Imugene Ltd (ASX:IMU, OTC:IUGNF) will showcase new data from its Neo-POLEM Phase II trial, investigating its PD1-Vaxx immunotherapy program in early-stage colorectal cancer, at this week’s European Society for Medical Oncology (ESMO) Congress 2025 in Berlin — one of the world’s leading forums for cancer research and innovation.
The company’s abstract, “Phase II trial of neoadjuvant PD-1 vaccine PD1-Vaxx in operable MSI-high colorectal cancer,” has been accepted for e-poster presentation at the five-day congress, which attracts more than 30,000 clinicians, researchers and industry specialists from around the world. The presentation will be delivered by Dr Tony Dhillon of the Royal Surrey NHS Foundation Trust in the UK.
Managing director and CEO Leslie Chong said the recognition reflected PD1-Vaxx’s growing international profile.
“We are delighted to see PD1-Vaxx recognised with presentation at the ESMO Congress, highlighting its growing international clinical footprint,” Chong said. “The Neo-POLEM study marks an important expansion of our PD1-Vaxx program into early-stage colorectal cancer, an area where improved treatment options remain urgently needed.”
Expanding PD1-Vaxx into colorectal cancer
The accepted abstract outlines the design of the Neo-POLEM Phase II trial, an investigator-initiated study coordinated by the Southampton Clinical Trials Unit in the UK in partnership with the Australasian Gastro Intestinal Trials Group (AGITG) and funded by Imugene. Recruitment began in May 2025 and is now open across several Australian sites, with UK site activation under way.
The single-arm Bayesian optimal design study will enrol 44 patients with operable stage II–III microsatellite-instability-high (MSI-H) or mismatch-repair-deficient (dMMR) colon cancer, who will receive three PD1-Vaxx vaccinations over six weeks before surgery. After resection, adjuvant therapy will be selected by investigators according to standard protocols.
The primary endpoint is major pathological response (MPR) — defined as ≤10% viable tumour cells at surgery — while secondary measures include safety, response rate, disease-free and overall survival, and surgical outcomes. Exploratory work will analyse molecular and immune correlates of response and resistance using tumour and blood samples.
Novel vaccine approach to checkpoint inhibition
PD1-Vaxx is Imugene’s B-cell peptide vaccine designed to induce a polyclonal antibody response against the immune checkpoint protein PD-1. Unlike established monoclonal antibody checkpoint inhibitors such as nivolumab, pembrolizumab and ipilimumab, which are administered intravenously, PD1-Vaxx aims to stimulate patients’ own immune systems to generate similar — or potentially stronger — anti-PD-1 activity with a more convenient vaccine dosing schedule and improved safety profile.
MSI-H colorectal tumours are known for their high mutation burden and strong immune infiltration, features that make them particularly responsive to immune-based therapies.
Broader pipeline
PD1-Vaxx is one of several candidates in Imugene’s growing immuno-oncology portfolio, which also includes the CD19-targeting CAR T therapy azer-cel for blood cancers and the oncolytic virotherapy platform CF33 for solid tumours. Across these programs, the company aims to harness patients’ immune systems to deliver durable anti-cancer responses with potentially improved safety and cost efficiency.
Imugene’s e-poster presentation is available here at the company's website.