Blood eosinophils as prognostic biomarkers for advanced urothelial carcinoma in patients treated with avelumab: First results of the MALVA study (Meet-URO 25).

• DOI: 10.1200/jco.2023.41.16_suppl.e16570
• Publication Date: 2023-06-04T15:48:13Z
• Authors: Elisabetta Gambale; Marco Maruzzo; Carlo Messina; Irene De Gennaro ...; Ismaela Anna Vasc...; Virginia Rossi; Davide Bimbatti; Nicolò Cavasin; Marco Messina; Alessia Mennitto; Sara Elena Rebuzzi; Chiara Mercinelli; Martina Fanelli; Mariella Sorarù; Federico Scolari; Marinella Micol Mela; Laura Doni; Serena Pillozzi; Lorenzo Antonuzzo
• Keywords: Avelumab; Metastatic Urothelial Carcinoma; Maintenance therapy; Progression-free survival

e16570 Background: Platinum-based chemotherapies (CTs) represent the standard first-line treatment of advanced urothelial carcinoma (aUC). However, development resistance and toxicities to these regimens is responsible for poor progression-free survival (PFS) overall (OS). Maintenance with programmed death-ligand 1 (PD-L1) inhibitor avelumab after initial response CT improved significantly OS. Despite advantage, only a limited percentage patients (pts) benefits from immunotherapy. Therefore, prognostic/predictive factors immunotherapy are needed. Studies carried out on small cohorts pts melanoma, renal cell cancer or lung proved that eosinophil count variations could be used as prognostic during Thus, aim present study evaluate levels potential biomarker outcome among aUC enrolled in MALVA (Maintenance AVeLumAb neoplasms CT: an observational retrospective prospective study) ongoing (Meet-URO 25). Methods: The real-life multicentric retro-/prospective receiving maintenance platinum-based CT. co-primary endpoints OS PFS. We here data first 100 who received therapy between January 2021 2023. Absolute Eosinophil Counts (AEC) were registered at baseline (week 0) time tumor assessment 12). This aims whether AEC predictive efficacy treated avelumab. Results: One-hundred (median age, 72 years), 71.4% whom men, (data cut off, 2, 2023). Median follow-up was 8.5 months. duration 5.9 PFS entire population 8.7 months (95% CI; 5.7 months-not reached). Predefined subgroup analyses showed improvement (5.1 vs NR, p = 0.0031; 12.9 0.056 respectively) high week 0 low pts. Additionally, pilot analysis conducted 34 pts, stratified by longer (6.4 0.045) Conclusions: In order optimize aUC, reliable biomarkers required. this study, we provide homogeneous cohort investigating relevance eosinophils avelumab, suggesting easily accessible reproducible warrants further studies.