Immatics N.V. announced the initiation of a Phase 1/2 clinical trial with its proprietary Bispecific T cell engaging receptor (TCER®) IMA402. IMA402 is the second product candidate in Immatics? TCER® pipeline of next-generation, half-life extended bispecific molecules to enter clinical development.

It targets an HLA-A*02:01-presented peptide derived from PRAME, a clinically established cancer target frequently expressed in a large variety of solid tumors. The Phase 1/2 clinical trial (NCT05958121) investigates TCER® IMA402 in HLA-A*02:01-positive patients with PRAME-expressing recurrent and/or refractory solid tumors. The dose escalation part of the study is designed as a basket trial in focus indications to accelerate signal finding.

Initial focus indications are cutaneous and uveal melanoma, ovarian cancer, lung cancer, uterine cancer and synovial sarcoma, among others. Primary objectives of the IMA402 Phase 1/2 trial are to determine the maximum tolerated dose (MTD) and/or the recommended doses for trial extensions, as well as to characterize safety and tolerability of IMA402. Secondary objectives are to evaluate anti-tumor activity and assess pharmacokinetics of IMA402.

The Phase 1a dose escalation will be followed by a Phase 1b dose expansion, with the plan then to initiate a Phase 2 with indication-specific cohorts and/or combination therapies. Immatics has implemented an adaptive design for the dose escalation with the goal to accelerate the clinical development timeline of IMA402. Pharmacokinetics data will be assessed throughout the trial and might provide an early opportunity for adjustment of the treatment interval based on the half-life extended TCER® format.

The trial is initially planned to be conducted at approximately 15 sites in Europe, with extension into the US at dose expansion stage. The Phase 1a is designed to enroll approximately 45 patients. The trial initiation is based on the comprehensive preclinical studies with IMA402 presented at the European Society for Medical Oncology (ESMO) Congress 2022.

TCER® IMA402 is the second Immatics clinical program targeting PRAME, with the first being ACTengine® IMA203, a TCR-T cell therapy that is currently in Phase 1b dose expansion ? see recent data release. Both approaches, ACTengine® and TCER®, are distinct therapeutic modalities that the company believe have the potential to provide innovative treatment options for a variety of cancer patient populations with different medical needs.