FDA warns: Weight-loss drugs may increase risk of irreversible vision loss

The FDA announced it will require GLP-1 drug manufacturers to add a warning about an increased risk of a rare optic nerve injury that can lead to permanent vision loss. The decision is based on an analysis of 126 clinical trials, but the FDA emphasizes that the risk is rare and a causal link has not yet been proven.

The U.S. Food and Drug Administration (FDA) announced it will require manufacturers of GLP-1 drugs to add a warning about an increased risk of a rare but serious optic nerve injury that can lead to permanent vision loss. The decision applies to Ozempic, Wegovy, Mounjaro, and Zepbound. It was made following an analysis of 126 clinical trials involving 134,253 patients, which showed 6.4 cases of optic nerve injury per 100,000 treatment years among GLP-1 users, compared to 3.8 in control groups – a 68% difference. However, the total number of cases was small (15 in total), and the FDA emphasizes that a causal link has not been proven. The condition, NAION, is caused by reduced blood supply to the optic nerve. The FDA does not recommend stopping treatment broadly, but rather reporting sudden vision loss. Meanwhile, shares of Eli Lilly and Novo Nordisk rose following positive Phase 3 trial results for the drug Foundayo and improved forecasts for Novo Nordisk.