Merck's remigromig matches ranibizumab in a 984-patient DME trial

Merck reported on 24 September 2026 that remigromig met the primary endpoint of BRUNELLO, a pivotal Phase 2b/3 trial in adults with diabetic macular edema, a leading cause of vision loss in people with diabetes. Remigromig is an investigational tetravalent, tri-specific antibody injected into the eye. It activates the Wnt signalling pathway to repair and maintain the blood-retinal barrier, a different mechanism from the anti-VEGF drugs that dominate the field.

The randomized, double-masked study (NCT06571045) enrolled 984 participants in three arms: remigromig at 0.5 mg or 0.8 mg, or 0.5 mg ranibizumab, dosed every four weeks in the first year. Both remigromig doses were non-inferior to ranibizumab on mean change in best-corrected visual acuity from baseline to week 52.

The remigromig arms also showed higher rates of proliferative diabetic retinopathy, vitreous hemorrhage and treatment discontinuations due to adverse events than the comparator, and Merck says further analyses are under way. Full year-one results are due at the American Academy of Ophthalmology annual meeting on 10 October 2026.