Designed to deliver antimicrotubule agent DM1 to HER2-positive cells

NCI: An antibody-drug conjugate (ADC) consisting of the recombinant anti-epidermal growth factor receptor 2 (HER2) monoclonal antibody trastuzumab conjugated to the maytansinoid DM1 via a nonreducible thioether linkage (MCC) with potential antineoplastic activity. The trastuzumab moiety of this ADC binds to HER2 on tumor cell surface surfaces; upon internalization, the DM1 moiety is released and binds to tubulin, thereby disrupting microtubule assembly/disassembly dynamics and inhibiting cell division and the proliferation of cancer cells that overexpress HER2. Linkage of antibody and drug through a nonreducible linker has been reported to contribute to the improved efficacy and reduced toxicity of this ADC compared to similar ADCs constructed with reducible linkers. (NCI Thesaurus)

Immunotoxin that consists of humanized monoclonal anti-HER2 antibody TRASTUZUMAB covalently linked to anti-microtubule agent MAYTANSINOID DM1 for treatment of metastatic breast cancer in patients who previously received trastuzumab and a TAXANES, separately or in combination.