How might the CMS decision on Biogen's Aduhelm impact other Alzheimer's candidates?
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Despite the Centers for Medicare & Medicaid Services' (CMS) decision on April 7 to severely limit coverage of Biogen's (NASDAQ:BIIB) Aduhelm (aducanumab) for Alzheimer's disease, other drugmakers are forging ahead with their candidates for the condition.
On Friday, Eisai (OTCPK:ESALY) said it expects to finish a rolling submission for a Biologics License Application (BLA) for lecanemab to the U.S. FDA under the accelerated approval pathway in Q1 fiscal 2022 (began April 1, 2022).
Eli Lilly (NYSE:LLY) is developing donanemab and also said Friday it is pressing ahead with its rolling application, which it expects to complete by the end of the year, Reuters reported. However, the drugmaker won't have phase 3 data available until mid-2023.
Roche (OTCQX:RHHBY) is expected to release late-stage data on its candidate, gantenerumab, by the end of the year, though it is not pursuing accelerated approval.
The CMS decision covers FDA-approved monoclonal antibodies that target amyloid protein using its reduction from the brain as a surrogate endpoint that is "reasonably likely to predict clinical benefit," but only in clinical trials.
That could leave Eisai (OTCPK:ESALF), Lilly (LLY), and Roche (OTCQX:RHHBY), like Biogen (BIIB) with Aduhelm, in precarious positions considering their candidates also target amyloid plaque reduction under the theory that removing amyloid slows cognitive decline. The problem is that researchers still aren't certain that this is the case.
One potential bright spot in the CMS decision is that the agency said it would cover approved antibodies based on direct clinical benefit -- such as proof of slowing cognitive decline -- in CMS-approved prospective comparative studies. Although the efficacy bar is significantly higher, this could benefit drugmakers as CMS noted study designs for these trials are less rigorous.
Such a study could include data generated from routine clinical practice or a registry. "Registry data may then be used to assess whether outcomes seen in carefully controlled clinical trials are reproduced in real-world use and in a broader range of patient groups," CMS wrote.
That could ultimately open the door to broader coverage determinations for other Alzheimer's drugs, and profits from them to drugmakers. But in order for this to happen, pharmaceutical companies will have to show their drugs lead to a meaningful slowing down of cognitive decline, something no treatment has yet to clearly demonstrate.