Abstract LB-90: DUPA-99mTc localizes to prostate cancer in men with locally advanced and metastatic disease.

Abstract

Abstract Objectives: Currently, the absence of an effective prostate cancer targeted imaging agent limits the ability to correctly clinically stage prostate cancer. The conjugation of a high affinity PSMA-targeting ligand, 2-[3-(1, 3-dicarboxy propyl)-ureido] pentanedioic acid (DUPA) to technetium 99m (99mTc) has generated a new prostate cancer imaging agent termed DUPA-99mTc. The objective of this phase 0 clinical trial was to confirm the preclinical data demonstrating high affinity localization to human prostate cancer cells and tissues. Methods: Nine men with advanced and metastatic prostate cancer confirmed by CT scan and/or bone scan were enrolled in the Phase 0 trial to investigate both the biologic efficacy and toxicity of the DUPA-99mTc agent. Dosimetry studies of images, blood and urine at 5 and 20 mCi doses were obtained at baseline, 5 min, 1, 2, 4, 8 and 24 hours. Results: Nine men with documented prostate cancer were enrolled. Seven of the nine subjects were evaluable. One patient did not receive a full iv dose and another received poorly labeled DUPA-99mTc (70%). The remaining seven patients, who received DUPA-99mTc in excess of 95% labeled product, demonstrated localization to all cancerous areas seen on pre-enrollment images (CT and Bone Scans) plus additional lesions in several of the patients. Two men who had biopsy-confirmed locally recurrent prostate cancer had scans prior to resection, and tissue was monitored intra-operatively and ex-vivo to confirm the higher 99mTc counts in malignant tissue compared to normal tissue. No significant toxicity was demonstrated with administration of the DUPA-99mTc in any subject. Conclusions: DUPA-99mTc compound can be reliably administered to men with prostate cancer without toxicities and with equal or superior imaging compared to conventional CT and bone scans. A Phase I/II trial will be conducted to confirm the performance of this imaging agent in a larger patient population. Citation Format: Thomas A. Gardner, James W. Fletcher, Song-Chu Ko, Philip S. Low, Timothy L. Ratliff. DUPA-99mTc localizes to prostate cancer in men with locally advanced and metastatic disease. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-90. doi:10.1158/1538-7445.AM2013-LB-90