Avelumab in European patients (pts) with metastatic Merkel cell carcinoma (mMCC): experience from an ad hoc expanded access program (EAP)
Avelumab—a human anti–PD-L1 IgG1 monoclonal antibody—showed favorable efficacy and safety in pts with mMCC in the phase 2 JAVELIN Merkel 200 trial (NCT02155647), leading to its approval in multiple countries. Here, we describe real-world experience with avelumab in European pts with mMCC.
European pts participating in the EAP (NCT03089658) had stage IV mMCC and progressive disease (PD) on/after chemotherapy or were ineligible for either chemotherapy or participation in clinical trials. In contrast to JAVELIN Merkel 200, pts could have ECOG PS ≥ 2, treated brain metastases, or immunosuppressive conditions. Pts received a 3-mo supply of avelumab (administered 10 mg/kg IV Q2W until PD or unacceptable toxicity); resupply was allowed for pts with complete response (CR), partial response (PR), stable disease, or clinical benefit per physician assessment. No central imaging was obtained.
As of April 30, 2018, of 521 requests for avelumab across 37 countries, 343 were received in Europe: 305 were approved (including 20 for immunocompromised [IC] pts), 29 were medically rejected, and 9 were withdrawn. Most requests were from France (n = 96) and Italy (n = 87). 275 European pts received avelumab. Median age was 73 y (range, 28-95 y), and 69% of pts were male. Of 250 pts on treatment >3 mo, 145 (58%) had either unevaluable tumors or no data reported (including 11 IC pts). Of 105 evaluable pts, physician-assessed objective responses were observed in 54.3% (57 pts; including 3 IC pts [2 CR and 1 PR]) with 25.7% CR (27 pts) and 28.6% PR (30 pts). Median duration of treatment in pts with response was 195 d (range, 30-570 d). The disease control rate in evaluable pts was 75%. No new safety signals were reported. The EAP is ongoing but closing in 2018 as required postapproval.
The avelumab EAP provides an alternative treatment option for pts with mMCC with PD on/after chemotherapy or who are ineligible for either chemotherapy or clinical trials. In a real-world setting, avelumab showed efficacy and safety consistent with JAVELIN Merkel 200.
Clinical trial identification
Trial Protocol Number: NCT03089658