Antidiabetic drug Semaglutide linked to potential vision loss: Study

Researchers say future study required to assess causality

Popular antidiabetic drug Semaglutide may be linked to a potential risk of vision loss, according to a study conducted by Boston-based researchers.  The market size of Semaglutide in 2024 is estimated at $27.55 billion, and it is expected to reach $50.34 billion by 2029, growing at a compound annual growth rate (CAGR) of 12.8 per cent. The drug is sold under the brand names Wegovy, Rybelsus, and Ozempic by Danish drug major Novo Nordisk.

The study titled ‘Risk of Nonarteritic Anterior Ischemic Optic Neuropathy in Patients Prescribed Semaglutide’ was published in the medical journal JAMA Ophthalmology. It suggested that constant use of Semaglutide (a glucagon-like-peptide 1 receptor agonist or GLP-1RA) may be linked to development of a condition called non-arteritic ischemic optic neuropathy (NAION). NAION, as the study claimed, is the second most common form of optic neuropathy, and is also a major cause of adult blindness. The incidence of NAION is 2-10 cases per 100,000 people.

“Our anecdotal clinical experience motivated us to study whether Semaglutide is associated with an increased risk of developing NAION,” the researchers said.

The researchers – Jimena Tatiana Hathaway, Madhura P Shah, David B Hathaway, among others - are affiliated with various institutions in Boston including Harvard TH Chan School of Public Health, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston.

The study (matched cohort study) conducted on 16,287 patients revealed a higher risk of NAION in patients prescribed Semaglutide compared with patients prescribed non–glucagon-like peptide receptor agonist medications for diabetes or obesity.

“The findings suggest a potential risk of NAION associated with prescriptions for Semaglutide, but future study is required to assess causality,” they said.

Among 16, 827 patients, 710 had Type 2 diabetes (194 prescribed Semaglutide; 516 prescribed non–GLP-1 RA antidiabetic medications. The median age was 59 years; 52 per cent were female, and 979 were overweight or obese. In the population with Type 2 diabetes, 17 NAION events occurred in patients prescribed Semaglutide versus six in the non-GLP-1 RA antidiabetes cohort. Over a period of 36 months, the cumulative incidence rates of NAION were 8.9 per cent for the Semaglutide group.

The analysis indicated that patients treated with Semaglutide had a higher risk of developing NAION compared to those on non-GLP-1 RA antidiabetes medications. Among overweight or obese patients, 20 NAION events in the Semaglutide group were reported versus three in the non–GLP–1 RA cohort. Thus, there was a 6.7 per cent cumulative incidence rate over 36 months.

Semaglutide (Ozempic; Novo Nordisk) was approved by the US Food and Drug Administration (FDA) in December 2017 to treat Type 2 diabetes and in December 2022 to treat obesity (typically at higher doses, as Wegovy by Novo Nordisk). Weekly new-to-brand prescriptions in the United States of these and other glucagon-like peptide receptor agonist (GLP-1 RA) drugs increased by approximately 60 per cent from 2021 to 2023, the researchers noted.

Doctors felt that more data was needed before coming to any conclusion.

Anoop Misra, Chairman of Fortis C-Doc Hospital for Diabetes and Allied Sciences, said, “Risk of Nonarteritic Anterior Ischemic Optic Neuropathy is found to be increased in patients prescribed Semaglutide in an observational study. Be advised, that more data are needed in better-performed studies. In my experience of more than 1,000 treated pts, no such cases were seen.”

• Semaglutide is a new class of drug in antidiabetes in the GLP-1 RA category
• The Semaglutide Market size is estimated at $27.55 billion in 2024, and is expected to reach $50.34 billion by 2029, growing at a CAGR of 12.8 percent
• The study (matched cohort study) on 16,287 patients revealed higher risk of NAION in patients prescribed semaglutide compared with patients prescribed non–GLP 1 RA  medications for diabetes or obesity
• NAION is the second most common form of optic neuropathy, and is also a major cause of adult blindness.