Abstract 5529
Background
The treatment of mCRPC is 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
At data analysis 03/19 18 patients (pts) underwent Ac-225-PSMA-617 RLT between 10/17 and 12/18. All pts had previously received second line antihormonal treatment and 17/18 pts taxane based chemotherapy. All pts had shown progression after Lu-177-PSMA therapy (median 2 cycles). High PSMA-expression of the tumor lesions in PSMA-PET/CT before Ac-225-PSMA-617 was mandatory. Pts 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 updated data of hematological and non-hematological side effects, biochemical response and a subgroupanalysis.
Results
A total of 36 cycles of Ac-225-PSMA-617 (median dose 8 MBq, range 4,4–12.8) were applied. 7 pts received only 1 cycle, 5 pts 2 cycles, 5 pts 3 cycles and 1 patient 4 cycles. Baseline PSA was 822 ng/ml (range 49–4073). ECOG score was grade 0, 1 and 2 in 3, 13 and 2 pts. 15/18 pts showed any PSA-decline, 5/18 a PSA-decline of more than 50% and 3 pts no PSA-decline at any time. 6 weeks after treatment 12/18 showed any PSA decline and 4/18 a PSA-decline of > 50%. Grade 1 xerostomia occurred in 17 and grade 2 in 1 patient. 6/18 pts (33%) requested to stop treatment due to xerostomia. 2 pts developed grade 2 renal insufficiency, 5 pts grade 3-4 anemia, 2 pts grade 3-4 thrombocytopenia and 2 pts 3-4 leucopenia. 7/18 pts died during the observation period (median overall survival 9,6 months). The PSA-progression free survival was 1,3 months. In a subgroupanalysis of 9 pts with a rapid progression under a previous Lu-177-PSMA treatment 7 pts achieved any PSA-decline and 4 pts a decline of more than 50%.
Conclusions
In this small cohort Ac-225-PSMA-617 RLT showed antitumor effect in mCRPC after Lu-177-PSMA failure even after rapid tumour progression. However, treatment had to be stopped in one third of the pts due to xerostomia.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5105 - Fresh blood Immune cell monitoring in patients treated with nivolumab in the GETUG-AFU26 NIVOREN study: association with toxicity and treatment outcome
Presenter: Aude DESNOYER
Session: Poster Display session 3
Resources:
Abstract
1877 - Advanced clear-cell renal cell carcinoma (accRCC): association of microRNAs (miRNAs) with molecular subtypes, mRNA targets and outcome.
Presenter: Annelies Verbiest
Session: Poster Display session 3
Resources:
Abstract
5543 - Prior tyrosine kinase inhibitors (TKI) and antibiotics (ATB) use are associated with distinct gut microbiota ‘guilds’ in renal cell carcinoma (RCC) patients
Presenter: Valerio Iebba
Session: Poster Display session 3
Resources:
Abstract
2689 - mTOR mutations are not associated with shorter PFS and OS in patients treated with mTOR inhibitors
Presenter: Cristina Suarez Rodriguez
Session: Poster Display session 3
Resources:
Abstract
3069 - Efficacy of immune checkpoint inhibitors (ICI) and genomic alterations by body mass index (BMI) in Advanced Renal Cell Carcinoma (RCC)
Presenter: Aly-Khan Lalani
Session: Poster Display session 3
Resources:
Abstract
5089 - Finding the Right Biomarker for Renal Cell Carcinoma (RCC): Nivolumab treatment induces the expression of specific peripheral lymphocyte microRNAs in patients with durable and complete response.
Presenter: Lorena Incorvaia
Session: Poster Display session 3
Resources:
Abstract
2594 - Algorithms derived from quantitative pathology can be a gatekeeper in patient selection for clinical trials in localised clear cell renal cell carcinoma (ccRCC)
Presenter: In Hwa Um
Session: Poster Display session 3
Resources:
Abstract
2566 - High baseline blood volume is an independent favorable prognostic factor for overall and progression-free survival in patients with metastatic renal cell carcinoma
Presenter: Aska Drljevic-nielsen
Session: Poster Display session 3
Resources:
Abstract
2675 - Impact of estimand selection on adjuvant treatment outcomes in renal cell carcinoma (RCC)
Presenter: Daniel George
Session: Poster Display session 3
Resources:
Abstract
1541 - TERT gene fusions characterize a subset of metastatic Leydig cell tumors
Presenter: Bozo Kruslin
Session: Poster Display session 3
Resources:
Abstract