Early outcomes from lutetium Lu-177 vipivotide tetraxetan treatment in patients selected for therapy with piflufolastat F-18 PET imaging.

Abstract

191 Background: The Vision trial utilized Ga 68 PSMA 11 imaging to select patients for treatment with Lutetium Lu 177 Vipivotide Tetraxetan. Current guidelines allow not only Ga 68 PSMA 11 PET but also Piflufolastat F 18 PET when selecting patients for Lutetium Lu 177 Vipivotide Tetraxetan but little is published on outcomes to this approach. Methods: Patients were enrolled on an IRB approved managed access protocol and were treated by a single investigator at a single institution. Eligible patients had mCRPC and had received previous treatment with at least one androgen receptor pathway inhibitor and at least one round of taxane based chemotherapy. Baseline imaging, demographics, treatment history, and tumor characteristics were collected. Patients were treated with 7.4 GBq of Lutetium Lu 177 Vipivotide Tetraxetan every 6 weeks for up to six cycles. Adverse events and PSA response were collected. Results: Fourteen patients were enrolled between August 2021 and August 2022. All patients had advanced mCRPC, were heavily pre-treated, and had failed both hormonal as well as chemotherapeutic options. The average number of androgen receptor pathway inhibitor courses for the cohort is 2.4 (range 1-4) and the average number of taxane courses for the cohort is 1.5 (Range 1-3). 11 patients underwent Piflufolastat F 18 PET and 3 patients had Ga 68 PSMA 11 PET. Baseline PSA varied significantly from 2.51 - 961.71 ng/mL. Declines of 50% in PSA were observed in 8/14 patients. 2 patients had greater than 80% PSA reductions. Conclusions: PSA treatment responses were similar to those reported in the Vision trial in this cohort of patients selected with either Piflufolastat F 18 PET or Ga 68 PSMA 11 PET supporting the guideline recommendations. Clinical trial information: NCT04825652 .