The National Comprehensive Cancer Network (NCCN) and the Society of Nuclear Medicine and Molecular Imaging (SNMMI) guidelines now include the use of piflufolastat F 18 (Pylarify), along with all approved PSMA-PET imaging agents, for the selection of prostate cancer patients to receive PSMA-targeted radioligand therapy.1
“We are pleased that the NCCN and SNMMI have now both updated their guidelines to include Pylarify, the most widely adopted PSMA PET imaging agent, for patient selection for PSMA-targeted lutetium radioligand therapy,” Bela Denes, MD, vice president of Medical Affairs at Lantheus, the developer of piflufolastat F 18, stated in a news release. “We believe this will increase the accessibility to PSMA-targeted therapeutics for patients with advanced disease and further validates the benefit and utility that Pylarify provides to the US prostate cancer community.”
FDA approval of piflufolastat F18
The FDA approved the PSMA-PET imaging agent piflufolastat F18 (previously also known as 18F-DCFPyL and PyL) in 2021 for identifying suspected metastasis or recurrence of prostate cancer.2 The approval was supported in large part by findings from the phase 3 CONDOR trial, in which 63.9% of men with biochemically recurrent prostate cancer who had no evidence of disease on standard-of-care imaging had a change in intended management after their 18F-DCFPyL–PET/CT scan.3
The multicenter phase study enrolled men with rising PSA after definitive therapy and negative or equivocal standard-of-care imaging. Patients were required to have a PSA level ≥0.2 if they had undergone radical prostatectomy or a PSA level ≥2.0 if they were treated with radiation therapy or cryotherapy.
The primary end point was correct localization rate (CLR), defined as percentage of patients with a 1:1 correspondence between at least 1 lesion identified by PyL–PET/CT and the composite standard of truth (pathology, correlative imaging, or PSA response). PyL scans were read by 3 blinded independent central readers.
Overall, there were 208 evaluable patients, about 85% of whom underwent RP, either alone or with radiation. Median PSA level of the cohort was 0.8 ng/mL, and 68.8% had a PSA level <2.0 ng/mL. Some 27.9% had received at least 1 prior systemic therapy.
Detection of disease as manifested by a positive 18F-DCFPyL–PET/CT scan was 65.9%, 59.6%, and 59.1% by the 3 readers.
The prespecified criterion for CLR success was for the lower limit of the 95% CI to exceed 20% for at least 2 of the 3 readers. For every reader, the lower bound of the 95% CI for the CLR was well in excess of the 20% benchmark, meeting the primary end point of the study.
The CLRs were 85.6% (95% CI, 78.8%-92.3%), 87.0% (95% CI, 80.4%-93.6%), and 84.8% (95% CI, 77.8%-91.9%) by the 3 readers. Some 64% of the evaluable patients had a change in intended management due to the scan.
1.Lantheus Announces Updates to the NCCN Guidelines for PSMA PET Imaging for Prostate Cancer. Published online May 11, 2022. Accessed May 11, 2022. https://bit.ly/37AfuHO.
2. Lantheus Receives U.S. FDA Approval of PYLARIFY® (piflufolastat F 18) Injection, the First and Only Commercially Available PSMA PET Imaging Agent for Prostate Cancer. Published online May 27, 2021. Accessed May 27, 2021. https://bwnews.pr/3vtMgBh.
3. Morris MJ, Rowe SP, Gorin MA, et al. Diagnostic performance of 18F-DCFPyL-PET/CT in men with biochemically recurrent prostate cancer: results from the CONDOR phase 3, multicenter study [published online before print February 26, 2021.] doi: 10.1158/1078-0432.CCR-20-4573