Biogen Surges On Favorable FDA Briefing Doc For Alzheimer's Candidate

Biogen Inc BIIB shares were soaring Wednesday in reaction to an FDA  briefing document released ahead of Friday's Adcom meeting on the investigational Alzheimer's drug aducanumab, an amyloid beta-targeting antibody.

What Happened: The Study 302 that evaluated aducanumab showed primary evidence of effectiveness, and the results of Study 103 were appropriately viewed as supportive evidence of the effectiveness, according to the briefing document prepared by Biogen and the FDA for the panel members of the Peripheral and Central Nervous System Drugs Advisory Committee. 

Following a Type C meeting with the FDA after the termination of the Phase 3 studies on aducanumab, the studies were run virtually using statistical modeling and simulation, the briefing document sad. 

"Based on these results, the FDA and Biogen jointly concluded that early termination of the Phase 3 program did not compromise the ability to interpret the results."

Related Link: Why Biogen's Fortunes Hinge On Aducanumab Approval

On safety, FDA staffers agreed with the characterization of the safety profile for amyloid-related imaging abnormalities, or ARIA-E. ARIA-Es were the most common adverse event and mostly asymptomatic and transient.

"Aducanumab, when dosed at 10 mg/kg IV every 4 weeks after a titration period of 24 weeks, has an acceptable safety profile that would support use in individuals with Alzheimer's disease," the briefing document said, citing the company.

FDA staffers downplayed the issue by suggesting that if efficacy is demonstrated, then appropriate labeling language will address adverse reactions of concern.

The agency agreed that there does not appear to be a signal for increased suicidal ideation or behavior in patients treated with aducanumab.

FDA staffers also concurred that there is an urgent and unmet medical need for effective treatment for Alzheimer's.

Why It's Important: Alzheimer's drug development has proved tough terrain for several biopharma companies, with most of them giving up midway through the process. 

With 2.2 million Americans suffering from mild dementia due to Alzheimer's, and assuming uptake of aducanumab by one-third of these people at a price of $50,000 per year, Biogen could be in for $36 billion in annual revenue from the biologic, STAT News reported, citing Cowen.

Given Biogen's recent woes with Spinraza and Tecfidera, a green light for aducanumab could lift the biopharma's fortunes.

BIIB Price Action: Biogen shares were up 39.48% at $344.53 at last check Wednesday.

Related Link: The Week Ahead In Biotech (Nov. 1-7): Adcom Test For Biogen's Aducanumab, Alzheimer's Conference, SMID-cap Earnings