- Two influential groups in the drugmaking industry will take a closer look at an experimental medicine that could become the first-ever treatment approved to alter the course of Alzheimer's disease.
- The Peripheral and Central Nervous System Drugs Advisory Committee, which consists of experts who evaluate drugs' merits and risks and then make approval recommendations to the Food and Drug Administration, will meet on Nov. 6 to review Biogen's aducanumab. While the FDA isn't bound to follow the verdicts of advisory committees, it usually does.
- Meanwhile, the drug price watchdog ICER — short for the Institute for Clinical and Economic Review — said Monday that it, too, will assess the data and potential value of aducanumab as an Alzheimer's treatment. ICER will contact key patient groups and clinical experts over the coming weeks to better inform its report. The group is also accepting public input until Oct. 16. The report's conclusions will be made public at a meeting of the California Technology Assessment Forum in May 2021, according to ICER.
The FDA's review of aducanumab, which was initiated last month and given a deadline of March 7, 2021, is already one of the most closely watched in the agency's history.
Currently available Alzheimer's medications help alleviate symptoms. But if aducanumab gets approved, it would be the first drug advertised to treat what many researchers believe is the root cause of the neurodegenerative disorder. Given the unmet need and the millions of Alzheimer's patients living in the U.S., it's expected that aducanumab would quickly grow to a billion-dollar product if it comes to market.
Clearing that final hurdle could be a major challenge, though. The data Biogen used to support an approval came from two large clinical trials that, while identically designed, generated very different results. Biogen said one trial was a clear success, as patients with early Alzheimer's who were given high doses of aducanumab experienced significantly less decline on a cognitive test than patients given placebo. Yet results from the other trial showed the opposite effect, with patients on placebo doing better than those on the high-dose drug.
Efficacy might not be the only sticking point. Across both trials, just over a third of patients who received the high dose of aducanumab experienced brain swelling as a side effect, while about 18% had micro-hemorrhages. Biogen claimed the side effects were mostly mild and manageable; but for a drug that could be used in a decent portion of the population, they may be hard for regulators to get past.
Against this backdrop of uncertainty, Wall Street has been conservative about aducanumab's approval chances. Several investment banks have estimated the probability of such an outcome to be in the roughly 30% to 50% range.
"At a high level this all sounds great, but at the same time, there still are a ton of questions surrounding the aducanumab dataset," Stifel analyst Paul Matteis wrote in an August note to clients, following news that the FDA had agreed to review the drug.
The upcoming advisory committee meeting should provide some clarity about the most outstanding concerns the agency has with regard to aducanumab. These meetings typically see presentations from the drug's developer and from FDA staff, after which the committee discusses the pros and cons of the drug and its approval application. FDA scientists publish their stance in briefing documents at least a couple days before the committee meeting.
The public will have to wait longer before it knows ICER's views. The increasingly prominent drug pricing group has evaluated a wide assortment of high-profile treatments — including new medicines for asthma, cholesterol and peanut allergies — and often concluded they don't meet certain criteria for being cost-effective. Its decisions, in recent years, have begun to impact coverage decisions by insurers.
Cost will likely be a focal point as the FDA's decision deadline comes close. Even without a widely-used, potentially high-priced biologic drug, Alzheimer's already costs the healthcare system hundreds of billions of dollars annually, according to the Centers for Disease Control and Prevention.