Under the priority review program, the FDA will decide on the BLA for avelumab within six months compared to 10-month review.
The company’s BLA submission follows data from a multicenter, single-arm, open-label, phase II study of 88 patients with metastatic MCC, whose disease had progressed after at least one chemotherapy treatment assessing the efficiency of avelumab.
The study showed a 31.8% objective response rate (ORR), in patients with MCC. Tumor responses were rapid, with 78.6% of patients responding within seven weeks of starting treatment, and durable, with 82.1% of patients still responding at the time of analysis.
The FDA earlier granted fast track and breakthrough therapy designations to avelumab for patients with metastatic MCC whose disease has progressed after at least one previous chemotherapy regimen.
Merck executive vice president, global head of research & development at the biopharma business Luciano Rossetti said: "We are pleased the FDA has granted a Priority Review designation for avelumab.
"There are currently no approved treatment options for metastatic MCC, and we are committed to working with the FDA to potentially bring the first approved cancer immunotherapy to patients with this aggressive disease."
Avelumab, a fully human anti-PD-L1 IgG1 monoclonal antibody, is being co-developed by Merck and Pfizer to treat a range of cancers under a strategic alliance formed in November 2014.
The antibody is believed to allow the activation of T-cells and the adaptive immune system by inhibiting PD-L1 interactions.
Image: The US FDA grants priority review to EMD Serono’s BLA for avelumab for Merkel cell carcinoma. Photo: courtesy of Merck KGaA, Darmstadt, Germany.