D’Angelo SP, et al. - Researchers investigated the efficacy of first-line avelumab treatment in patients with distant metastatic Merkel cell carcinoma (mMCC) via performing a preplanned interim analysis of a phase 2 study involving 39 patients with mMCC. They administered 10-mg/kg avelumab to patients by 1-hour intravenous infusion every 2 weeks until confirmed disease progression, unacceptable toxic effects, or withdrawal occurred. They observed high response rates to first-line avelumab therapy in patients with mMCC, which support previously reported antitumor activity following second-line or later treatment and progression-free survival, suggesting durability of the responses. Findings thereby provide support to avelumab’s approval in the United States and European Union as well as its use as a standard-of-care treatment for mMCC.