NEW YORK – Fusion Pharmaceuticals said on Thursday that it has partnered with Merck on a clinical trial evaluating the combination of Fusion's targeted radiotherapy, FPI-1434, and pembrolizumab (Merck's Keytruda) for patients with solid tumors expressing insulin-like growth factor 1 receptor (IGF-1R).
The companies will partner on a Phase I/II clinical trial to evaluate the safety, tolerability and pharmacokinetics of FPI-1434 plus the PD-1 inhibitor pembrolizumab. FPI-1434 is a radio-immunoconjugate therapy designed to deliver alpha-emitting isotopes to tumor cells expressing IGF-1R. Fusion describes this as "targeted alpha therapy," or "TAT," which combines an alpha particle-emitting isotope with antibodies and other targeted molecules and is designed to deliver the therapeutic payloads to specific tumor cells expressing the target.
According to Fusion, the trial of the combination regimen will begin about six-to-nine months after a recommended Phase II dose is established in a trial investigating FPI-1434 monotherapy. Under the terms of the partnership, Fusion will sponsor the trial and Merck will supply pembrolizumab.
"With our strong preclinical data demonstrating promising activity with FPI-1434 and immuno-oncology agents, we believe we have an opportunity to improve efficacy in tumor indications where Keytruda is approved, and to potentially expand into new tumor indications," Fusion CEO John Valliant said in a statement. "This collaboration with Merck builds off our research on the mechanism of action of alpha radiation and aligns with our goal to expand the utility of radiopharmaceutical therapies, including advancing into earlier lines of cancer therapy."