1814P - First real-life data on [177Lu]Lu-PSMA-617: Descriptive analysis on the largest metastatic castration-resistant prostate cancer (mCRPC) cohort treated in early access in France

Background

VISION study showed that [¹⁷⁷Lu]Lu-PSMA-617 added to BSoC prolonged imaging based progression-free survival and overall survival in patients (pts) with PSMA-positive mCRPC. French Health Authorities has granted a "cohort” early access for [¹⁷⁷Lu]Lu-PSMA-617 in this indication.

Methods

PSMA positive pts with mCRPC pretreated with 1-2 taxane chemotherapy and ≥1 androgen receptor pathway inhibitor (ARPI) were included. Treatment administration planned 6 IV of [¹⁷⁷Lu]Lu-PSMA-617 (7.4 GBQ) every 6 weeks. Pts’ characteristics, efficacy and safety data were collected during the 6 follow-up visits (average: 17,1 ± 11,2 weeks). AE grading was not evaluated.

Results

From 12/1/2021 to 1/31/2023, 664 pts were exposed to treatment. At data closure, 428 were still under treatment, and 236 stopped treatment due to disease progression (50.2%), adverse events (AE) (14.0%) or death (11.0%; 1 death suspected to be due to the treatment). 42 pts (17.6%) completed all 6 injections. Pts baseline characteristics: median age 72.9 years; ECOG status 0-1: 85.4%; median PSA level 81.94 ng/ml; metastases: bone 94.1%, lymph node 63.0%, liver 11.3%; prior taxane regimen: 97.4% of which 65.5% received 2 taxane; prior ARPI treatment: 100% of which 67.9% received 2-5 previous ARPI treatments. For pts who received all injections, disease control was estimated by radiological (2.7% CR, 40.5% PR, 27.0% SD), clinical (11.9% clinical improvement and 78.9% stabilization), and PSA evaluation (34.2% decreased PSA level and 34.2% stabilization). 11.9% of pts experienced >1 treatment-related AE, including 63 pts with ≥1 serious AE. 3 fatal cases and 3 life-threatening cases related to treatment have been reported. The most reported AEs were thrombocytopenia (5.7% of pts) and anemia (4.5% of pts).

Conclusions

We observed a higher incidence of prior 2 taxane regimen and lymph nodes metastases at baseline compared to VISION study but the safety profile of [¹⁷⁷Lu]Lu-PSMA-617 remains safe and well tolerated. Since the study is still ongoing, updated efficacy results will be further analyzed and presented at ESMO congress, including longer follow-up period and higher number of pts who completed treatment.

Clinical trial identification

Editorial acknowledgement

Fabien DUVAL, KPL Agency, provided assistance in the writing of this abstract.

Legal entity responsible for the study

AAA Novartis.

Funding

AAA Novartis.

Disclosure

A. Giraudet: Financial Interests, Institutional, Advisory Board: AAA Novartis, Curium, Amgen, Sanofi. V. Massard: Financial Interests, Institutional, Writing Engagement: AAA Novartis, Astellas, Bayer, Janssen, Pfizer. A. Flechon: Financial Interests, Institutional, Advisory Role: Novartis, AAA Novartis, Janssen, Bayer, Astellas, AstraZeneca, Pfizer, Merck. S. Girault: Financial Interests, Institutional, Advisory Role: AAA Novartis. P. Barthelemy: Financial Interests, Personal, Advisory Board: BMS, MSD, Merck, Pfizer, Ipsen, Bayer, Janssen Cilag, Astellas, Novartis, Amgen, Gilead; Financial Interests, Personal, Invited Speaker: AstraZeneca, Seagen. C. Bailly: Financial Interests, Institutional, Advisory Role: Novartis, Boston Scientific, Sirtex. C. Viala: Financial Interests, Institutional, Advisory Board: BMS, MSD, AAA Novartis. G. Roubaud: Financial Interests, Personal, Advisory Board: Janssen, Astellas, Bayer; Financial Interests, Institutional, Advisory Board: Pfizer, AstraZeneca; Financial Interests, Institutional, Invited Speaker: Novartis; Financial Interests, Institutional, Coordinating PI: Bayer. All other authors have declared no conflicts of interest.