Evaluation of Xaluritamig in High-Risk, Biochemically Recurrent, Non-metastatic Castrate-sensitive Prostate Cancer

A Phase 1b, Open-label, Multicenter Study Evaluating the Safety, Tolerability, and Efficacy of Xaluritamig in Subjects With High-risk Biochemical Recurrence of Nonmetastatic Castration-sensitive Prostate Cancer After Definitive Therapy

The main objective of this study is to evaluate the safety and tolerability of xaluritamig monotherapy in adult participants with high-risk biochemical recurrent (BCR) nonmetastatic castration-sensitive prostate cancer (nmCSPC).

Study Overview

• Status: Active, not recruiting
• Conditions: Prostate Cancer; High-risk Biochemical Recurrence; High Risk Biochemical Recurrence of Non-metastatic Castration-sensitive Prostate Cancer; Non-metastatic Castration-sensitive Prostate Cancer
• Intervention / Treatment: Drug: Xaluritamig

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Phase 1

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • Camperdown, New South Wales, Australia, 2050
      • Chris OBrien Lifehouse
  • Victoria
    • Malvern, Victoria, Australia, 3144
      • Cabrini Hospital
    • Melbourne, Victoria, Australia, 3000
      • Peter MacCallum Cancer Centre
• United States
  • Minnesota
    • Minneapolis, Minnesota, United States, 55455
      • University of Minnesota Medical Center Fairview
  • New York
    • New York, New York, United States, 10065
      • Memorial Sloan Kettering Cancer Center
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • University of North Carolina at Chapel Hill
    • Charlotte, North Carolina, United States, 28204
      • Levine Cancer Institute
  • Oregon
    • Portland, Oregon, United States, 97239
      • Oregon Health and Science University
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19107
      • Thomas Jefferson University
  • Texas
    • Dallas, Texas, United States, 75390
      • University of Texas Southwestern Medical Center
  • Washington
    • Seattle, Washington, United States, 98109
      • Fred Hutchinson Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria

• Histologically or cytologically confirmed adenocarcinoma of the prostate at initial biopsy, without neuroendocrine differentiation, signet cell, or small cell features.
• Prostate cancer initially treated by radical prostatectomy (RP) or radiotherapy (XRT) (including brachytherapy) or both (eg, salvage radiotherapy), with curative intent.
• PSA doubling time ≤ 12 months.
• Participants must have biochemically recurrent disease after definitive treatment to prostate by either RP or XRT.
• Screening PSA by the local laboratory ≥ 0.2 ng/mL for participants who had RP (with or without XRT) as primary treatment for prostate cancer or at least 2 ng/mL above the nadir (local assessments) for participants who had XRT or brachytherapy only as primary treatment for prostate cancer.
• Serum testosterone ≥ 150 ng/dL (5.2 nmol/L).
• Participants must have undergone a prostate-specific membrane antigen (PSMA) positron emission tomography (PET) scan during or within 3 months of screening.

Exclusion Criteria

• Present evidence of metastatic disease in conventional CT scan and/or bone scan
• Participants that present PSMA-positive lesions in the PSMA PET scan may be enrolled if the conventional imaging does not show suspicion of metastatic disease.

• Prior hormonal therapy, exceptions include:

  • Neoadjuvant/adjuvant therapy to treat prostate cancer ≤ 36 months in duration and ≥ 9 months before enrollment, or
  • A single dose or a short course (≤ 6 months) of hormonal therapy given for rising PSA ≥ 9 months before enrollment.
• Prior cytotoxic chemotherapy, aminoglutethimide, ketoconazole, abiraterone acetate, enzalutamide, apalutamide, or darolutamide for prostate cancer.
• Abiraterone acetate, enzalutamide, apalutamide, or darolutamide are allowed if administered in a neoadjuvant/adjuvant setting ≤ 36 months in duration and ≥ 9 months before enrollment.
• Prior systemic biologic therapy, including immunotherapy, for prostate cancer.
• If, in the investigator's opinion, salvage therapy is the preferred intervention.
• Autoimmune disease requiring systemic immunosuppression within the past 2 years.
• Participant 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.
• Requirement for chronic systemic corticosteroid therapy (prednisone dose > 10 mg/day or equivalent) or any other immunosuppressive therapies (including anti tumor necrosis factor alpha [TNFα] therapies) unless stopped (with adequate tapering) within 7 days prior to dosing.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Xaluritamig; Xaluritamig will be administered as a short-term intravenous (IV) infusion for a total of 6 cycles. One treatment cycle consists of 28 days for cycles 1-2 and 56 days for cycles 3-6.	Drug: Xaluritamig; IV infusion; Other Names: AMG 509

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)	Events categorized as adverse events (AEs) starting on or after first dose of investigational product (xaluritamig) as determined by the flag indicating if the AE started prior to the first dose on the Events Electronic Case Report Form (eCRF) and including 30 days after the last dose of investigational product (xaluritamig) or end of study date, whichever is earlier.	Up to approximately 2 years
Number of Participants Experiencing Treatment-related Adverse Events (TRAEs)	A TRAE is any TEAE that per investigators' review has a reasonable possibility of being caused by the investigational product (xaluritamig) determined by the flag indicating an event may have been caused by the investigational product (xaluritamig) on the Events eCRF. In the unlikely event that the flag is missing, the TEAE will be considered related.	Up to approximately 2 years

Secondary Outcome Measures

Outcome Measure	Time Frame
Time to Prostate-specific Antigen (PSA) Progression	Up to 50 months
Number of Participants With a PSA 50 Response	Up to approximately 50 months
Number of Participants With a PSA 90 Response	Up to approximately 50 months
Duration of PSA 50 Response	Up to approximately 50 months
Duration of PSA 90 Response	Up to approximately 50 months
Number of Participants With Undetectable PSA	Up to approximately 50 months
Time to Initiation of Androgen Deprivation Therapy or Androgen Receptor Directed Therapy	Up to approximately 50 months
Time to First use of new Anticancer Therapy	Up to approximately 50 months
Time to Metastatic Disease/Progression	Up to approximately 50 months
Metastasis-free Survival (MFS)	Up to approximately 50 months
Number of Participants Completing Xaluritamig Monotherapy Treatment	Up to approximately 24 months
Maximum Serum Concentration (Cmax) of Xaluritamig	Up to approximately 24 months
Time to Cmax (Tmax) of Xaluritamig	Up to approximately 24 months
Area Under the Concentration-time Curve (AUC) Over the Dosing Interval of Xaluritamig	Up to approximately 24 months
Terminal Half-life (t1/2) of Xaluritamig	Up to approximately 24 months

Collaborators and Investigators

• Sponsor: Amgen
• Investigators: Study Director: MD, Amgen

Publications and helpful links

Helpful Links

• AmgenTrials clinical trials website

Study record dates

Study Major Dates

• Study Start (Actual): September 23, 2024
• Primary Completion (Estimated): October 8, 2026
• Study Completion (Estimated): December 2, 2028

Study Registration Dates

• First Submitted: August 13, 2024
• First Submitted That Met QC Criteria: August 13, 2024
• First Posted (Actual): August 15, 2024

Study Record Updates

• Last Update Posted (Actual): January 26, 2026
• Last Update Submitted That Met QC Criteria: January 23, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Immunotherapy; STEAP1; Xaluritamig; T-Cell Engager; AMG509
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Prostatic Diseases; Male Urogenital Diseases; Prostatic Neoplasms
• Other Study ID Numbers: 20230238

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.
• IPD Sharing Time Frame: Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.
• IPD Sharing Access Criteria: Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No