The U.S. Food and Drug Administration has approved the use of Kadcyla (ado-trastuzumab emtansine, or T-DM1) to treat patients with HER2-positive, late-stage (metastatic) breast cancer. The new drug is for patients previously treated with trastuzumab and taxanes.
“Kadcyla is trastuzumab connected to a drug called DM1 that interferes with cancer cell growth,” Richard Pazdur, MD, Director of the FDA's Office of Hematology and Oncology Products, said in a news release. “Kadcyla delivers the drug to the cancer site to shrink the tumor, slow disease progression, and prolong survival. It is the fourth approved drug that targets the HER2 protein.”
In addition to T-DM1, trastuzumab, lapatinib, and pertuzumab are approved to treat HER2-positive breast cancer. Kadcyla was reviewed under the FDA's priority review program.
The drug's safety and effectiveness were evaluated in a clinical study of 991 patients randomly assigned to receive Kadcyla or lapatinib plus capecitabine. The study was designed to measure progression-free and overall survival, the length of time patients lived before death. Patients received treatment until the cancer progressed or side effects became intolerable.
Patients treated with Kadcyla had a median progression-free survival of 9.6 months compared with 6.4 months for patients treated with lapatinib plus capecitabine. Median overall survival was 30.9 months for the Kadcyla group and 25.1 months for the lapatinib plus capecitabine group.
Kadcyla carries a Boxed Warning alerting patients and health care professionals that the drug can cause liver toxicity, heart toxicity, and death. The drug can also cause severe life-threatening birth defects, and pregnancy status should be verified prior to starting Kadcyla treatment. Common side effects include nausea, fatigue, pain in the muscles or joints, low levels of platelets in the blood, increased levels of liver enzymes, headache, and constipation.
Kadcyla is marketed by Genentech, a member of the Roche Group.