Trastuzumab binds to the HER2 (or c-erbB2) proto-oncogene, an EGF receptor-like protein found on 20-30% of breast cancer cells. The binding leads to antibody mediated (complement mediated) killing of the HER2 positive cells.

Used in the treatment of HER2-positive breast cancer. HER2 protein overexpression is observed in 25%-30% of primary breast cancers.Trastuzumab has been shown, in both in vitro assays and in animals, to inhibit the proliferation of human tumorcells that overexpress HER2. It is a mediator of antibody dependent cellular cytotoxicity, in that the binding of the antibody to HER2 overexpressing cells leads to preferential cell death.

Most likely removed by opsonization via the reticuloendothelial system.

Administration of trastuzumab can result in ventricular dysfunction and congestive heart failure. Risk of cardiotocity is especially elevated in patients recieving concurrent anthracycline or cyclophosphamide therapy.

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7. IGMT Link