Donanemab’s FDA Panel Approval: A Breakthrough Moment for Alzheimer’s—and a Cautionary Tale for Biotech

The committee’s decision, announced in late April 2025, cited robust findings from the TRAILBLAZER-ALZ 2 study, which demonstrated that Donanemab slowed cognitive and functional decline by approximately 35% compared to placebo over 18 months (Eli Lilly, 2025). Such results are unprecedented in a therapeutic landscape where modest improvements have typically been the ceiling of success.

Yet the excitement is tempered by significant caution. Like Biogen’s controversial Aduhelm before it, Donanemab targets beta-amyloid plaques in the brain—a strategy whose validity remains fiercely debated. Although amyloid clearance is associated with reduced progression in some patients, it has not consistently translated into meaningful clinical improvements across diverse populations. An editorial in The New England Journal of Medicine noted that while Donanemab’s results are encouraging, “caution must temper optimism until longer-term outcomes and real-world effectiveness are better understood” (NEJM, 2025).

Moreover, Donanemab carries serious risks. Participants in the trial experienced a higher rate of amyloid-related imaging abnormalities (ARIA), including brain swelling and microhemorrhages—side effects that will necessitate careful patient screening and monitoring (FDA Briefing Document, 2025).

From a policy perspective, the drug’s likely approval and high anticipated price tag—rumored to exceed $26,000 per year—raises pressing questions about healthcare access and equity. Experts warn that if Medicare coverage is limited or conditional, as it initially was with Aduhelm, patients could face substantial barriers to accessing the therapy. Writing in Health Affairs, Dr. Lisa Rosenbaum argues that “without reforms to how novel therapies are priced and reimbursed, breakthroughs risk becoming privileges for the few rather than benefits for the many” (Health Affairs, 2025).

Investors, meanwhile, are already treating Donanemab’s success as validation of biotech’s high-risk, high-reward ethos. Shares of Eli Lilly surged following the panel’s recommendation, reinforcing Wall Street’s belief that neurological therapeutics—once a graveyard of drug development—may finally be coming into its own. Analysts at Goldman Sachs revised upward their projections for the Alzheimer’s treatment market to $25 billion annually by 2030 (Goldman Sachs Healthcare Outlook, 2025).

Still, the deeper significance of Donanemab’s advance lies in what it reveals about the intersection of science, policy, and society. The drug may offer genuine relief for thousands of patients and families, but it also forces uncomfortable reckonings: How should we weigh moderate benefits against serious risks? Who deserves access to costly innovations? And how do we navigate the persistent gap between scientific breakthroughs and equitable healthcare delivery?

In the end, Donanemab’s story is not just about one drug—it is a microcosm of the tensions that define modern medicine: ambition and uncertainty, innovation and inequity, hope and hubris.