Merck’s Eye Disease Drug Candidate Meets Trial Goal, Showing Potential of $3 Billion Acquisition

A drug candidate for diabetic macular edema (DME) acquired by Merck in a deal worth about $3 billion met its primary endpoint in a clinical trial.

According to Fierce Biotech on the 24th (local time), Merck met the primary endpoint in the phase 2b/3 Brunello trial of remigromig, a DME treatment candidate. The trial compared remigromig with ranibizumab, which Roche subsidiary Genentech sells in the United States as Lucentis.

Remigromig mimics norrin, a natural ligand, to activate the Wnt signaling pathway. The pathway is known to help restore and maintain the blood-retinal barrier.

Results showed that both doses of remigromig demonstrated noninferiority to ranibizumab on the primary endpoint, which assessed change in best-corrected visual acuity at week 52.

Merck said remigromig was well tolerated. However, rates of proliferative diabetic retinopathy, vitreous hemorrhage and treatment discontinuation due to adverse events were higher than with ranibizumab. Merck is analyzing the results.

Merck plans to present the trial data at the American Academy of Ophthalmology’s annual meeting next month and to discuss the results with regulatory authorities. Another phase 2b/3 trial of remigromig in DME is underway, with primary completion targeted for March next year.

At a Wells Fargo event this month, analyst Mohit Bansal asked whether Merck was “going after the weakest drug” and whether it could demonstrate superiority to ranibizumab in the Brunello trial. Lucentis competes in the DME market with Regeneron’s Eylea and Roche’s Vabysmo, among others.

In response, Dean Li, head of Merck Research Laboratories, said 30% to 40% of patients do not respond to existing vascular endothelial growth factor (VEGF) drugs or stop responding, and explained that remigromig could offer an option that uses a different pathway.

In 2024, Merck acquired EyeBio for $1.3 billion upfront, gaining remigromig and the bispecific antibody MK-8748. The deal includes up to an additional $1.7 billion in milestone payments. These assets are part of Merck’s strategy to secure growth drivers after Keytruda’s patent expiration.