Analysts were keen to see a new modality compete with Roche’s approved drug Lucentis in the late-stage trial but new safety issues could complicate the future for Merck’s candidate.
Merck’s diabetic macular edema candidate improved vision on par with Roche’s VEGF inhibitor Lucentis but new safety signals that drove a higher rate of discontinuations in the trial raised concern among analysts.
“Today’s update is not enough to establish a differentiated profile for Merck’s novel Wnt-pathway agonist,” BMO Capital Markets wrote Thursday morning.
Remigromig, which is a new mechanism of action for the eye condition, showed non-inferiority to Lucentis in correcting vision for both doses tested in the Phase 2b/3 trial dubbed BRUNELLO, Merck said in a Thursday release. Change in best-corrected visual acuity (BCVA) from baseline to week 52 was the main goal of the trial.
But in the treatment arm, Merck flagged higher rates of proliferative diabetic retinopathy (PDR) and vitreous hemorrhage, or bleeding inside the eye’s vitreous region that can lead to sudden vision changes, as well as treatment discontinuations, as compared with those who received Lucentis.
Nevertheless, Merck said remigromig was “generally well tolerated” in the study. The company did not provide specific results but promised to reveal more at the American Academy of Ophthalmology Annual Meeting in October.
Analysts at Guggenheim were impressed by the result, the first time a novel mechanism of action has matched the VEGF inhibitor Lucentis in a clinical trial, according to the analyst on Thursday morning. But the side effects were concerning.
BMO, on the other hand, said the side effects and the lack of detailed data “could limit our enthusiasm” on the readout.
“Additional clarity on efficacy is needed,” BMO added.
That said, remigromig is not a major catalyst for investors as Merck works to build its post-Keytruda future, Guggenheim wrote. “We believe from a Merck perspective investors’ expectations for remigromig have been relatively limited.”
Investors are more closely watching the upcoming European Society for Medical Oncology (ESMO) Meeting next month for details on two key oncology assets: the Moderna-partnered mRNA cancer vaccine called intismeran autogene and the Kelun-Biotech–partnered ADC sacituzumab tirumotecan (sac-TMT). Merck will be hosting an investor event to coincide with the conference.
BMO, meanwhile, is eyeing multiple upcoming readouts for the TL1A targeting antibody tulisokibart, including in ulcerative colitis and hidradenitis suppurativa.
“We believe these catalysts among other pipeline assets provide several opportunities for Merck to demonstrate progress toward diversifying its growth profile ahead of Keytruda’s loss of exclusivity,” BMO said.
Remigromig came to Merck through the up to $3 billion acquisition of EyeBio in 2024, which continues to operate as a wholly owned subsidiary. The unit brought Merck back into the ophthalmology space.
The drug is a tetravalent, trispecific antibody designed to repair and maintain the blood-retinal barrier, Merck explained. The company is also testing the therapy, which is delivered by an injection into the eye, in neovascular age-related macular degeneration.
The BRUNELLO trial enrolled 984 patients who received one of two doses of remigromig or Lucentis.
