Phase 3 Trial: Xaluritamig (AMG 509) Plus Abiraterone in mCRPC

A large international Phase 3 clinical trial  is evaluating a new treatment combination for men with metastatic castration-resistant prostate cancer (mCRPC) who have not yet undergone chemotherapy (in castration resistant settings, prior chemo is allowed). The study is testing xaluritamig (AMG 509) together with abiraterone acetate against the investigator’s choice of standard therapies (docetaxel, cabazitaxel, or abiraterone alone) in an open-label, randomized design that will enroll about 750 participants. The primary goal is to determine whether the combination improves overall survival compared to current treatment options, with additional measures expected to include disease progression, PSA response, safety, and quality of life.

Xaluritamig is currently being evaluated in five additional clinical trials across both castration-resistant and hormone-sensitive prostate cancer settings, exploring its potential in a range of disease stages.

Xaluritamig is an advanced bispecific T-cell engager designed to connect the immune system’s CD3 receptors with STEAP1, a protein expressed on more than 95% of prostate tumors. This link activates T-cells to identify and destroy cancer cells, offering a precision-driven immunotherapy approach. Abiraterone, already a standard therapy, inhibits androgen synthesis through CYP17 blockade. Together, the two agents combine immune activation with hormonal suppression, two critical pathways in prostate cancer progression.

This combination is designed for patients who have developed resistance to androgen deprivation therapy but remain chemotherapy-naive, a population with limited options. By targeting both the immune system and androgen signaling, researchers hope to delay disease progression and extend survival before chemotherapy becomes necessary.

The xaluritamig–abiraterone pairing follows encouraging trends in prostate cancer research, where combination strategies are showing increasing promise.

Clinical trial.