In a decision published Thursday, Medicare has finalized its coverage policy for Biogen Alzheimer’s drug Aduhelm. The agency has stuck closely to an earlier proposal that limits payment to patients who are enrolled in a clinical trial.

Patients on Medicare, the insurance program that covers most of the roughly 2 million people Biogen says are likely to benefit from Aduhelm, now face the prospect of bearing the cost of the drug themselves when they take it out of a study. The decision should therefore significantly reduce sales of the future blockbuster.

Reimbursement ceilings, which are largely in line with a draft decision issued by the Centers for Medicare and Medicaid Services in January, will also apply to future drugs in the same class as Aduhelm. This includes an Eli Lilly treatment that is expected to be filed with the Food and Drug Administration by the end of the year.

Despite “the potential promise of this treatment, there is currently not enough evidence demonstrating improved health outcomes to say it is reasonable and necessary for people on Medicare,” the chief medical officer said. of CMS Lee Fleisher in a statement.

“Medical innovation must include clinical trials that demonstrate benefits for patients. Conversely, covering a drug that has not been shown to be effective may incentivize the production, marketing and sale of equally ineffective drugs,” the agency explained in full. decision.

Biogen said the decision “effectively denies all Medicare beneficiaries access” to Aduhelm, which aims to slow cognitive decline in people with early-stage symptoms of Alzheimer’s. As it assesses the impact, the company said it is “considering its options carefully.”

Aduhelm received conditional approval in June under the FDA’s fast-track approval pathway, with the caveat that further trials were needed to show the drug does indeed slow cognitive decline and is safe. Following the approval of Azheimer’s first new treatment in 18 years, Azheimer’s patient groups launched a fierce advocacy campaign.

But the medical community pushed back, given the drug’s unproven clinical benefits and its $28,200 price tag. And in the run-up to the Medicare decision, fast-track approval has become the subject of debate in Congress.

The decision ends a concerted campaign by patient groups to get Medicare to reconsider its coverage limits. As part of this effort, the Alzheimer’s Association and other groups coordinated more than 400 meetings in which patients, caregivers and supporters called on members of Congress to pressure CMS to expand coverage.

In a statement Following the ruling, Harry Johns, CEO of the Azlheimer’s Association, said “CMS has created unnecessary barriers for people with Alzheimer’s disease.”

While most of the preliminary ruling remained intact, CMS slightly relaxed the trial requirements. Medicare will cover the drug for patients in randomized, controlled clinical trials conducted by the FDA or the National Institutes of Health.

“While we note that CMS has expanded to where these clinical trials can take place, in reality it remains an unnecessary and never-before-imposed barrier to accessing an FDA-approved treatment,” Johns added.

The policy makes it clear that drugs approved through the conditional or fast track will be subject to these same strict coverage requirements. However, CMS said it would consider full coverage of future monoclonal antibody drugs directed against amyloid plaque, should these agents receive full FDA approval.

“The decision eliminates the fast-track approval pathway as a viable option for the class, but left the door open to drugs that guarantee approval by strict clinical criteria,” wrote Raymond James analyst Danielle Brill, in a note to investors.

In its decision, however, CMS pledged to base the coverage restrictions on the evidence submitted at the trials. Drugmakers developing future treatments for Alzheimer’s disease will need to present positive cognitive data not only for approval, but also for Medicare coverage.

“Ph. 3 positive cognitive data is already a high bar for success and CMS has effectively just raised that bar even higher,” Brill added in his note. “In our view, the future of the entire class of anti-amyloid antibodies is still up in the air.”