Long-term Safety of Avelumab First-line Maintenance for Advanced UC

Post hoc analyses from JAVELN Bladder 100 that will be presented at the American Society of Clinical Oncology 2023 Annual Meeting shed light on the long-term safety profile of avelumab first-line maintenance for patients with advanced urothelial carcinoma (UC).

The phase 3 trial enrolled patients with advanced UC who had not progressed after first-line platinum-based chemotherapy. Results showed significantly prolonged overall survival and progression-free survival with avelumab first-line maintenance plus best supportive care (BSC) compared with BSC alone.

Additionally, the safety profile of avelumab was consistent with prior avelumab monotherapy studies; no new safety signals were identified and no detrimental impact on quality of life was noted.

Joaquim Bellmunt, MD, PhD, and colleagues reported post hoc safety analyses in the avelumab-plus-BSC arm after a minimum of 2 years of follow-up. They noted that trial treatment continued until disease progression, unacceptable toxicity, or withdrawal of consent.

Median follow-up at data cutoff was 38 months. In the 344 patients who received at least 1 dose of avelumab, median treatment duration was 5.8 months and median number of infusions was 11.5.

Treatment-related adverse events (AEs) of any grade were reported in 269 patients, and 19.5% of patients experienced events grade 3 or higher. Forty patients had a treatment-related AE that led to treatment discontinuation.

Immune-related AEs of any grade occurred in 111 patients, and 7.6% of patients experienced events grade 3 or higher. Serious immune-related AEs occurred in 18 patients, of which immune-related nephritis or renal dysfunction was the most common. Twenty-one patients had an immune-related AE that led to treatment discontinuation.

Among the 118 patients treated with avelumab for at least 12 months, immune-related AEs occurred after 12 months in 27 patients, including grade 3 or higher events in 4.2% of patients. Immune-related rash was the most common immune-related AE of any grade after 12 months of treatment.

Researchers concluded that the acceptable long-term safety profile of avelumab first-line maintenance is confirmed. “These results further support the use of avelumab first-line maintenance until progression as standard of care for patients with advanced urothelial carcinoma without progression after first-line platinum-based chemotherapy,” they added.