Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer associated with a high risk of metastasis.,In 2017, avelumab (anti-programmed death-ligand 1 (PD-L1)) became the first approved treatment for patients with metastatic MCC (mMCC), based on the occurrence of durable responses in a subset of patients.,Here, we report long-term efficacy and safety data and exploratory biomarker analyses in patients with mMCC treated with avelumab.,In a cohort of this single-arm, phase 2 trial (JAVELIN Merkel 200), patients with mMCC and disease progression after prior chemotherapy received avelumab 10 mg/kg intravenously every 2 weeks.,The primary endpoint was confirmed objective response rate (ORR) by independent review per Response Evaluation Criteria in Solid Tumors V.1.1.,Other assessments included duration of response, progression-free survival, overall survival (OS), safety and biomarker analyses.,As of 14 September 2018, 88 patients had been followed up for a median of 40.8 months (range 36.4-49.7 months).,The ORR was 33.0% (95% CI 23.3% to 43.8%), including a complete response in 11.4% (10 patients), and the median duration of response was 40.5 months (95% CI 18.0 months to not estimable).,As of 2 May 2019 (≥44 months of follow-up), the median OS was 12.6 months (95% CI 7.5 to 17.1 months) and the 42-month OS rate was 31% (95% CI 22% to 41%).,Of long-term survivors (OS >36 months) evaluable for PD-L1 expression status (n=22), 81.8% had PD-L1+ tumors.,In exploratory biomarker analyses, high tumor mutational burden (≥2 non-synonymous somatic variants per megabase) and high major histocompatibility complex class I expression (30% of tumors with highest expression) were associated with trends for improved ORR and OS.,In long-term safety assessments (≥36 months of follow-up), no new or unexpected adverse events were reported, and no treatment-related deaths occurred.,Avelumab showed continued durable responses and meaningful long-term survival outcomes in patients with mMCC, reinforcing avelumab as a standard-of-care treatment option for this disease.,NCT02155647
Supplemental Digital Content is available in the text.,The overall survival (OS) of patients with metastatic uveal melanoma is short, the evidence for effectiveness of treatments is limited, and no consensus on the choice of treatment exists.,We aimed to advance interpretation of OS as an outcome by pooling peer-reviewed data.,The design is a systematic review and meta-analysis.,We searched PubMed from 1 January 1980, to 29 March 2017, for articles reporting patient-level survival in Kaplan-Meier or numerical form.,We digitized survival graphs, pooled individual survival times, calculated median OS by treatment modality, and compared each modality by the log-rank test and Cox regression using conventional chemotherapy (CHT) as a reference.,Individual-level data were obtained from 78 articles with 2494 patients.,The median OS across all treatment modalities was 1.07 years (range: 0.59-2.50 years).,Pooled OS reported after isolated hepatic perfusion [median OS: 1.34 years; hazard ratio (HR): 0.92, 95% confidence interval (CI): 0.87-0.97, P = 0.0040], immunoembolization (median OS: 1.63; HR: 0.97, 95% CI: 0.95-1.00, P = 0.0080), and surgery (median OS: 1.43; HR: 0.94, 95% CI: 0.92-0.96, P < 0.0001) was longer, and after checkpoint inhibitor shorter (median OS: 0.59; HR: 1.13, 95% CI: 1.06-1.20, P < 0.0001) than after CHT (median OS: 0.91 years), but subject to identifiable confounding factors.,OS following other modalities did not differ from CHT.,Reported OS was unassociated with the decade of publication, but depended on the percentage of first-line treated patients.,Our results suggest no clinically significant difference in OS by treatment modality or decade.,Most of the difference in reported OS likely is attributable to surveillance, selection, and publication bias rather than treatment-related prolongation.,Our pooled data provide benchmarks for future trials.