The popular weight-loss drugs Ozempic and Wegovy from Novo Nordisk have been found to be associated with an increased risk of a rare vision loss, nonarteritic anterior ischemic optic neuropathy (NAION). Doctors at Massachusetts Eye and Ear, affiliated with Harvard University, found that patients using these drugs had a significantly higher risk of developing NAION than those using other drugs.
According to research conducted on July 3 Eastern Time, patients using Ozempic and Wegovy to lose weight are more than seven times more likely to develop NAION than those using other weight-loss drugs, and this risk is also four times higher than other treatments for diabetes. This finding has been published in JAMA Ophthalmology this week.
However, the scope of this study is limited, based only on 37 patient records from the Massachusetts Eye and Ear Hospital, so its statistical power is limited. Therefore, Harvard researchers and other experts have indicated that the current research results are not sufficient to prove that these drugs are a direct cause of eye complications, and more large-scale verification is needed in more hospitals.
Neuro-ophthalmologist Susan Mollan from Birmingham, UK said, "I don't think the study's results are sufficient to make patients stop taking the drugs." She pointed out that there is currently no direct causal relationship that can be proven between drug use and eye complications, because some cases appeared months after medication. However, doctors have a responsibility to fully explain the potential risks to patients, especially those with certain visual impairments.
The weight-loss drugs of Novo Nordisk and its competitor Eli Lilly and Co are very popular, leading to a shortage of supply in the market, and both companies are working to solve this problem. As the main component of Ozempic and Wegovy, semaglutide has been studied for more than 15 years and is generally considered safe. But as the scope of these drugs' use expands, researchers are also closely monitoring whether new side effects may appear.
On Wednesday, Novo Nordisk's ADR fell more than 4.8%, hitting a new intraday low since June 4th.
The study is currently expanding its scope and covering more hospitals.
Some unusual cases at Massachusetts Eye and Ear Hospital have alarmed doctors. Some patients who took semaglutide had nonarteritic anterior ischemic optic neuropathy, a rare condition that usually causes permanent partial vision loss. About one in 10,000 to 50,000 people are affected each year, and there is currently no standard treatment method.
"We need to be more cautious in examining this potential risk, and if this serious condition is indeed related to the drugs, it will have a significant impact on our evaluation of the risk-benefit ratio of the drugs." Although Mahyar Etminan, a drug safety researcher at the University of British Columbia, did not participate in this study, he said.
"We need to be more cautious in examining this potential risk, and if this serious condition is indeed related to the drugs, it will have a significant impact on our evaluation of the risk-benefit ratio of the drugs." Although Mahyar Etminan, a drug safety researcher at the University of British Columbia, did not participate in this study, he said.
Etminan further pointed out that it is particularly important for those who take Wegovy for weight loss alone without other symptoms to understand this risk. He emphasized that since diabetes itself is one of the risk factors for eye diseases, it is still unclear how Ozempic or Wegovy could trigger this condition.
This study covers the records of 710 diabetic patients and 979 weight-loss drug users who have been treated at Massachusetts Eye and Ear Hospital since Ozempic was approved in December 2017. Researchers compared the incidence of NAION in patients who first used Ozempic or Wegovy with those who used other treatments. It is worth noting that this study did not include Mounjaro and Zepbound, two diabetes and obesity medications produced by Eli Lilly and Co.
Last summer, three patients with NAION visited a clinic one after another in a short period of time, and they were all using semaglutide, prompting Joseph Rizzo, director of the neuro-ophthalmology service at Massachusetts Eye and Ear Hospital and a professor at Harvard Medical School, to launch this study.
Currently, Professor Rizzo's team is planning to collaborate with other institutions to conduct a wider study that covers more hospitals. Professor Rizzo stated: "I hope that doctors and patients can understand this potential association. The current research results do not prove a direct causal relationship between drug use and eye diseases. For patients who have already experienced a decrease in vision, understanding this possible risk is essential, as it can help them make wise choices before starting treatment."