Immuneering (IMRX) Study Result summary

Study Design and Objectives

• IMM-1-104, a novel MEK inhibitor, was evaluated in a Phase 2a trial for pancreatic cancer, including monotherapy and combinations with modified gemcitabine/nab-paclitaxel and modified FOLFIRINOX.

• Over 75 pancreatic cancer patients were enrolled across all arms as of December 5, 2024.

• The study aims to expand MEK inhibitor use beyond BRAF to RAS-driven cancers and improve tolerability.

• The trial is supported by FDA Orphan Drug and Fast Track designations for pancreatic cancer and NRAS mutant melanoma.

• Additional Phase 2a combination arms and a pivotal global Phase 3 trial are planned for 2025.

Efficacy Results

• IMM-1-104 plus modified gemcitabine/nab-paclitaxel showed a 43% ORR, 86% DCR, and up to 14% CR in first-line pancreatic cancer, outperforming historical benchmarks.

• Combination with modified FOLFIRINOX led to a confirmed complete response with 100% reduction in target lesions.

• Monotherapy in second-line pancreatic cancer achieved up to 33% ORR, 52% DCR, and a 67% reduction in one patient.

• All evaluable patients in combination arms showed tumor size reductions, with deepening responses over time.

• Durable responses included >11 months stable disease in a third-line patient and median PFS of seven months among patients off treatment.

Safety and Tolerability

• IMM-1-104 demonstrated a highly differentiated safety profile, with no serious treatment-related adverse events in monotherapy or combination arms.

• In first-line combination with mGnP, grade 3-4 neutropenia was 10%, fatigue 0%, and diarrhea 5%.

• Most common TRAEs in monotherapy were mild to moderate and reversible; no Grade 3 or 4 TRAEs in more than 10% of patients.

• A patient in phase I remained on treatment for 11 months with improved quality of life and weight gain.

• The safety profile supports use in both monotherapy and combination regimens.