Merck Reports One-Year BRUNELLO Data for Remigromig in Diabetic Macular Edema
Merck presented one-year results from the Phase 2b/3 BRUNELLO trial of remigromig in adults with diabetic macular edema at AAO 2026. Both doses met the primary vision endpoint, showing non-inferiority to ranibizumab, but secondary endpoints did not show superiority and adverse-event discontinuations were higher than with ranibizumab. The investigational therapy is a tri-specific antibody that aims to activate the Wnt pathway.
Merck shared 12-month data from the BRUNELLO Phase 2b/3 study of remigromig (MK-3000) in diabetic macular edema at AAO 2026. The trial compared two remigromig doses with monthly ranibizumab 0.5 mg. Both doses achieved the primary best-corrected visual acuity endpoint, meeting predefined non-inferiority criteria; no secondary endpoint showed superiority.
Remigromig is an investigational tetravalent tri-specific antibody intended to activate the Wnt pathway. In the study, proliferative diabetic retinopathy-related adverse events and adverse-event discontinuations occurred more often in remigromig arms than with ranibizumab. Merck said further analyses are ongoing, and PDR cases were generally manageable with standard care.
If approved, a new mechanism could broaden options for DME patients, especially those with persistent disease after anti-VEGF therapy. Higher PDR-related events and discontinuations may temper clinician adoption and require monitoring. For Merck, mixed secondary results may shape investor expectations, while payers could weigh cost and safety against existing therapies.