Immatics Initiates Phase 1/2 Clinical Trial to Evaluate PRAME TCR Bispecific IMA402 in Patients with Advanced Solid Tumors

• TCER IMA402 is the first next-generation, half-life extended TCR Bispecific targeting PRAME to enter the clinic
• Patient enrollment for IMA402 Phase 1/2 trial underway
• The trial will evaluate safety, tolerability, and anti-tumor activity of IMA402 in patients with recurrent and/or refractory solid tumors
• First clinical data expected in 2024  

Tuebingen, Germany and Houston, Texas, August 10, 2023 – Immatics N.V. (NASDAQ: IMTX, “Immatics”), a clinical-stage biopharmaceutical company active in the discovery and development of T cell-redirecting cancer immunotherapies, today 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.

“The addition of IMA402 to our clinical pipeline is a truly exciting step and aligns with our strategic goal to harness the full potential of PRAME, one of the most promising cancer targets in solid tumors. With our half-life extended format, we believe IMA402 has the potential to be an attractive treatment option by enhancing efficacy, minimizing toxicities, and providing favorable dosing regimen for cancer patients.,” said Cedrik Britten, Chief Medical Officer at Immatics. “We are working with urgency to bring IMA402 to a broad patient population as quickly as possible and look forward to sharing first clinical data in 2024.”

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 of accelerating 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.