Patients taking weight-loss and diabetes drugs Wegovy and Ozempic have an increased risk of developing a rare eye condition that could lead to loss of vision, a European Medicines Agency (EMA) committee announced Friday.

The EMA’s drug safety committee (PRAC) launched a review of medicines containing semaglutide — a GLP-1 agonist and the active ingredient in Novo Nordisk’s Ozempic, Wegovy and Rybelsus — in January, following concerns that the drugs could lead to an increased risk of developing non-arteritic anterior ischemic optic neuropathy (NAION).

NAION is a disorder caused by reduced blood flow to the optic nerve in the eye, which can damage the nerve and lead to permanent vision loss.

PRAC said it found that the condition is “a very rare side effect” of semaglutide, potentially affecting up to one in 10,000 people taking the drug. The EMA said that exposure to semaglutide in people with diabetes is linked to a twofold increase in the risk of developing NAION compared with people not taking the medicine.

The regulator has requested that the product information for semaglutide medicines is updated to include NAION as a side effect with a frequency of “very rare.” The final decision needs sign off from the European Commission.