Diagnostic Performance of 18F-DCFPyL-PET/CT in Men with Biochemically Recurrent Prostate Cancer: Results from the CONDOR Phase III, Multicenter Study

Michael J Morris, Steven P Rowe, Michael A Gorin, Lawrence Saperstein, Frédéric Pouliot, David Josephson, Jeffrey Y C Wong, Austin R Pantel, Steve Y Cho, Kenneth L Gage, Morand Piert, Andrei Iagaru, Janet H Pollard, Vivien Wong, Jessica Jensen, Tess Lin, Nancy Stambler, Peter R Carroll, Barry A Siegel, CONDOR Study Group, Michael Morris, Andreas Wibmer, Jeremy Durack, Steve Solomon, Michael Gorin, Rana Harb, Darko Pucar, Preston Sprenkle, Frédéric Pouliot, Jean-Mathieu Beauregard, Alexis Beaulieu, François-Alexandre Buteau, Jeffrey Wong, David Yamauchi, Scott Glaser, Tanya Dorff, Austin Pantel, Vivek Narayan, Matthew Fillare, Erin Schubert, Steve Cho, Greg Cooley, Zachary Morris, Monica Langeland, Kenneth Gage, Julio Pow-Sang, Kosj Yamoah, Morand Piert, Ajjai Alva, Zachary Reichert, Daniel Spratt, Andrei Iagaru, Guido Davidzon, Carina Mari, Farshad Moradi, Janet Pollard, Chad Tracy, Peter Carroll, Spencer Behr, Hao Nguyen, Jeffrey Simko, Barry Siegel, Jack Jennings, Jeff Michalski, Russell Pachynski, Michael J Morris, Steven P Rowe, Michael A Gorin, Lawrence Saperstein, Frédéric Pouliot, David Josephson, Jeffrey Y C Wong, Austin R Pantel, Steve Y Cho, Kenneth L Gage, Morand Piert, Andrei Iagaru, Janet H Pollard, Vivien Wong, Jessica Jensen, Tess Lin, Nancy Stambler, Peter R Carroll, Barry A Siegel, CONDOR Study Group, Michael Morris, Andreas Wibmer, Jeremy Durack, Steve Solomon, Michael Gorin, Rana Harb, Darko Pucar, Preston Sprenkle, Frédéric Pouliot, Jean-Mathieu Beauregard, Alexis Beaulieu, François-Alexandre Buteau, Jeffrey Wong, David Yamauchi, Scott Glaser, Tanya Dorff, Austin Pantel, Vivek Narayan, Matthew Fillare, Erin Schubert, Steve Cho, Greg Cooley, Zachary Morris, Monica Langeland, Kenneth Gage, Julio Pow-Sang, Kosj Yamoah, Morand Piert, Ajjai Alva, Zachary Reichert, Daniel Spratt, Andrei Iagaru, Guido Davidzon, Carina Mari, Farshad Moradi, Janet Pollard, Chad Tracy, Peter Carroll, Spencer Behr, Hao Nguyen, Jeffrey Simko, Barry Siegel, Jack Jennings, Jeff Michalski, Russell Pachynski

Abstract

Purpose: Current FDA-approved imaging modalities are inadequate for localizing prostate cancer biochemical recurrence (BCR). 18F-DCFPyL is a highly selective, small-molecule prostate-specific membrane antigen-targeted PET radiotracer. CONDOR was a prospective study designed to determine the performance of 18F-DCFPyL-PET/CT in patients with BCR and uninformative standard imaging.

Experimental design: Men with rising PSA ≥0.2 ng/mL after prostatectomy or ≥2 ng/mL above nadir after radiotherapy were eligible. The primary endpoint was correct localization rate (CLR), defined as positive predictive value with an additional requirement of anatomic lesion colocalization between 18F-DCFPyL-PET/CT and a composite standard of truth (SOT). The SOT consisted of, in descending priority (i) histopathology, (ii) subsequent correlative imaging findings, or (iii) post-radiation PSA response. The trial was considered a success if the lower bound of the 95% confidence interval (CI) for CLR exceeded 20% for two of three 18F-DCFPyL-PET/CT readers. Secondary endpoints included change in intended management and safety.

Results: A total of 208 men with a median baseline PSA of 0.8 ng/mL (range: 0.2-98.4 ng/mL) underwent 18F-DCFPyL-PET/CT. The CLR was 84.8%-87.0% (lower bound of 95% CI: 77.8-80.4). A total of 63.9% of evaluable patients had a change in intended management after 18F-DCFPyL-PET/CT. The disease detection rate was 59% to 66% (at least one lesion detected per patient by 18F-DCFPyL-PET/CT by central readers).

Conclusions: Performance of 18F-DCFPyL-PET/CT achieved the study's primary endpoint, demonstrating disease localization in the setting of negative standard imaging and providing clinically meaningful and actionable information. These data further support the utility of 18F-DCFPyL-PET/CT to localize disease in men with recurrent prostate cancer.See related commentary by True and Chen, p. 3512.