NCT06692959

A Phase II Trial of Neoadjuvant PD-1 Vaccine PD1-Vaxx in Operable MSI High Colorectal Cancer

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 44 (estimated)
• Sponsor: University of Southampton · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The aim of Neo-POLEM is to determine the rate of Major Pathological Response (MPR) of \<10% viable tumour cells after administering neoadjuvant PD-1 vaccine IMU-201 (PD1-Vaxx), as measured by percentage change pre- and post-treatment in operable MSI high CRC patients. All patients will be administered three doses of the PD1-Vaxx prior to resection surgery and will be followed up for a minimum of 2 years.

Detailed description

This is a phase II, Bayesian Optimal Design, single arm, one cohort, open label, multi-centre study of neoadjuvant PD-1 vaccine PD1-Vaxx and surgical resection in adult patients with operable MSI-high colorectal cancer. All patients will be administered PD1-Vaxx intramuscularly into the deltoid region of the upper arm on days 1,15 and 29. Patients will undergo resection surgery within 21 days, but up to 42 days of completing trial treatment. The resection sample will be examined locally for pathological response within 28 days of surgical resection. Patient will then remain in active follow up for up to 2 years. Once the last patient has completed their last visit a check will be made on all patients to confirm their recurrence and survival status. The aim of the trial is to determine the major pathological response rates after administering neoadjuvant PD-1 vaccine PD1-Vaxx in operable MSI-high CRC patients.

Conditions

• Colorectal Cancer

Interventions

Type	Name	Description
DRUG	PD-1 vaccine IMU-201 (PD1-Vaxx)	Investigational Medicinal Product (IMP) PD1-Vaxx is supplied as lyophilized drug substance APi2568, which is a B-cell epitope (amino acids 92-110 from PD-1) linked to a promiscuous T-cell epitope (amino acid residues 288-302 from measles virus fusion protein) via a 4-amino acid linker (G-P-S-L). IMU-201 is combined with water for Injection (WFI) and is emulsified with Montanide ISA 51 VG adjuvant to produce PD1-Vaxx.

Timeline

• Start date: 2025-06-16
• Primary completion: 2027-03-31
• Completion: 2029-01-31
• First posted: 2024-11-18
• Last updated: 2026-03-23

Locations

4 sites across 2 countries: Australia, United Kingdom