SABRE: Assessment of safety and efficacy of 64Cu-SAR-BBN in patients with PSMA-negative biochemical recurrent prostate cancer.

Authors

Luke Nordquist

Luke T. Nordquist

Urology Cancer Center, PC, Omaha, NE

Luke T. Nordquist , Eva Lengyelova , Andrei Iagaru , Brandon Robert Mancini , Hong Song , Medhat Osman , David Josephson , Frankis Almaguel , Daniel Saltzstein , Michelle Parker , Robert M. Miller , Neal D. Shore

Organizations

Urology Cancer Center, PC, Omaha, NE, Clarity Pharmaceuticals, Eveleigh, NSW, Australia, Stanford University, Stanford, CA, BAMF Health, Grand Rapids, MI, SSM Health St. Louis University Hospital, St. Louis, MO, Tower Urology, Los Angeles, CA, Loma Linda University Cancer Center, Loma Linda, CA, Urology San Antonio, San Antonio, TX, Carolina Urologic Research Center, Myrtle Beach, SC

Research Funding

Clarity Pharmaceuticals

Background: Between 20-40% of patients with prostate cancer (PC) will relapse within 10 years of their primary PC treatment, as identified through rising prostate-specific antigen (PSA) levels. Early diagnosis of biochemical recurrence (BCR) with accurate staging is essential to informing optimal treatment decision-making. Approximately 20% of biochemically recurrent PC patients show low or no PSMA expression on prostate-specific membrane antigen (PSMA)-targeted PET. Consequently, these patients are unlikely to benefit from PSMA-targeted agents and represent a significant unmet need for both imaging and therapy. The Gastrin Releasing Peptide receptor (GRPr) is a transmembrane G-protein coupled receptor that is upregulated in many human cancers, including PC. 64Cu-SAR-BBN, a GRPr-targeting agent, uses a radioactive form of copper, copper-64 (64Cu), to image cancers using PET. Initial clinical data have shown that 64Cu-SAR-BBN was able to detect lesions in 32% (8/25) of patients with BCR of PC and negative/equivocal PSMA PET. Methods: SABRE is a phase II, single arm, non-randomized, open-label study of 64Cu-SAR-BBN administered to patients with BCR of PC following definitive therapy. Key eligibility criteria include confirmed adenocarcinoma of the prostate, recurrence of PC based on rising PSA after definitive therapy and negative or equivocal findings for PC on an approved PSMA PET. Approximately 50 patients will be enrolled. The objectives are to assess the safety of 64Cu-SAR-BBN (200 MBq), and its ability to detect recurrent PC when traditional PSMA PET is not informative. Patients will complete a PET/CT on the same day (1 to 4 hours) and the next day (24 ±6 hours) post-dose. We hypothesize that delayed imaging may allow the detection of additional lesions compared to the scan performed on the same day of the administration of the product. The safety endpoint includes the incidence and severity of treatment-emergent adverse events and serious adverse events following the administration of 64Cu-SAR-BBN. Efficacy endpoints include correct detection rate (participant level) and positive predictive value (at participant and region level) at each scan timepoint independently. The 64Cu-SAR-BBN PET/CT scans will be assessed centrally by 3 independent, blinded readers. Each reader will evaluate the scans for the presence of pathological 64Cu-SAR-BBN uptake in the prostate bed/gland, pelvic lymph nodes (LN), extra pelvic LN, visceral/soft tissue and bone regions. Patients will be followed for up to 180 days to verify the findings. The 64Cu-SAR-BBN PET/CT results will then be assessed against a composite Reference Standard (histopathology, conventional imaging, and/or PSA levels) determined by an independent, blinded, central expert panel. 50% recruitment was reached on July 24, 2023. Clinical trial information: NCT05407311.

Disclaimer

This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org

Abstract Details

Meeting

2024 ASCO Genitourinary Cancers Symposium

Session Type

Trials in Progress Poster Session

Session Title

Trials in Progress Poster Session A: Prostate Cancer

Track

Prostate Cancer - Advanced,Prostate Cancer - Localized

Sub Track

Diagnostics and Imaging

Clinical Trial Registration Number

NCT05407311

Citation

J Clin Oncol 42, 2024 (suppl 4; abstr TPS346)

DOI

10.1200/JCO.2024.42.4_suppl.TPS346

Abstract #

TPS346

Poster Bd #

Q20

Abstract Disclosures

Similar Abstracts

Abstract

2024 ASCO Genitourinary Cancers Symposium

Utility of PSMA PET/CT for imaging ductal carcinoma of the prostate.

First Author: Ahmed M. Mahmoud

First Author: Jose Mauricio Mota

First Author: Edward Maldonado