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Ado-trastuzumab emtansine

Hepatotoxicity, Cardiac Toxicity, Embryo-Fetal Toxicity

Do Not Substitute KADCYLA for or with trastuzumab. (2.1)


  • Serious hepatotoxicity has been reported, including liver failure and death in patients treated with KADCYLA. Monitor serum transaminases and bilirubin prior to initiation of KADCYLA treatment and prior to each KADCYLA dose. Reduce dose or discontinue KADCYLA as appropriate in cases of increased serum transaminases or total bilirubin. (2.25.1)

Cardiac Toxicity

  • KADCYLA administration may lead to reductions in left ventricular ejection fraction (LVEF). Evaluate left ventricular function in all patients prior to and during treatment with KADCYLA. Withhold treatment for clinically significant decrease in left ventricular function. (2.25.2)

Embryo-Fetal Toxicity:

  • Exposure to KADCYLA during pregnancy can result in embryo-fetal harm. Advise patients of these risks and the need for effective contraception (

FDA and Industry Communications

Index to FDA Drug Safety Information 

Patient Counseling Information


Package Inserts

Ado-Trastuzumab emtansine

Updated December 2022