NEW YORK – Convergent Therapeutics on Tuesday said it will evaluate CONV 01-alpha, a prostate-specific membrane antigen-directed antibody paired with the alpha particle emitter actinium-225, in combination with Point Biopharma's PSMA radioligand PNT2002 linked to a beta particle emitter lutetium-177 in advanced castration-resistant prostate cancer patients.
The drugmakers are evaluating CONV 01-alpha and PNT2002 in a Phase I/II trial that has already begun enrolling patients at Weill Cornell Medicine. Investigators will enroll up to 33 patients with metastatic castration-resistant prostate cancer that is PSMA-positive by PET imaging. Patients must have progressive disease despite prior treatment with an androgen receptor signaling inhibitor and taxane chemotherapy.
In the Phase I dose-escalation portion, researchers will establish the maximum tolerated dose for CONV 01-alpha, which patients will receive in combination with a dose of PNT2002 that Point established in another ongoing trial, called SPLASH. Then, in the Phase II expansion portion, researchers will track the number of patients who after receiving the combination regimen experience more than a 50 percent decline in prostate-specific antigen levels.
The strategy to couple an antibody with ligand-targeted treatments evolved from research conducted at Weill Cornell Medicine and patented by Cornell University, which Cambridge, Massachusetts-based Convergent exclusively licensed.
"Within the field, there is significant and growing interest in our differentiated approach that leverages the complementary advantages of co-targeting surface cancer molecules such as PSMA with both antibodies and small molecule ligands, as well as alpha and beta radiopharmaceuticals," Convergent CEO Philip Kantoff said in a statement. "This collaboration with Point Biopharma will, therefore, help to facilitate and validate our disruptive strategy of combining radioligands and antibodies carrying different payloads, directed at a cancer target, in order to significantly improve the efficacy of radiopharmaceutical therapies."
Indianapolis-based Point, meanwhile, is studying PNT2002 in the Phase III SPLASH trial in PSMA-expressing, metastatic castration-resistant prostate cancer patients who have progressed on androgen receptor signaling inhibitors or can't receive chemotherapy. The company will enroll 400 patients in the next portion of this randomized trial, which is slated to readout in mid-2023.