FDA Approves Clinical Trials for MT-125, a Promising Glioblastoma Drug

On July 1, 2025, scientists at The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology announced the FDA's approval for their experimental drug MT-125 to enter clinical trials. This innovative treatment aims to enhance the sensitivity of glioblastoma tumors to both radiation and chemotherapy while preventing the cancer's invasive capabilities. Glioblastoma, a particularly aggressive form of brain cancer, affects approximately 14,000 individuals annually in the United States, with a dismal average survival rate of just 14 to 16 months.

**Significance of MT-125**

Currently, standard treatment for glioblastoma involves a combination of surgery, radiation, and chemotherapy. However, half of glioblastoma patients exhibit a subtype that remains resistant to traditional treatments, highlighting the urgent need for new therapeutic options. "We know glioblastoma patients are awaiting a breakthrough, and we are moving as fast as humanly possible," stated Dr. Courtney Miller, a professor and academic affairs director at The Wertheim UF Scripps Institute and a member of the University of Florida Health Cancer Center.

The development of MT-125 stems from years of research focusing on myosin motors, nanoscale proteins that play critical roles in cellular movement and connectivity. Dr. Miller and her team designed a spectrum of drug candidates aimed at inhibiting these myosin motors in various contexts. In a study published on July 1 in the journal *Cell*, they reported that MT-125 significantly alters the behavior of glioblastoma cells, making them more susceptible to radiation therapy. The drug also encourages the formation of multinucleated cells that are more prone to cell death, effectively stunting tumor growth.

**Collaborative Efforts Across Institutions**

To validate the oncological potential of MT-125, the research team collaborated with Dr. Steven Rosenfeld, a neuro-oncologist at the Mayo Clinic in Jacksonville, Florida. Their partnership has led to promising results in preclinical settings. "We found in mice that combining MT-125 with a number of kinase inhibitors created long periods of a disease-free state that we haven’t seen in these mouse models before," Dr. Rosenfeld stated.

Despite these promising results, the researchers remain cautious about the transition from animal studies to human trials. "Many potential drugs that perform well in mice fail in human studies due to biological differences," Dr. Rosenfeld emphasized. Researchers also expressed concerns about toxicity, although they noted that MT-125 appears to target cancer cells while sparing healthy cells. The proposed administration method involves pulsed doses of the drug, minimizing potential side effects.

**Funding and Future Directions**

MT-125 has been licensed to Myosin Therapeutics, a biotechnology company founded by the scientists involved in its development. They are set to kick off first-in-human clinical trials within the year, pending the release of a federal grant that has already received internal approval. Funding for the study has been provided by the National Institutes of Health and the William Potter Glioblastoma Research Fund, established in memory of William Potter.

Dr. Miller also indicated that MT-125 may hold promise beyond glioblastoma, potentially benefiting patients with malignant gliomas and other cancer types. Concurrently, she and her collaborators are preparing a clinical trial for another related compound, MT-110, which has shown potential in blocking drug cravings for methamphetamine use disorder.

**Conclusion**

The approval of MT-125 for clinical trials represents a significant advancement in the ongoing battle against glioblastoma. As researchers continue to explore the drug's efficacy and safety, the medical community remains hopeful for a breakthrough that could alter the treatment landscape for one of the most challenging cancers. With ongoing studies and collaborative efforts, the future may hold new hope for patients facing this devastating diagnosis.

**References**: Radnai, L., Young, E.J., Kikuti, C., et al. (2025). Development of clinically viable non-muscle myosin II small molecule inhibitors. *Cell*. DOI: 10.1016/j.cell.2025.06.006.