Key Takeaways

  • Both remigromig doses achieved noninferior BCVA gains compared with monthly ranibizumab at 1 year in the pivotal BRUNELLO trial

  • PDR-related adverse events and treatment discontinuations were more frequent with remigromig, warranting further safety evaluation

  • Remigromig targets the Wnt pathway, offering a potential alternative mechanism for DME treatment, with additional pivotal data anticipated from BAROLO

Merck announced 1-year results from the pivotal phase 2b/3 BRUNELLO trial evaluating remigromig (MK-3000), an investigational Wnt pathway agonist for diabetic macular edema (DME). Findings were presented at the American Academy of Ophthalmology (AAO) 2026 annual meeting in New Orleans.

Both remigromig doses met the primary endpoint of noninferiority to monthly ranibizumab 0.5 mg in mean change from baseline in best-corrected visual acuity (BCVA) at week 52. Mean BCVA gains were 9.1 letters with remigromig 0.5 mg and 8.7 letters with remigromig 0.8 mg, compared with 11.8 letters for ranibizumab. Neither remigromig dose demonstrated superiority on secondary endpoints.

Safety findings identified higher rates of proliferative diabetic retinopathy (PDR)-related adverse events with remigromig. These occurred in 6.7% and 6.1% of patients receiving remigromig 0.5 mg and 0.8 mg, respectively, compared with 0.9% receiving ranibizumab. Treatment discontinuations due to adverse events were also higher with remigromig (4.9% and 4.5% versus 0.9%).

Merck reported that PDR cases were generally manageable with standard treatment and that additional safety analyses are ongoing.

Remigromig is a tetravalent, tri-specific antibody designed to activate the Wnt pathway, which contributes to blood-retinal barrier maintenance and repair. Its mechanism differs from anti-VEGF therapies that directly inhibit vascular endothelial growth factor.

The randomized, double-masked BRUNELLO trial enrolled 984 adults with DME who received monthly intravitreal injections during the first year. Treatment frequency will transition to personalized intervals during the second year.

Merck plans to discuss the findings with regulatory authorities. Remigromig is also being evaluated in the pivotal phase 2b/3 BAROLO trial for DME and the phase 2 SUPER TUSCAN study for wet age-related macular degeneration and retinal vein occlusion.