The Food and Drug Administration (FDA) has mandated that drugmakers update the safety labels on glucagon-like peptide-1 receptor agonist (GLP-1) drugs, alerting patients and healthcare providers to a potential risk of nonarteritic anterior ischemic optic neuropathy (NAION), a condition that can lead to permanent blindness.
NAION occurs when blood flow to the front of the optic nerve is suddenly reduced. Symptoms may include painless vision loss in one eye, blurred vision, distorted colors, and hazy spots. The FDA advises patients experiencing these symptoms to contact their healthcare professional immediately.
The agency's decision follows a 2024 study that indicated diabetes patients taking semaglutide, the active ingredient in popular drugs like Ozempic and Wegovy, were four times more likely to develop NAION compared to those not on the medication. While the FDA noted study limitations, it determined that a further assessment of the potential increased risk was warranted.
The FDA conducted a comprehensive review of available data, including clinical trials, animal studies, post-marketing information, observational studies, and case reports. The agency found that cases of NAION had been reported across all currently marketed GLP-1 products. However, interpreting these reports was challenging due to overlapping risk factors for NAION and common conditions among patients using these medications. The FDA also stated it could not identify a clear mechanism by which GLP-1 drugs might increase the risk of NAION.
Despite these challenges, the FDA concluded that evidence suggests a potential increased risk of rare NAION events among users of GLP-1 drugs. The agency is urging healthcare providers to inform patients taking GLP-1s about the symptoms of NAION and to promptly refer patients suspected of having the condition to an ophthalmologist for evaluation. The FDA also suggested discontinuing GLP-1 RA treatment for patients who develop NAION, unless the benefits of the medication clearly outweigh the identified risk.
GLP-1 drugs, which mimic gut hormones to regulate appetite and blood sugar, have become widely prescribed for Type 2 diabetes and weight loss. Blockbuster treatments in this class include Ozempic, Wegovy, Zepbound, and Mounjaro. Some GLP-1s are also approved for cardiovascular risk reduction and other conditions. Common side effects of these drugs include gastrointestinal issues like nausea and vomiting, while less common but serious risks include gallbladder problems, pancreatitis, and kidney injury. The drug class also carries a boxed warning regarding a potential risk of thyroid tumors.
The FDA's warning comes as GLP-1s continue to grow in popularity, with ongoing research exploring their potential for a wider range of medical applications.