Immuneering’s investigational pancreatic cancer drug provided patients in a mid-stage trial with nearly nine additional months of survival, according to results presented at the American Society of Clinical Oncology annual meeting on June 1. The Phase 2a study evaluated the MEK-targeting deep cyclic inhibitor atebimetinib combined with modified gemcitabine/nab-paclitaxel (mGnP) in patients with first-line metastatic pancreatic cancer.
The combination therapy achieved a median overall survival of 17.3 months, compared to 8.5 months for patients treated with gemcitabine/nab-paclitaxel alone as reported in the pivotal Phase 3 MPACT study. Median progression-free survival was recorded at 8.3 months, and the disease control rate reached 82%. The confirmed overall response rate stood at 36%. These results were based on data from 55 patients who received atebimetinib plus mGnP.
Ben Zeskind, CEO of Immuneering, said, “We kind of have cancer surrounded. Those RAS inhibitors are making a really good attack from the second line direction. We think 17.3 months is a really compelling median overall survival coming from the first-line direction.” Zeskind also highlighted that results were consistent across cohorts and spoke to “the robustness of the data.”
Meredith Pelster, associate director of gastrointestinal cancer research at Sarah Cannon Research Institute and an investigator on the trial, said tolerability was notable: “With the modified gemcitabine/nab-paclitaxel schedule, I’m not having to deal with the degree of cytopenias I typically would, and then the addition of atebimetinib, really we’re not seeing high-grade toxicity at all . . . . Keeping these patients on treatment is not challenging.”
Zeskind further commented that maintaining tolerability is key for both quality and duration of life: “It used to be really that patients had to choose between survival and tolerability...and I think the possibility that these data raise is that patients may have to make fewer trade-offs.” In Immuneering’s trial, he noted that 84% of participants maintained or gained weight after three months.
Despite positive clinical outcomes reported by Immuneering on May 21 and expanded upon during ASCO presentations Monday, company shares declined nearly 24% by mid-afternoon Eastern time. Mizuho analysts described this drop as overdone and attributed it primarily to a slight decrease in overall response rate rather than concerns about efficacy or safety.
Immuneering plans to begin dosing for its Phase 3 MAPKeeper 301 trial around mid-year with enrollment expected for approximately 510 patients; topline results are anticipated by mid-2028.
