Two TraCer PositROn EmiSSion Tomography ComBination for Efficacy EstimatiOn of Prostate Specific Membrane Antigen Radioligand Therapy in Patients With Metastatic Prostate Cancer (CROSSBOW)

Single-arm, open-label, phase II trial in 200 competent adult male patients with Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-3 and progressive metastatic prostate cancer, failing, failed, refused, not eligible for or no access to further approved lines of therapy. Patients will undergo sequential FDG positron emission tomography (PET) and 18F-DCFPyL PET to assess FDG/DCFPyL concordance fraction. Patients with DCFPyL/FDG concordance of 50% or greater will be treated with 131I-PSMA-1095 radioligand therapy (RLT). Best post-treatment serum prostate specific antigen response will be compared to concordance fraction.

Study Overview

• Status: Terminated
• Conditions: Prostatic Neoplasms; Prostate Cancer; Metastatic Prostate Cancer; Prostate Adenocarcinoma; Metastatic Prostatic Adenocarcinoma; Metastatic Prostate Carcinoma in the Soft Tissue
• Intervention / Treatment: Drug: 131I-PSMA-1095 Radioligand Therapy (RLT)

• Study Type: Interventional
• Enrollment (Actual): 11
• Phase: Phase 2

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Montreal, Quebec, Canada, H3T1E2
      • Stephan Probst

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male
• Age 18 years or older
• Documented metastatic adenocarcinoma of the prostate
• Under active medical oncology care
• ECOG performance status 0 - 3, inclusive
• Able to understand and provide written informed consent
• Able to tolerate the physical requirements of two PET/CT scans including lying for up to 30 minutes
• Progressive disease on any of: bone scan, CT, MRI or serum PSA as judged by the investigator
• Serum prostate specific antigen ≥ 1 ng/ml at baseline or CT/MRI soft-tissue measurable disease as per RECIST v1.1
• Failed, failing, refused, no access to or not eligible for any approved prostate cancer therapies including but not limited to: ADT, NAAD (e.g., abiraterone, enzalutamide, darolutamide or apalutamide), docetaxel, cabazitaxel, radium-223 and oligometastatic RTX
• Life expectancy of at least 3 months as judged by the investigator

Exclusion Criteria:

• Medically unstable (e.g. acute cardiac or respiratory distress or hypotensive)
• Exceeding the weight limit of the PET/CT bed (approximately 400 lbs.) or who cannot fit through the PET/CT bore (approximately 70 cm diameter)
• Unmanageable claustrophobia
• Prior failure of PSMA RLT
• Prior hemi-body irradiation

• Impaired organ function as evidenced by any of the following laboratory values:

  • Absolute neutrophil count < 1.5 x109/L
  • Platelet count < 75 x109/L
  • Hemoglobin < 85 g/L
  • Albumin < 2.5 g/dL (25 g/L)
  • Total bilirubin > 2 x ULN (unless in instances of Gilbert's disease)
  • AST or ALT > 2.5 x ULN (or > 5.0 x ULN in the presence of liver metastases)

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: 131I-PSMA-1095 Radioligand Therapy (RLT); Intravenous injection of 100 mCi of 131I-PSMA-1095 RLT, Q8 weeks up to a maximum of 4 doses	Drug: 131I-PSMA-1095 Radioligand Therapy (RLT); Intravenous injection of 100 mCi of 131I-PSMA-1095, Q8 weeks up to a maximum of 4 doses.; Other Names: PSMA RLT

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum prostate specific antigen (PSA)	The best serum prostate specific antigen (PSA) response will be calculated for each patient as: pre-treatment PSA minus lowest post-treatment PSA divided by pre-treatment PSA. Best PSA response will be reported as percent reduction (or increase) from baseline.	3 months post last dose of RLT

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse events	Frequency of adverse events in participants receiving therapy as per CTCAE v5.0	3 months post last dose of RLT

Collaborators and Investigators

• Sponsor: Sir Mortimer B. Davis - Jewish General Hospital

Study record dates

Study Major Dates

• Study Start (Actual): July 31, 2020
• Primary Completion (Actual): January 15, 2023
• Study Completion (Actual): January 15, 2023

Study Registration Dates

• First Submitted: September 8, 2019
• First Submitted That Met QC Criteria: September 10, 2019
• First Posted (Actual): September 11, 2019

Study Record Updates

• Last Update Posted (Actual): April 12, 2023
• Last Update Submitted That Met QC Criteria: April 10, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Keywords: PSMA; Radioligand therapy; PSMA therapy; 1095
• Additional Relevant MeSH Terms: Neoplasms by Histologic Type; Neoplasms; Urogenital Neoplasms; Neoplasms by Site; Carcinoma; Neoplasms, Glandular and Epithelial; Genital Neoplasms, Male; Prostatic Diseases; Prostatic Neoplasms; Adenocarcinoma
• Other Study ID Numbers: CROSSBOW

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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