Real-world clinical outcomes in avelumab-treated patients (pts) in the United States (U.S.) from SPEAR-Merkel: Study informing treatment pathway decisions in Merkel cell carcinoma (MCC).

Abstract

269 Background: MCC is a rare, aggressive disease associated with poor prognosis. Avelumab, a fully human anti–PD-L1 monoclonal antibody, was the first immune checkpoint inhibitor approved by the FDA for the treatment of metastatic MCC (mMCC). In the JAVELIN Merkel 200 trial (Clinical trial information: NCT02155647), avelumab resulted in durable responses and a high objective response rate (ORR) in pts with mMCC. This retrospective descriptive study assessed real-world clinical outcomes in avelumab-treated pts with locally advanced MCC (laMCC) and mMCC in a US community oncology setting. Methods: This study included data on avelumab-treated laMCC and mMCC pts from 1/1/17 to 3/31/19 within The US Oncology Network. Study data were captured through 9/30/19 using structured fields and chart review of iKnowMed electronic healthcare records. Real-world ORR was assessed. Duration of response (DOR), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Results: 33 pts initiated treatment with avelumab (laMCC n = 11; mMCC n = 22) and were followed up for a median of 10.9 months (range, 0.5-27.2 months). Median age was 77 years (range, 44-90+ years), 78.8% of pts were male, and the majority (84.8%) of pts were treated in the first-line setting. During treatment, 27.2% of pts had emergency department visits and 39.4% were hospitalized; 1% and 23.1%, respectively, were treatment related. Clinical outcomes are reported in the table. Conclusions: This is the first study to examine pts with laMCC treated with avelumab in a real-world setting. Although the sample population is small, results suggest the clinical benefits in the real world in pts with mMCC treated with avelumab are consistent with benefits reported in the JAVELIN Merkel 200 trial. [Table: see text]