seribantumab seribantumab seribantumab (inn; development code mm-121) is a monoclonal antibody designed for the treatment of cancer. seribantumabmonoclonal antibodytype?sourcehumantargether3clinical dataother namesmm-121atc codenoneidentifierscas number1334296-12-6iuphar/bps8297chemspidernoneunii1n3l70mdfxkeggd11777chemical and physical dataformulac6340h9810n1690o1986s52molar mass143151.18 g·mol−1 this drug was developed by sanofi/merrimack pharmaceuticals, inc.