Regeneron Pharmaceuticals is closely watching new reports from doctors reporting that a small number of patients are experiencing unexplained and severe side effects with their drug, Eylea.
The best-selling drug, which is injected into the eye, is aimed at treating age-related macular degeneration and vision loss. Regeneron raked in $3.7 billion in sales from the treatment last year.
Now, a small number of patients have reported severe pain and vision loss after using the drug. Other clusters of similar outcomes have been reported in the past — at a rate of about 1 in 10,000 patients — and linked to inflammation. The company said that more reports could be popping up now as doctors now learn of the other cases.
Yet, one eye surgeon in Philadelphia reported that he was seeing a slight increase in the number of patients reporting the adverse effects.
The cases have reportedly come from various batches of the medicine, which has helped rule out the possibility of manufacturing defects.
For now, there’s been no formal recall of the drug and Regeneron is allowing patients reporting the side effects to receive a new dose of the medication.