Avelumab First-line Maintenance for Advanced Urothelial Carcinoma: Long-term Outcomes from the JAVELIN Bladder 100 Trial in Patients with Nonvisceral or Lymph Node–only Disease

In the JAVELIN Bladder 100 randomized phase 3 trial (N = 700), avelumab first-line maintenance plus best supportive care (BSC) significantly prolonged overall survival (OS; primary endpoint) and progression-free survival (PFS) versus BSC alone in patients with advanced urothelial carcinoma (aUC) without progression after first-line platinum-based chemotherapy (PBC). Here, we report exploratory analyses of subgroups with nonvisceral metastases at the start of PBC (including bone metastases) or lymph node–only disease at randomization. The median OS with avelumab versus control in patients with nonvisceral metastases (n = 318) was 31.4 versus 17.1 mo (hazard ratio [HR], 0.60 [95% confidence interval {CI}, 0.45–0.79]), and in patients with lymph node–only disease (n = 102), it was 31.9 versus 22.7 mo (HR, 0.86 [95% CI, 0.51–1.47]). In patients with nonvisceral metastases, prolonged OS was observed with avelumab irrespective of the response to PBC or PBC regimen received. PFS analyses favored avelumab over control in all the subgroups. Incidences of avelumab-related adverse events were similar across the subgroups. Limitations include small sample sizes and the exploratory nature of analyses. Overall, exploratory analyses suggest that in first-line PBC-treated patients without progression, avelumab maintenance is effective and has a manageable toxicity profile in patients with aUC who have nonvisceral metastases or lymph node–only disease.