The difference between Ado-trastuzumab emtansine and trastuzumab

Ado-trastuzumab emtansine and trastuzumab (trastuzumab) are two drugs used to treat HER2-positive breast cancer, and there are some differences between them. Trastuzumab is a variant of trastuzumab that has stronger drug activity and directly kills cancer cells by releasing cytotoxins.

Emtansine is a conjugate of trastuzumab and emtansine (DM1), a microtubule inhibitor derived from maytansine. It enters HER2-expressing cancer cells together with trastuzumab and is degraded in lysosomes, leading to the release of DM1. DM1 binds to tubulin and disrupts the microtubule network, leading to cell cycle arrest and cell death. This conjugate has shown enhanced efficacy in advanced metastatic cancer when used in combination with other anti-tumor drugs. In 2013, trastuzumab was approved in the United States for previously treated advanced cancer. Antibody conjugates are supplied in Kadcyla brand disposable vials. The recommended dose is 3.6 mg/kg intravenously every 3 weeks until disease progression or intolerance. Antibody conjugates were associated with a higher incidence of adverse side effects than trastuzumab alone; more common adverse events included fatigue, nausea, myalgia, headache, constipation, elevated serum enzymes, and thrombocytopenia.

Trastuzumab is a humanized monoclonal antibody against HER2, a human growth factor receptor that is overexpressed in 20%-25% of breast cancers. The interaction of epidermal growth factor (EGF) with HER2 leads to rapid cell growth and proliferation through intracellular pathways including MAP and PI3 kinase. Trastuzumab's binding to the HER2 receptor blocks this cell signaling pathway and causes growth arrest. In women with HER2-positive cancer, trastuzumab reduces recurrence and extends survival. Trastuzumab was approved for use in the United States in 1998, and its current indications include HER2-expressing breast cancer and gastric cancer. Trastuzumab is available in multi-purpose vials under the generic brand name Herceptin. Typical dosage is 2-8 mg/kg intravenously per week, with the dose and duration of treatment varying depending on the indication. Common side effects include fatigue, nausea and vomiting, diarrhea, infusion reactions, rash, headache, neutropenia, infection, and anemia.

EnmetratrastuzumabThe monoclonal antigenic drug has been launched in China and has entered the scope of medical insurance. Only eligible patients can be reimbursed. SpecificationsThe price of 100mg per box may be around 20,000 yuan. This drug is a strictly controlled drug. Listed overseasEnmei trastuzumabThe single-cell generic drug has Turkish and European versions, specificationsThe price of each box of 100 mg may be around RMB 3,000-8,000 (the price may fluctuate due to exchange rates). The ingredients of the original drugs sold at home and abroad are basically the same. Currently, there are no generic drugs of Enmetra trastuzumab produced and launched.