Healthy Returns: Novo Nordisk's Ozempic faces scrutiny over potential link to rare eye condition

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There may be a new, unintended side effect linked to Novo Nordisk's blockbuster diabetes injection, Ozempic. 

Danish health authorities on Monday said they are asking the European Union's drug regulator to review the findings of two Danish studies linking Ozempic to an increased risk of a rare vision-threatening eye condition in Type 2 diabetes patients. 

The condition is called non-arteritic anterior ischemic optic neuropathy, or NAION. It is characterized by vision loss due to decreased blood flow to the front part of the optic nerve, which connects the eye to the brain. 

The disease typically occurs without any pain and most commonly affects people ages 50 and above. NAION affects between 2.3 and 10.3 patients per 100,000 people per year in the U.S., according to some estimates. 

The Danish Medicines Agency said it has kept close tabs on NAION as a possible adverse effect of semaglutide, the active ingredient in Ozempic, over the last six months. The agency received 19 reports of the condition in Denmark as of Dec. 10. 

But the overall number of NAION cases in Denmark has increased since Ozempic was introduced in the Danish market in 2018, Jakob Grauslund, professor in eye diseases at the University of Southern Denmark, or SDU, said in a release Monday. Denmark used to see around 60 to 70 cases a year but now has up to 150, added Grauslund, who helped conduct one of the studies. 

It's the latest potential concern about popular GLP-1s such as Ozempic, which mimic gut hormones to regulate blood sugar and tamp down appetite. Demand for the drug class has soared despite hefty price tags and a handful of unpleasant side effects that are most commonly gastrointestinal, such as nausea and vomiting. 

In a statement Monday, Novo Nordisk said after a "thorough evaluation of the studies" and an internal safety assessment, the Danish drugmaker is "of the opinion that the benefit-risk profile of semaglutide remains unchanged." The company added that patient safety was a top priority. 

The studies, conducted independently by SDU researchers and other institutions, both found that diabetes patients who used Ozempic were more than twice as likely to be diagnosed with the condition than those who took another diabetes drug. 

The first Danish study was based on data from more than 400,000 diabetes patients, a quarter of whom were treated with Ozempic and the rest with other diabetes drugs. The second study involved data from more than 44,000 Danish diabetes patients who received Ozempic between 2018 and 2024 and nearly 17,000 Norwegian patients who took the drug between 2018 and 2022. 

The studies were posted on medRxiv, a website that posts studies before they've been reviewed by outside scientists. Both appear to confirm a link first suggested in a Harvard University study earlier this year. 

Still, the authors of the first SDU study said that the absolute risk of the condition among semaglutide users is low. They added that assuming the risk remains constant over time, the results indicate that a diabetes patient taking Ozempic for 20 years would have a 0.3% to 0.5% chance of developing NAION. 

"Although our findings thereby do not rule out the possibility of an increased risk of NAION when using semaglutide for obesity, the low number of observed events suggests that any potential risk is likely of limited absolute magnitude," the authors of the first study said. 

They added that additional analyses that are designed differently are needed to further investigate whether Wegovy users, who take semaglutide for obesity, also have an increased risk of the condition.

For now, analysts are less concerned about the risk of NAION and its potential to reduce prescriptions of Ozempic.

"Unless semaglutide is found to be unique among GLP-1s in harboring this risk, prescribing [is] not likely to be affected," TD Cowen analyst Michael Nedelcovych said in a research note on Monday.

Feel free to send any tips, suggestions, story ideas and data to Annika at annikakim.constantino@nbcuni.com.

If physicians have their way, telehealth is here to stay. That's according to a new report from Doximity, which found that 83% of doctors would like telemedicine to remain "a permanent part of their clinical practice."

Doximity runs a digital platform for medical professionals that has been likened to a LinkedIn for doctors. But users can do more than network and read news on Doximity, as the company also offers telemedicine tools like voice calls and video calls.

Since the company has some stake in the game, Doximity published a report on Tuesday that outlines the state of telemedicine in the U.S. and its role in health-care delivery. It surveyed 1,171 of its physician telemedicine users and 131 of its nurse practitioner telemedicine users in August. 

More than 77% of the doctors surveyed said they are using telehealth weekly, and 35% said they've incorporated the technology into their daily clinical practice. Nearly 90% of nurse practitioners said they use telemedicine weekly, and 52% do so daily.

"Strong physician support for telemedicine underscores its increasing role in modern health care, with the potential to transform how care is delivered for years to come," Doximity said. 

Additionally, around two-thirds of physicians said that telehealth had "improved patient outcomes" in their practices, particularly among neurologists, endocrinologists and rheumatologists. Doximity found that endocrinologists, urologists, gastroenterologists, rheumatologists and neurologists were the top adopters of the technology, respectively. 

The most common use of telemedicine in clinical practice is for follow up visits, as 84% of doctors said they will use the technology to carry out those appointments. Next, 60% of physicians said they use telehealth for medication management, 57% said they use it to discuss lab reports or test results with patients and 52% said they use it to help patients manage chronic disease.  

Half of the doctors surveyed said telemedicine had improved patients' adherence to treatment plans, up from 37% last year. 

Nearly one-third of physicians said the technology has helped them serve more patients per day, and two-thirds said it has helped them better treat their patients. 

Read the full report from Doximity here.

Feel free to send any tips, suggestions, story ideas and data to Ashley at ashley.capoot@nbcuni.com.