[18F]DCFPyL PET/CT versus [18F]fluoromethylcholine PET/CT in Biochemical Recurrence of Prostate Cancer (PYTHON): a prospective, open label, cross-over, comparative study

Purpose Primary objective was to compare the per-patient detection rates (DR) of [ 18 F]DCFPyL versus [ 18 F]fluoromethylcholine positron emission tomography/computed tomography (PET/CT), in patients with first prostate cancer (PCa) biochemical recurrence (BCR). Secondary endpoints included safety and impact on patient management (PM). Methods This was a prospective, open label, cross-over, comparative study with randomized treatment administration of [ 18 F]DCFPyL (investigational medicinal product) or [ 18 F]fluoromethylcholine (comparator). Men with rising prostate-specific antigen (PSA) after initial curative therapy were enrolled. [ 18 F]DCFPyL and [ 18 F]fluoromethylcholine PET/CTs were performed within a maximum time interval of 12 days. DR was defined as the percentage of positive PET/CT scans identified by 3 central imaging readers. PM was assessed by comparing the proposed pre-PET/CT treatment with the local treatment", defined after considering both PET/CTs. Results A total of 205 patients with first BCR after radical prostatectomy (73%; median PSA = 0.46 ng/ml [CI 0.16;27.0]) or radiation therapy (27%; median PSA = 4.23 ng/ml [CI 1.4;98.6]) underwent [ 18 F]DCFPyL- and/or [ 18 F]fluoromethylcholine -PET/CTs, between July and December 2020, at 22 European sites. 201 patients completed the study. The per-patient DR was significantly higher for [ 18 F]DCFPyL- compared to [ 18 F]fluoromethylcholine -PET/CTs (58% (117/201 patients) vs. 40% (81/201 patients), p