A Study of Xaluritamig Plus Abiraterone Versus Investigator's Choice in Participants With Chemotherapy-naïve Metastatic Castration-resistant Prostate Cancer

Must have received: androgen receptor pathway inhibitor (enzalutamide, apalutamide, darolutamide)

Prior disease progression on 1, and only 1, androgen receptor pathway inhibitor (ARPI) (either enzalutamide, apalutamide, or darolutamide) is required.

Must have received: orchiectomy and/or ongoing androgen-deprivation therapy

Participants must have had prior orchiectomy and/or ongoing androgen-deprivation therapy (ADT) and a castrate level of serum testosterone (< 50 ng/dL or < 1.7 nmol/L).

Cannot have received: STEAP1-targeted therapy

Prior six transmembrane epithelial antigen of the prostate 1 (STEAP1)-targeted therapy.

Cannot have received: abiraterone (abiraterone)

Exception: Prior disease progression on or intolerance to abiraterone

Prior disease progression on or intolerance to abiraterone.

Cannot have received: chemotherapy

Exception: in the mCRPC setting

Prior treatment with any chemotherapy regimen in the mCRPC setting

Cannot have received: docetaxel (docetaxel)

Exception: > 6 cycles in the mHSPC setting

Prior treatment with ... > 6 cycles of docetaxel treatment in the mHSPC setting.

Cannot have received: anticancer therapy, immunotherapy, or investigational agent

Exception: ARPIs (enzalutamide, darolutamide, apalutamide): minimum washout of 2 weeks prior to the first dose; androgen suppression therapy permitted

Any anticancer therapy, immunotherapy, or investigational agent within 4 weeks before first dose of study treatment with the following exceptions: Androgen receptor pathway inhibitors (ARPIs; enzalutamide, darolutamide, apalutamide): minimum washout of 2 weeks prior to the first dose of study treatment. Androgen suppression therapy (eg, luteinizing hormone-releasing hormone/gonadotrophin releasing hormone [LHRH/GnRH] analogue [agonist/antagonist]) is permitted.

Cannot have received: radioligand therapy

Exception: within 8 weeks of first dose

Prior radioligand therapy (RLT) within 8 weeks of first dose of study treatment.

Cannot have received: radionuclide therapy (radium-223)

Exception: within 2 months of first dose

Prior radionuclide therapy (radium-223) within 2 months of first dose of study treatment.

Cannot have received: palliative radiotherapy

Exception: within 2 weeks before first dose

Prior palliative radiotherapy within 2 weeks before first dose of study treatment. Participants must have recovered from all radiation-related toxicities.

Cannot have received: cytotoxic chemotherapy

Exception: concurrent

Concurrent cytotoxic chemotherapy

Cannot have received: androgen receptor pathway inhibitor (enzalutamide, darolutamide, apalutamide)

Exception: concurrent

Concurrent ... ARPI

Cannot have received: immunotherapy

Exception: concurrent

Concurrent ... immunotherapy

Cannot have received: radioligand therapy

Exception: concurrent

Concurrent ... RLT

Cannot have received: PARP inhibitor

Exception: concurrent

Concurrent ... poly adenosine diphosphate ribose polymerase (PARP) inhibitor

Cannot have received: biological therapy

Exception: concurrent

Concurrent ... biological therapy

Cannot have received: investigational therapy

Exception: concurrent

Concurrent ... investigational therapy

Cannot have received: CD3-directed therapy

Prior CD3-directed therapy.