This ADC product is comprised of an anti-CD19 monoclonal antibody (clone huB4) conjugated via a MC linker to MMAF. The MMAF is targeted to certain cancers by immunerecognition and delivered into cancer cells via receptor mediated endocytosis. Within the cell, MMAF binds to tubulins, interrupts microtubule dynamics, and subsequently, induces cell death. Noncleavable linkers, is considered noncleavable-meaning linker cleavage, and payload release does not depend on the differential properties between the plasma and some cytoplasmic compartments. Instead, the release of the cytotoxic drug is postulated to occur after internalization of the ADC via antigen-mediated endocytosis and delivery to lysosomal compartment, where the antibody is degraded to the level of amino acids through intracellular proteolytic degradation. Derived from Auristatin,are water-soluble dolastatin analogs of dolastatin 10. Dolastatin 10 belongs to dolastatin family and it can powerfully bind to tubulin, thus inhibiting polymerization mediated through the binding to the vinca alkaloid binding domain, and causes cell to accumulate in metaphase arrest.