Data from The MATTERS Trial: Safety and Tolerability of Whole-Body Hyperthermia at 41.50°C in Combination with Chemotherapy in Metastatic Cancer Patients

AbstractPurpose: Whole-body hyperthermia (WBHT) is a promising therapy for advanced malignancies, including metastatic pancreatic ductal adenocarcinoma (PDAC). This first-in-human study evaluated the safety and tolerability of repeated WBHT sessions at 41.50°C for various treatment durations and in combination with standard-of-care chemotherapy regimens. Patients and Methods: Twelve patients with advanced solid tumors, primarily metastatic PDAC, completed the study. WBHT was administered using an innovative medical device (TempoCure, ElmediX) as monotherapy or with standard-of-care chemotherapy in escalating durations of 2, 4, and 6 hours, in four cohorts. Safety was assessed through adverse event (AE) monitoring, serious AE (SAE) reporting, and comprehensive clinical and laboratory evaluations up to a 10-week follow-up. Tolerability was evaluated according to whether patients were able to complete all planned WBHT cycles, with or without concomitant chemotherapy, without the need for dose modifications or treatment interruptions. Results: The WBHT treatment was well tolerated, with most patients completing scheduled treatments despite advanced disease. The most frequent AEs were fatigue, hypokalemia, nausea, and diarrhea. Initial decubitus ulcers led to improved patient handling protocols. No clear increase in AE or SAE incidence was associated with longer WBHT durations or chemotherapy combination. The trend toward fewer AEs in later treatments likely reflects a procedural learning curve. Conclusions: WBHT administered with the TempoCure system at 41.50°C for 2, 4, and 6 hours is safe and tolerable alone or in combination with chemotherapy, in patients with advanced cancer refractory to prior treatments. These findings support further investigation in upcoming randomized trials designed to evaluate efficacy in metastatic PDAC. Significance: The MATTERS trial demonstrates that WBHT at 41.50°C, delivered with the TempoCure device, is a safe and well-tolerated treatment for advanced malignancies, particularly in patients with refractory metastatic PDAC. These findings support the integration of WBHT with standard chemotherapy regimens, paving the way for future efficacy trials aimed at improving therapeutic outcomes in challenging cancer populations.