FDA Flags 15 Potential Cases of “Eye Stroke,” Seeks Updated Labels for GLP-1 Drugs
Key Facts
On November 9, the U.S. Food and Drug Administration asked holders of licenses for all GLP-1 drugs to add information about the potential risk of nonarteritic anterior ischemic optic neuropathy, known as “eye stroke,” to the “Warnings and Precautions” section of their labels. The request covers Ozempic, Wegovy, Mounjaro and Zepbound, among a broader class of treatments. The agency described the condition as rare and potentially capable of causing permanent vision loss. The action followed an assessment of clinical trial, animal and postmarketing data, including observational studies and case reports. Eli Lilly, which makes Mounjaro and Zepbound, closed at 1,411.95 dollars in the November 9 session; the closing data do not include anything linking the stock’s movement to the agency’s decision.
In an FDA meta-analysis, the agency pooled results from 126 randomized controlled trials involving 134,253 patients. The analysis identified 15 likely cases of NAION, including 10 among recipients of GLP-1 drugs and five among placebo recipients. The rate was 6.4 per 100,000 person-years among users of the class, compared with 3.8 in the comparison group. The agency said these findings were among the elements of its assessment of the potential risk. The observed numbers remain limited relative to the total number of trial participants, while the FDA described the condition itself as rare.
An FDA retrospective study using the Sentinel System provided another comparison between different treatments. The study followed adults with type 2 diabetes who began treatment between 2019 and 2024, and found no statistically significant increase in NAION risk among GLP-1 users compared with users of SGLT-2 inhibitors; the estimated hazard ratio was 1.19, with a 95% confidence interval of 0.91 to 1.54. By contrast, it found an increase compared with DPP-4 inhibitors, with a hazard ratio of 1.43 and a confidence interval of 1.02 to 2.01. Incidence rates across the study groups ranged from 26 to 32 per 100,000 person-years. The GLP-1 group recorded a rate of 30–32, compared with 31 for SGLT-2 inhibitors and 26 for DPP-4 inhibitors.
The FDA puts these rates in the context of its estimate of the rate among adults over age 50 in the general population, which ranges from 2.3 to 10.2 cases per 100,000 people annually. The agency also said its review of available animal data did not identify a mechanism explaining how GLP-1 use could increase the potential risk. Adverse-event reports were difficult to interpret because NAION risk factors overlap with conditions common among patients who use these drugs. The FDA therefore assessed other data sources alongside the reports. This assessment does not provide a definitive biological explanation for the potential link.
The FDA began assessing the potential link after a study published in July 2024 examined NAION cases among patients prescribed semaglutide. The agency said it identified several limitations in the study but considered its findings to warrant further assessment. Reports about the study said it found an association and did not establish causation. GLP-1 drugs are used to treat type 2 diabetes or to reduce weight and maintain weight loss over the long term. Some also have other approved uses, including reducing cardiovascular and kidney risks, and treating obstructive sleep apnea and metabolic dysfunction-associated steatohepatitis.
The FDA recommended that patients immediately tell their health care provider if they experience sudden, painless vision loss or visual disturbances in one eye. Doctors should promptly refer suspected cases to an ophthalmologist. If the condition develops into NAION, the agency recommended considering stopping the GLP-1 drug unless the benefits of treatment outweigh its risks. An Eli Lilly spokesperson said the company “is carefully evaluating the update and will respond to the FDA promptly.” The label update places the potential risk among the information patients and health care providers should review when assessing treatment.