case for the agency’s standards for supporting clinical trial evidence.
His exit could cause “reverberations” through the industry, wrote Brian Abrahams, an analyst at RBC Capital Markets, in a note to clients.
One drug company that felt an immediate impact was Reata Pharmaceuticals, which is expecting an FDA decision on its drug for the inherited nerve disease Friedrich’s ataxia this week. Shares fell by more than a third on the news as analysts on Wall Street have viewed Dunn’s oversight of the review as supporting a potential approval.
The stock drop, wrote Baird analyst Brian Skorney in a Monday note, “isn’t surprising given the nearly unanimous view on the street that [Reata’s drug] wouldn’t stand a snowball’s chance under the review of any other Officer/Director at FDA.”
Editor’s note: This story has been updated to include analyst commentary.