Immuneering Highlights 64% 12-Month Survival in Phase 2A Pancreatic Cancer Study, Eyes Phase 3

Key Points

• In a 34‑patient Phase 2A cohort, atebumetanib plus modified gemcitabine/nab‑paclitaxel achieved a 64% 12‑month overall survival with median OS not reached at a 13.4‑month follow‑up, and secondary endpoints outperformed MPACT benchmarks (PFS 8.5 vs 5.5 months; ORR 39% vs 23%; DCR 81% vs 48%).
• Immuneering plans a global pivotal Phase 3, MapKeeper 301, enrolling ~510 patients with overall survival as the primary endpoint, aiming to dose the first patient mid‑2026 and report top‑line results mid‑2028, and will report OS from an expanded >50‑patient cohort in H1 2026.
• Tolerability was described as manageable — only Grade 3 anemia and neutropenia exceeded 10% and were attributed to chemotherapy — and the company says it has a cash runway into 2029 to fund the pivotal program and additional studies.

Immuneering NASDAQ: IMRX provided an update from its ongoing Phase 2A trial of atebumetanib plus modified gemcitabine and nab-paclitaxel in first-line metastatic pancreatic cancer patients, highlighting a positive 12-month overall survival (OS) landmark and outlining plans for a pivotal Phase 3 program. The company hosted the conference call on January 7, 2026.

Phase 2A: 12-month overall survival and follow-up

Chief Executive Officer Benjamin Zeskind said the company’s 12-month OS rate in the Phase 2A cohort of 34 first-line pancreatic cancer patients treated with atebumetanib plus modified gemcitabine and nab-paclitaxel was 64%. Zeskind emphasized that median OS has not been reached and noted a median follow-up time of 13.4 months.

Management compared the Phase 2A results to historical benchmarks for gemcitabine plus nab-paclitaxel (GNP) from the MPACT study, stating that 12-month OS in MPACT was approximately 35%, versus 64% in Immuneering’s study. Zeskind also referenced cross-trial comparisons to other first-line regimens that are generally used in younger, fitter patients due to toxicity, citing approximately 48% 12-month OS for FOLFIRINOX and approximately 45% for NALIRIFOX, compared with 64% for atebumetanib plus chemotherapy in the Phase 2A trial.

The company also highlighted what it described as consistency in separation from historical GNP benchmarks over time, citing a 27-point gap at six months, a 36-point gap at nine months, and a 29-point gap at 12 months. Zeskind added that OS remained 64% out to the 13.4-month median follow-up, while the company cited an approximately 31% OS benchmark for standard of care at that timepoint.

Secondary efficacy endpoints and patient population

Beyond OS, Zeskind presented secondary endpoints versus MPACT historical benchmarks:

• Median progression-free survival (PFS): 8.5 months (vs. 5.5 months benchmark)
• Overall response rate (ORR): 39% (vs. 23% benchmark)
• Disease control rate (DCR): 81% (vs. 48% benchmark)

Management also pointed to baseline demographics, stating that patients in the Phase 2A study were generally well-matched to prior pivotal trials but were “meaningfully older,” with a median age of 69 and more than two-thirds over age 65.

Safety and tolerability observations

On safety, Zeskind said tolerability remained a differentiator for atebumetanib. The company stated that only two categories of Grade 3 adverse events occurred in more than 10% of patients: anemia and neutropenia, which management characterized as well-known side effects of chemotherapy. The company added that these had not been observed with atebumetanib monotherapy.

Quality of life case study and patient experience

In prepared remarks, management framed quality of life as a key theme alongside survival. Guest speaker Dr. Meredith Pelster of Sarah Cannon Research Institute, an investigator in Immuneering’s Phase 2A study, described a patient from the expanded enrollment group (not part of the original 34-patient cohort) receiving daily atebumetanib plus modified gemcitabine and nab-paclitaxel in the first line.

According to Pelster, the patient was a 64-year-old female with metastatic pancreatic cancer with a KRAS G12V mutation. She had approximately 8.8 centimeters of baseline tumor burden across four target lesions (two in the liver, one in the pancreas, and one in the peritoneum). Pelster reported that by the first scan, both liver metastases were “rendered undetectable” and remained undetectable across two subsequent scans, while the remaining lesions were described as generally stable, resulting in a net reduction of “slightly more than” 30% in the sum of target lesion diameters (a partial response).

Pelster also reported a CA19-9 decline from 30,000 to “well below” 5,000, weight gain on study, few adverse events, and an improvement in the patient’s FAACT (Functional Assessment of Anorexia/Cachexia Therapy) score from 96 to 141. She described a shift from requiring significant family assistance due to pain and weakness at study start to being able to drive independently.

Phase 3 plan: MapKeeper 301 and upcoming milestones

Zeskind outlined the planned pivotal Phase 3 trial, MapKeeper 301, which he described as a global randomized study in metastatic first-line pancreatic cancer. The trial is expected to enroll approximately 510 patients randomized to atebumetanib plus modified gemcitabine and nab-paclitaxel versus standard gemcitabine and nab-paclitaxel alone, with overall survival as the primary endpoint. Management said the company aligned with the FDA and EMA on the trial design in the fourth quarter of 2025, expects to dose the first patient in the middle of 2026, and anticipates top-line results in mid-2028.

The company also said it plans to report OS from an expanded cohort of over 50 patients in the first half of 2026, consisting of the original 34 plus an additional roughly 20 patients, and stated that OS in the expanded cohort is “trending consistently” with the original dataset. Management also cited additional upcoming milestones including circulating tumor DNA analyses and the start of Phase 2 combination studies in non-small cell lung cancer beginning in 2026.

On the financial side, Zeskind stated the company has a cash runway into 2029 following a September financing, which he said would fund the company through the pivotal data readout and initiation of additional trials.

About Immuneering NASDAQ: IMRX

Immuneering Nasdaq: IMRX is a clinical-stage biopharmaceutical company leveraging artificial intelligence and its proprietary RABIT (Repurposing and Accelerating Biotechnology Tools) platform to design and optimize small-molecule and peptide therapies. By analyzing large-scale biomedical datasets, Immuneering's machine learning algorithms identify novel drug–target interactions, repurpose existing drug scaffolds and accelerate lead candidate selection. The company's AI-driven approach aims to reduce development timelines and improve therapeutic profiles in areas of high unmet medical need.

The company's lead program, IRX-2, is a small-molecule candidate currently in Phase 2 clinical trials for the treatment of painful diabetic peripheral neuropathy.