Medicare will begin covering GLP-1 drugs for obesity — not just diabetes — on July 1, with qualifying beneficiaries paying no more than $50 per month out of pocket. This is a landmark policy change: for the first time, the largest U.S. government insurer will explicitly fund weight-loss use of drugs like Eli Lilly's Zepbound (tirzepatide) and Novo Nordisk's Wegovy (semaglutide), covering a population of tens of millions of older Americans who were previously excluded.
For Eli Lilly, which posted $65.2B in revenue with a staggering 44.7% YoY growth and $22.95 diluted EPS, this opens a new demand channel without requiring new approvals. Amgen, reporting $36.8B in revenue at 10% YoY growth, is developing MariTide, an injectable, and has shown early obesity pipeline momentum — though it is not yet on the market with an approved obesity drug.
The bull case rests on volume: Medicare covers roughly 67 million Americans, and obesity prevalence among that cohort is high. Even modest penetration at the $50 cap could translate to significant unit volume and potentially higher reimbursement rates negotiated behind the scenes. Lilly's manufacturing buildout and dominant market position make it the clearest direct beneficiary.
The bear case is more nuanced. The $50/month cap compresses the revenue-per-patient figure that has driven LLY's explosive top-line growth; Medicare price negotiation under the IRA creates ongoing reimbursement pressure. Muscle loss side effects flagged in the article may also dampen uptake among older adults and their physicians. Amgen's pipeline candidate is still pre-commercial, making any near-term uplift speculative.
The key watch items are: (1) actual uptake data beginning Q3 2025, (2) whether the $50 cap materially compresses LLY's GLP-1 ASPs, and (3) Amgen's MariTide Phase 3 readout timeline — a positive result would re-rate AMGN as a credible second player in the Medicare obesity market.