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

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.

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.

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.

In mUC, Ave maintenance prolonged OS within tolerable safety profiles. GNRI sustainability may be used as a biomarker to predict being Ave-suitable.