Experience and Prognostic Analysis with Avelumab Switch Maintenance Treatment in Metastatic Urothelial Carcinoma.

ABSTRACT

INTRODUCTION: Avelumab (Ave) is approved for metastatic urothelial carcinoma (mUC) maintenance therapy and prolongs overall survival (OS). We explored trends related to Ave treatment of mUC patients. METHODS: A total of 72 patients with mUC treated with first-line chemotherapy, from January 2019 to November 2022, at our affiliated institutions, were analyzed. We compared clinical parameters and the prognosis of patients treated with Ave (n = 43) because of progression during first-line chemotherapy, with untreated patients (Ave-untreated; n = 29). Among the Ave-treated group, we classified patients showing a complete or partial response or stable disease in their best response to Ave maintenance therapy as Ave-suitable patients; these were retrospectively analyzed. Potential prognostic factors, including the Geriatric Nutritional Risk Index (GNRI) for determining patients suitable for Ave, were evaluated. RESULTS: The basic clinical parameters of patients when first-line treatment was initiated were not statistically different between the two groups. The Ave-suitable group (median 26.6 months, 95% confidence interval [CI] 19.4-not reached [NR]) showed significantly longer median OS after first-line treatment than the Ave-untreated group (median 12.0 months, 95% CI 7.5-NR) with tolerable adverse events. The cut-off values of prognostic factors were set by the receiver operating characteristic curve. Low age and GNRI sustainability were revealed as significant prognostic factors for being Ave-suitable both in univariate and multivariate analysis. CONCLUSION: In mUC, Ave maintenance prolonged OS within tolerable safety profiles. GNRI sustainability may be used as a biomarker to predict being Ave-suitable.