McMMAF (GMP) refers to the GMP grade reagents of McMMAF. McMMAF is a protective group-conjugated MMAF. MMAF is a potent tubulin polymerization inhibitor.It is a MMAF derivative having a Maleimidocaproyl linker (MC linker), which is ready to conjugate to antibody or other proteins or biopolymers. Mafodotin is a useful agent for make antibody drug conjugate (ADC) for targeted drug delivery.

MMAF induces potent antitumor effects when conjugated via protease cleavable linkers to a monoclonal antibody targeting internalizing, tumor-specific cell surface antigens. MMAF is a new auristatin derivative with a charged C-terminal phenylalanine that attenuates its cytotoxic activity compared to its uncharged counterpart, Monomethyl auristatin E (MMAE). It cannot be used as a drug itself because MMAF is highly toxic. The linker to the monoclonal antibody is stable in extracellular fluid but is cleaved by cathepsin once the conjugate has entered a tumor cell, thus activating the anti-mitotic mechanism.