SCOTTSDALE, Ariz. — April 29, 2025 — HonorHealth Research Institute recently treated the first patient in a 50-site international clinical trial that will test a new type of therapy aimed at difficult-to-treat melanoma, an aggressive type of skin cancer.
This new therapy targets PRAME, a peptide commonly found in melanoma tumors. The therapy uses the patient's own manufactured and enhanced immune system T cells to create billions of new patient specific cells to attack melanoma, even after the cancer has spread to other parts of the body.
"We are excited about the potential of this new type of cellular therapy," said Justin Moser, M.D., an associate clinical investigator in the Research Institute's Cancer Research Division.
"Patients with advanced stage melanoma that has spread to other parts of the body, and who have exhausted other possibilities, might now have new options, giving them and their loved ones renewed hope," said Dr. Moser, who also is an associate research professor at Arizona State University's new School of Medicine and Advanced Medical Engineering.
Called SUPRAME, this clinical trial of nearly 360 patients will test an engineered T cell receptor (TCR), T cell therapy, called ACTengine® designed by Immatics, a clinical-stage biotechnology company located in Houston, Texas. Also known as IMA203 TCR-T, this is the world's first TCR therapeutic targeting PRAME.
T cells from the patient's blood are removed and re-engineered in a laboratory to target the specific patient's cancer cells that contain PRAME. These new customized cells are then multiplied by the billions and infused back into the patient to hunt down and destroy the cancer. The therapy requires only one dose. Please see: https://www.youtube.com/watch?v=a7fk6EZbu5o
Results published in Nature Medicine
This Phase III trial is based on a Phase I trial of patients in which the engineered cells were shown to be safe and effective, with minimal side effects. Initial study results were published April 9 in the scientific journal Nature Medicine:
"Here we report a non-prespecified interim analysis of IMA203, an autologous TCR T product targeting a PRAME-derived peptide presented by HLA-A*02:01, in a first-in-human dose-escalation trial (NCT03686124)," according to the published paper, "Autologous T cell therapy for PRAME+ advanced solid tumors in HLA-A*02+ patients: a phase 1 trial."
Results from the early phase clinical trial showed a response rate of 54%, with a median duration of response of more than 1 year. A subgroup of 12 out of 26 patients showed a more than 50% reduction of tumor lesions and a median progression free survival of 13.4 months.
In addition, unlike some cell therapies, the turn-around time for manufacturing the ACTengine modified T cells and returning them to the patient is only approximately 2 weeks.
"We are tremendously grateful for all the dedicated professionals at clinical institutions in the United States and Europe who support us in our mission of delivering the power of T cells to patients with cancer," said Cedrik Britten, Immatics' Chief Medical Officer.
