NEW YORK – Molecular Templates on Thursday began treating patients with advanced solid tumors in a Phase I trial of MT-8421, a CTLA-4-targeted therapy.
The trial is enrolling several cohorts of solid tumor patients with cancer types that often have an immune rich tumor microenvironment, including those with microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) cancers. These include melanoma, hepatocellular carcinoma, non-small cell lung cancer, renal cell carcinoma, mesothelioma, esophageal cancer, head and neck cancer, urothelial carcinoma, and cervical carcinoma.
The dose escalation portion of the study will enroll between 24 and 30 patients. The trial will explore the engineered toxin body drug MT-8421 as a monotherapy and in combination with Bristol Myers Squibb's Opdivo (nivolumab) in these patient populations. It will evaluate the safety, tolerability, and preliminary efficacy of the treatment as well as its pharmacokinetics and pharmacodynamics.
MT-8421 is Molecular Templates' third engineered toxin body candidate to enter clinical studies. The firm is also developing a CD38-targeted drug, MT-0169, in patients with extramedullary myeloma and an anti-PD-L1 therapy, MT-6402, in patients with PD-L1-positive solid tumors. In 2021, MT-6402 was granted fast track designation by the US Food and Drug Administration for the treatment of patients with advanced non-small cell lung cancer expressing PD-L1.