Medicare will restrict coverage of Biogen's controversial Alzheimer's treatment Aduhelm only to patients who take part in a rigorous clinical trial, the federal government announced Tuesday, a decision that would likely keep use of the drug low if finalized later this year.
After a six-month review, CMS said that the study results generated so far by the drug, which won Food and Drug Administration approval last June, were "insufficient to establish that the treatment is reasonable and necessary."
The decision, which is a draft and could be revised, will also cover other drugs that work in the same way to treat Alzheimer's disease. Following the FDA's approval of Aduhelm, Japan's Eisai and then Eli Lilly submitted experimental Alzheimer's drugs for clearance based on early trial data.
CMS will collect comments on its proposal over the next 30 days and plans to finalize its decision by April 11.
By approving Aduhelm, the FDA endorsed an unproven, but much studied, scientific hypothesis that removing a sticky protein called amyloid from the brain could slow the loss of cognition and function that occurs in Alzheimer's. CMS officials acknowledged it is plausible drugs that do this might be beneficial, but argued the uncertainty needs to be resolved with additional research.
"We do know based on some of the evidence that there may be potential promise with this treatment," Lee Fleisher, CMS' chief medical officer, said in a call with reporters Tuesday. "That's why it is critical for us to pursue additional scientific evidence; that we at CMS make the right decision."
Patients wanting to receive Aduhelm will need to enroll in a "randomized controlled trial," a type of study that selects some patients to receive a placebo. As a result, some patients might be less willing to pursue treatment than they would if Medicare had proposed wider coverage.
The draft determination offers some clarity about the status of the first new Alzheimer's drug approved in decades. Insurers have largely refrained from establishing policies on Aduhelm until Medicare, the government program that covers many of the patients most likely to receive the drug, made its position known.
As a result, relatively few patients have been treated with Aduhelm and sales, which totaled just $300,000 through September, have been dramatically lower than initially forecast.
"People can assume that, really, the launch is starting once you have reimbursement," Biogen CEO Michel Vounatsos said earlier this week, during a virtual presentation at J.P Morgan's annual healthcare conference.
The proposed decision by CMS, though not entirely unexpected, isn't a good outcome for Biogen, which had hoped coverage might match the prescribing criteria approved by the FDA.
In a statement, Biogen said the decision would "significantly limit patient access to an FDA-approved treatment" and noted that these types of frameworks "can take months to years to initiate."
Analysts at Cowen & Co. had anticipated the agency would settle on a determination like this as a sort of middleground stance, allowing for the collection of more evidence on Aduhelm while also offering "cover should future data from the class turn out worse than expected."
CMS chose, however, to specify coverage only when patients are enrolled in a randomized clinical trial, the most rigorous kind. Another option could have been to cover treatment through studies that follow patient outcomes but don't compare a therapy against a placebo or another drug.
"We have chosen the most rigorous form of coverage with evidence development in covering this class of FDA approved drugs," said Fleisher.
Aduhelm's effectiveness had been hotly debated among doctors even before the FDA cleared it for market. A panel of outside experts voted against approval and, when the agency later overruled their advice, several resigned.
Those concerns have persisted in the months since, in turn hampering Aduhelm's sales and adoption. A number of high-profile medical and academic centers, including the Cleveland Clinic, have refused to administer the drug.
Biogen shares fell about 7% in post-market trading Tuesday, while Lilly shares dropped 2%.
Editor's note: This story has been updated with additional detail throughout.