Clinical experience with 225Ac-PSMA-617 TAT provided on an individual patient basis: a retrospective single-center multi-ethnics analysis of 232 patients.

Introduction: Since 2014 225Ac-PSMA-617 is offered as an unproven intervention in clinical practice on an individual patient basis to patients with advanced stage prostate cancer who had progressed under approved treatment lines. We here report 233 patients with in total 517 cycles of 225Ac-PSMA-TAT using different dosing schemes. Methods: Clinical data of 233 patients who had received 225Ac-PSMA-617 were retrospectively extracted from our medical files. 54 patients were excluded because their data were published previously. During time our clinical treatment protocol had changed because the initial dosing regimen translated into increased rates of xerostomia and a combination treatment of 225Ac/177Lu-PSMA-617 for each cycle was initiated. Clinical response by the anti-tumor activity of the different treatment strategies was evaluated by surrogate marker PSA at 8 and 16 weeks after the first cycle. Results: 104 patients retrospectively received a therapy of 7 ± 1 MBq 225Ac-PSMA-617 standard dose per cycle. In this group, 55 patients presented with a best PSA-response of ≥ 50 %, resulting in a best-PSA50% response rate of 52%. 129 patients received a combination treatment of 4 MBq 225Ac-PSMA-617 (Range 2-6 MBq) plus 4 GBq 177Lu-PSMA-617 (Range 2-6 GBq) per cycle. In this group, the best PSA decline of ≥ 50 % was observed in 74 patients with the best-PSA50% response rate of 57%. In patients who were lost for follow-up and no PSA was provided, progression was assumed.

RATHKE H;  WINTER Erik;  BRUCHERTSEIFER Frank;  HABERKORN Uwe;  MORGENSTERN Alfred;  KRATOCHWIL Clemens; 

2022-12-21

SOC NUCLEAR MEDICINE INC

JRC128883

0161-5505 (online),   

https://jnm.snmjournals.org/content/63/supplement_2/2202,    https://publications.jrc.ec.europa.eu/repository/handle/JRC128883,