UPDATE: CONVERGE-01 Trial Reports 83% PSA50 Response in Patients Without Prior Lu-PSMA

New results from the phase 2 CONVERGE-01 trial,  show preliminary antitumor activity of CONV01-α, an experimental PSMA-targeted alpha therapy, in patients with metastatic androgen pathway inhibitor-resistant prostate cancer (mCRPC) who had not previously received Lu-PSMA radioligand therapy.

CONV01-α, also known as ²²⁵Ac-rosopatamab tetraxetan, combines the alpha-emitting isotope actinium-225 with a monoclonal antibody targeting PSMA. Unlike small-molecule PSMA radioligands, this approach uses an antibody to deliver radiation to tumor cells.

Previous results from CONVERGE-01 demonstrated preliminary activity in patients previously treated with chemotherapy and Lu-PSMA. The new analysis focuses on Part 2, involving patients whose disease had progressed after at least one androgen receptor pathway inhibitor but who had not received Lu-PSMA or taxane chemotherapy for castration-resistant disease.

Nineteen patients received two administrations of CONV01-α, on days 1 and 15, at different dose levels.

Among 12 patients evaluable for PSA response, 83% (10/12) achieved a PSA reduction of at least 50%, while 25% (3/12) achieved a reduction of at least 90%. PSA50 responses occurred in all three evaluable patients receiving 45 kBq/kg and in seven of nine patients receiving the higher grouped dose levels.

The safety analysis identified hematological toxicity as an important concern. Grade 3–4 lymphopenia occurred in 45% of patients, while thrombocytopenia and neutropenia each occurred in 26%. No treatment discontinuations due to treatment-related adverse events were reported.

Dosimetry indicated radiation exposure to normal organs below published limits, including relatively low kidney exposure and no detectable activity in the salivary glands.

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