Immuneering Reports 94% Six-Month Survival Rate in Phase 2a Pancreatic Cancer Study

Immuneering has reported a six-month overall survival (OS) rate of 94% in a phase 2a clinical trial evaluating its MEK inhibitor, atebimetinib, in patients with first-line pancreatic cancer. Based on these results, the company is preparing to initiate a pivotal trial aimed at securing accelerated approval.
The study involved 34 participants who received atebimetinib along with a modified regimen of the gemcitabine–nab-paclitaxel chemotherapy combination. This chemotherapy regimen is currently used in the treatment of pancreatic cancer.
Because the trial did not include a control arm, Immuneering compared the observed survival outcomes to those reported in a 2013 study involving a full dose and schedule of the same chemotherapy combination. That earlier study recorded a six-month survival rate of 67%, with a median OS of 8.5 months. At the time of data cutoff in Immuneering’s trial, the median OS had not yet been reached.
Progression-free survival (PFS) at six months was 72% in the atebimetinib group, in contrast to 44% in the historical chemotherapy study. The trial had not yet reached its median PFS duration. The overall response rate was 39%, which compares to 23% in the historical control group.

Speaking on a call with investors, Immuneering CEO Ben Zeskind, Ph.D., discussed the interim results, highlighting tumor response and continued shrinkage. “The vast majority of tumors are continuing to shrink,” Zeskind said. He noted that the data did not suggest an increase in disease progression or survival events and expressed confidence in the continued performance of the treatment.
Adverse event data from the atebimetinib study were presented in comparison with three pancreatic cancer pivotal trials for other drugs. Grade 3 or higher anemia was more frequently observed in the atebimetinib group than in those trials. However, other severe adverse events were less common. One patient in the Immuneering study experienced grade 3 or worse vomiting. No patients reported grade 3 or worse diarrhea or nausea.
Immuneering identified a lower occurrence of rash, nausea, vomiting, and diarrhea in its study as areas in which atebimetinib may differ from other MAP kinase pathway-targeting drugs.

When asked to compare the study outcomes with other investigational therapies, including Revolution Medicines’ daraxonrasib, Zeskind stated that those data pertain to second-line treatment. He also noted that other drug candidates have not yet demonstrated compatibility with chemotherapy. He expressed confidence in atebimetinib’s role in the first-line setting regardless of potential competitors.
Following the announcement of the trial results, Immuneering’s stock opened down 6% at $2.22. The company currently has a market capitalization of under $100 million and reported $35.9 million in cash as of the end of March. It previously stated that its available funds are expected to sustain operations into next year.