FDA orders GLP-1 medicine labels to warn of potential rare eye risk

The US Food and Drug Administration is requiring labels for all GLP-1 receptor agonist medicines to include a warning about a potential increased risk of a rare eye condition. Its November 9 safety communication covers medicines used for type 2 diabetes and weight management, including Ozempic, Wegovy, Mounjaro and Zepbound.

The condition, non-arteritic anterior ischemic optic neuropathy, or NAION, involves reduced blood flow to the front of the optic nerve. The FDA describes it as a rare cause of sudden, painless decreased vision in one eye, which can include permanent vision loss. The new information belongs in the labels' Warnings and Precautions section.

The agency reviewed clinical trials, animal data and reports collected after marketing. Across 126 trials, its analysis identified 15 probable events: ten among patients receiving GLP-1 medicines and five among placebo recipients. The reported rates were 6.4 and 3.8 events per 100,000 person-years respectively. Person-years measure combined follow-up time, not simply the number of people taking a medicine.

The FDA said reports can be difficult to interpret because risk factors for NAION overlap with conditions common among people prescribed these drugs. Its animal-data review did not identify a mechanism explaining how the medicines might increase risk, and results differed between comparison groups in an observational analysis.

The regulatory action adds a warning about a potential rare risk; it is not an announcement that every user will develop eye damage. The communication does not withdraw the medicines' approvals.