Speaker
Dr
Benedikt Feuerecker
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Description
**Aim:** Despite the approval of several new agents metastatic castration resistant prostate cancer is still a major medical challenge. The beta-emitting Lu-177-PSMA radioligand therapy (RLT) is a new option but its antitumor effect can decrease over time. The aim of this retrospective analysis was to investigate safety and efficacy of the alpha emitting Ac-225-PSMA-617 RLT in mCRPC after Lu-177-PSMA failure.
**Methods:** 15 patients underwent Ac-225-PSMA-617 RLT between 10/17 and 08/18. All patients had previously received second line antihormonal treatment, as well as chemotherapy and had shown progression after Lu-177-PSMA therapy (median 2 cycles).Repeat PSMA-PET/CT before Ac-225-PSMA-617 therapy indicated continued high PSMA-expression. Patients were treated at 8 weekly intervals until progression or intolerable side effects. Prostate-specific antigen (PSA) and blood cell count were measured every 2-3 weeks. We report hematological and non-hematological side effects (Common Terminology Criteria for Adverse Events) and biochemical response.
**Results:** A total of 27 cycles of Ac-225-PSMA-617 (median dose 8 MBq, range 6–12.8) were applied. 5 patients received only 1 cycle, 8 patients 2 cycles and 2 patients 3 cycles. Baseline PSA was 758 ng/ml (range 49–4073). ECOG score was grade 0, 1 and 2 in 3, 10 and 2 patients, respectively. 10/15 patients showed any PSA-decline, 5/15 a PSA-decline of more than 50% and 3 patients no PSA-decline at any time. Grade 1-2 xerostomia occurred in 14 and 1 patient, respectively. 5/15 patients requested to stop treatment due to xerostomia. Two patients developed grade 2 renal insufficiency, 4 patients grade 3-4 anemia, 2 patients grade 3 thrombocytopenia. No grade 3-4 leucopenia was observed. 7/15 patients died during the observation period (median overall survival 8 months).
**Conclusion:** In this small cohort Ac-225-PSMA-617 RLT showed antitumor effect in mCRPC after Lu-177-PSMA failure. However, treatment had to be stopped in one third of the patients due to xerostomia.
| Email Address | benedikt.feuerecker@tum.de |
|---|---|
| Presentation Type | Contributed Oral |
Primary author
Dr
Benedikt Feuerecker
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Co-authors
Dr
Alfred Morgenstern
(European Commission, Joint Research Centre (JRC), Karlsruhe, Germany)
Mr
Ali Beheshti
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Dr
Calogero D'Alessandria
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Dr
Christof Seidl
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Dr
Frank Bruchertseifer
(European Commission, Joint Research Centre (JRC), Karlsruhe)
Dr
Karina Knorr
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Prof.
Margitta Retz
(Klinikum rechts der Isar, department of urology, Technical University of Munich, Munich, Germany)
Prof.
Matthias Eiber
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
Dr
Robert Tauber
(Klinikum rechts der Isar, department of urology, Technical University of Munich, Munich, Germany)
Prof.
Wolfgang Weber
(Klinikum rechts der Isar, department of nuclear medicine, Technical University of Munich, Munich, Germany)
