Biogen's Big Bet

For years, doctors and patients have been waiting for any signs of hope in the fight against Alzheimer's. The disease has devastating consequences across the world, and we're mostly helpless to stop it. In a sobering analysis earlier this year, my colleague Reshma Kapdia wrote: 

Alzheimer’s is a progressive brain disease that is the most common cause of dementia. Of the top 10 causes of death globally, it’s the only one that can’t be cured, slowed down, or prevented, at least not yet.

Some help finally arrived Monday. Maybe. The degree of optimism depends on your view of progress and how we benchmark medical success. The U.S. Food and Drug Administration approved an Alzheimer's treatment from Biogen called aducanumab. It's the FDA's first approval of a treatment for the disease since 2003. And this wasn't just any approval. In signing off on the drug, the FDA gave broad support for its use across all categories of Alzheimer's patients.

That move caught investors by surprise, notes Josh Nathan-Kazis. Biogen soared as much as 63% on the news before finishing up 38%. Other drugmakers rose in sympathy; Eli Lilly was the S&P 500's second-best performer, up 10%. 

Aducanumab will cost $56,000 a year. Here's more from Josh: 

The label on Biogen’s drug, aducanumab, is broad, meaning that its use is not restricted to certain categories of Alzheimer’s patients. Bernstein analyst Ronny Gal called the label “almost shockingly broad,” noting that it is approved for a population broader than that in which it was tested.

What’s more, the agency has also set a precedent for approving Alzheimer’s drugs based on their ability to clear beta amyloid plaques, which are thought to have a role in the disease.

“This is long-awaited good news for Biogen and for the Alzheimer’s space given the significant unmet need,” SVB Leerink analyst Marc Goodman wrote on Monday.

As of now, though, there's no clear evidence that the drug actually has a real-life benefit for patients, and that is stoking controversy among patients, doctors, and even investors. Josh cited several skeptical analysts today, including this quote from Citigroup analyst Mohit Bansal: 

“Unmet need wins over science as the FDA finds a way to approve the drug,” Bansal wrote. “The agency seems to have taken a stance to approve on biomarker of amyloid plaque reduction rather than the functional endpoint.”

The FDA said it was aware of the significant debate around the drug. In one part of her statement, FDA official Patrizia Cavazzoni said:

We ultimately decided to use the Accelerated Approval pathway—a pathway intended to provide earlier access to potentially valuable therapies for patients with serious diseases where there is an unmet need, and where there is an expectation of clinical benefit despite some residual uncertainty regarding that benefit.