Apellis Pharmaceuticals' Syfovre, after achieving the first FDA approval for advanced eye disease geographic atrophy, has been associated with rare but severe side effects, according to the American Society of Retinal Specialists (ASRS).The group issued a letter to doctors Saturday flagging cases of eye inflammation and six reports of occlusive retinal vasculitis in patients who took the drug, BioPharma Dive reported. The condition is a type of inflammation that blocks blood flow to the retina and could potentially cause blindness.ASRS didn’t tie the safety issues to a specific batch of product but noted that the side effects began one to two weeks after a patient’s first Syfovre injection. The organization urged vigilance and close follow-up after administration, according to the news outlet.

The news caused Apellis’ stock price to sink nearly 32% to $52.62 by Monday afternoon.

The company puts the Syfovre-associated retinal vasculitis rates at 0.01% per injection, making for a real-world safety profile that matches up with its clinical studies, an Apellis spokesperson told Fierce Pharma over email. No such instances were reported in the drug’s pivotal phase 3 studies, according to the spokesperson.

“We are in the process of thoroughly investigating all cases with external experts, including real-world procedure technique and potential risk factors,” the spokesperson added. “Patient safety is our top priority, and we take any adverse event seriously.”

Evaluate Pharma previously pegged Syfovre to reach $2.6 billion in sales by 2028. The drug slows growth of a marker of disease progression as opposed to improving or stalling central vision loss. Its approval was the culmination of four years of “intense” work on the launch, co-founder and CEO Cedric Francois, M.D., Ph.D., told Fierce Pharma in an interview ahead of Syfovre’s approval. It was the first launch in an area many have tried, and failed, to target in recent years.

Similar warnings from ASRS have made waves in the past. In 2020, the group alerted members about 14 cases of retinal vasculitis in patients after taking Novartis’ wet age-related macular degeneration drug Beovu. After a promising initial rollout, this news caused a 5.5% decline in the company's shares and resulted in a 15% surge in shares for its competitor, Regeneron. One doctor even told Fierce Pharma over email that he quit the med following the news.

Source: fiercePharma.com