A box of Ozempic and its contents on a table in Dudley, North Tyneside, Britain, October 31, 2023.
George Fry | Reuters
Novo Nordisk investors appeared unfazed Thursday by a critical Harvard report linking the weight-loss drug to a rare eye condition.
Semaglutide, found in weight-loss drugs including Ozempic and Novo Nordisk's Wegovy, may be linked to an increased risk of a rare eye disease, according to a Harvard Medical School study.
Analysts said the study results were “not conclusive at all.” Shares in the Danish drugmaker were little changed on Thursday, falling in early morning trade before rising 0.1% by 11:17 a.m. London time.
The Harvard report found that patients with type 2 diabetes or obesity who were prescribed semaglutide were at increased risk of developing non-arteritic anterior ischemic optic neuropathy (NAION) — a condition that can lead to vision loss in one eye. The study found that patients were more likely to develop the eye condition than patients who were not prescribed the weight-loss drug.
While the research paper suggests “some association” with a rare eye event, the quality of the evidence is “very low, and the error bars are very wide,” according to Deutsche Bank analyst Emmanuel Papadakis.
The worst-case scenario, Papadakis said, might be an additional update to the warning section on drug labels, which is “not a radical change.”
He added that Deutsche Bank generally views semaglutide drugs as “one of the lowest-risk therapeutic classes in the history of the industry from a safety perspective.”
A Novo Nordisk spokesperson said NAION was not an “adverse drug reaction to marketed semaglutide” according to the approved labeling. They added that there were “major methodological limitations” to the study such as the “small number of subjects” with type 2 diabetes or obesity who were exposed to semaglutide and included in the trial.
“Patient safety is a top priority for Novo Nordisk, and we take all reports of adverse events resulting from the use of our medicines seriously,” a company spokesperson said.
The popularity of blockbuster drugs has made Novo Nordisk the most valuable company in Europe, with a valuation greater than Denmark's GDP last year.
Wegovy has been shown to have health benefits beyond weight loss and blood sugar regulation. In March, the FDA approved it for use in reducing the risk of heart disease.
But the drugs have come under scrutiny after some patients reported stomach pain and suicidal thoughts while taking them. A study by researchers at the University of British Columbia found an increased risk of intestinal obstruction, a disorder that prevents food from passing through the small or large intestine, and pancreatitis.
Drug labels already include warnings about pancreatitis and certain types of bowel obstruction. Vision changes are also listed as a possible side effect of both Ozempic and Wegovy.
The U.S. study, published Wednesday, analyzed data from 16,827 patients from December 2017 through November of last year. The researchers said more study is needed to assess whether semaglutide causes the eye condition.
CNBC's Jenny Reid contributed to this report.
