US FDA Orders Safety Label Updates for GLP-1 Drugs Over Potential Eye Risk

The US Food and Drug Administration has instructed manufacturers of GLP-1 receptor agonist medications to add a warning regarding a rare eye condition called NAION. The decision follows a comprehensive review of clinical trials, real-world data, and observational studies.

NEW DELHI: The US Food and Drug Administration (FDA) has directed makers of all GLP-1 receptor agonist medicines to update their product labels with a warning regarding a possible link to a rare eye condition that can lead to permanent vision loss.

In a drug safety communication issued on November 9, the agency stated that these medications may be associated with non-arteritic anterior ischemic optic neuropathy (NAION), a condition that occurs when blood flow to the optic nerve is reduced. The condition can result in sudden, painless loss of vision in one eye, and the damage can occasionally be permanent. Manufacturers are required to place this information in the "Warnings and Precautions" section of their product documentation.

The affected drug class includes widely prescribed medications such as semaglutide (marketed as Ozempic, Wegovy, and Rybelsus), liraglutide (Victoza, Saxenda), dulaglutide (Trulicity), and tirzepatide (Mounjaro, Zepbound). These drugs are primarily utilized for managing type 2 diabetes and obesity, while certain formulations are also approved to lower heart and kidney risks.

The FDA reached its regulatory decision following an evaluation of clinical trials, animal studies, post-market reports, and observational research. A meta-analysis encompassing 126 trials with 134,253 participants identified 15 probable cases of NAION. Among these, ten cases occurred in individuals taking GLP-1 drugs, five in those receiving a placebo, and none among patients taking alternative non-GLP-1 diabetes treatments. The calculated rate stood at 6.4 cases per 100,000 person-years for GLP-1 users, compared to 3.8 for comparison treatments.

Additionally, the FDA conducted a real-world study of type 2 diabetes patients who initiated GLP-1 medications between 2019 and 2024. When compared to patients prescribed SGLT-2 inhibitors, the study found no statistically significant increase in risk. However, compared to patients on DPP-4 inhibitors, the risk was observed to be higher. The agency noted that it received NAION reports for every GLP-1 product currently on the market.

Despite these findings, the FDA emphasized that the existing evidence points only to a possible increased risk and does not conclusively prove that the drugs cause the condition. Furthermore, a review of animal data did not provide an explanation for how these medications might elevate this risk.

Medical guidance advises patients to seek immediate medical attention if they experience sudden, painless vision loss in one eye, blurred vision, blind spots, tunnel vision, distorted colors, or reduced central vision, which may first be noticed upon waking. Doctors have been instructed to refer suspected NAION cases promptly to eye specialists and to weigh the continuation of the GLP-1 therapy against its benefits.

"Regulatory updates of this nature highlight the continuous monitoring that pharmaceutical products undergo long after entering the market. For businesses and investors in the healthcare and pharmaceutical sectors, safety communications from regulatory bodies like the FDA underscore the critical importance of rigorous post-market surveillance, comprehensive risk assessment, and transparent communication with healthcare providers and patients alike." — Dr. Shishir Gupta, Founder & CEO, StartupLanes