A Phase 1b, Open-Label, Multicenter Study Evaluating the Safety, Tolerability, and Feasibility of Neoadjuvant Xaluritamig Therapy Prior to Radical Prostatectomy in Subjects With Newly Diagnosed Localized Intermediate or High-Risk Prostate Cancer

Inclusion Criteria: Participants are eligible to be included in the study only if all the following criteria apply: * Participants planned to undergo radical prostatectomy. * Histologically or cytologically confirmed adenocarcinoma of the prostate at initial biopsy, without neuroendocrine differentiation, signet cell, or small cell features. Intermediate- or high-risk localized prostate cancer, defined as: * Gleason score of 4+3 or higher AND initial PSA (iPSA) \>10 OR * Clinically advanced (cT3) on Magnetic Resonance Imaging (MRI) obtained within 3 months prior to screening AND/OR * Positive locoregional lymph nodes as detected by prostate-specific membrane antigen-positron emission tomography (PSMA-PET) scans OR ≤ 5 local lymph nodes on MRI can be enrolled. * Participants must have undergone a PSMA-PET (CT or MRI) scan within 3 months prior to screening as part of the standard of care (SOC). * Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1. Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply: * Prior treatment for participant's prostate cancer. \- Exception: Participants intended for enrollment in cohort B may have received an oral GnRH antagonist up to 3 months prior to the start of screening. * Any evidence of metastases outside of the surgical resection field identified by conventional imaging or PSMA-PET scans. * Confirmed history or current autoimmune disease or other diseases resulting in permanent immunosuppression or requiring permanent immunosuppressive therapy. * Participants with symptoms and/or clinical signs and/or radiographic signs that indicate an acute and/or uncontrolled active systemic infection within 7 days prior to the first dose of study treatment: \- Participant has known active infection requiring antibiotic treatment. Upon completion of antibiotics and resolution of symptoms, the participant may be considered eligible for the study from an infection standpoint. * Recent history of arterial or venous thrombosis (eg, stroke, transient ischemic attack, pulmonary embolism, or deep vein thrombosis) within 6 and 3 months prior to the first dose of study treatment, respectively. Note: Participants with a history of venous thrombosis must be on stable anti-coagulation. * Myocardial infarction and/or symptomatic congestive heart failure (New York Heart Association ≥ class II) within 12 months of first dose of xaluritamig with the exception of ischemia or non-ST segment elevation myocardial infarction controlled with stent placement more than 6 months prior to first dose of xaluritamig. * Requirement for chronic systemic corticosteroid therapy unless stopped (with adequate tapering) within 7 days prior to dosing. * Currently receiving treatment in another investigational device or drug study, or less than 4 weeks (since ending treatment on another investigational device or drug study\[ies\]). Other investigational procedures and participation in observational research studies while participating in this study are excluded with the exception of investigational scans.