FDA Approves Kadcyla (Ado-Trastuzumab Emtansine) for Metastatic Breast Cancer
Drug will be available within 2 weeks (Feb. 22)
The FDA has approved Kadcyla (ado-trastuzumab emtansine, Genentech) for the treatment of patients with HER2-positive metastatic breast cancer who have received prior treatment with trastuzumab (Herceptin, Genentech) and a taxane chemotherapy.
An antibody–drug conjugate (ADC) is a new kind of targeted cancer medicine that can attach to certain types of cancer cells and deliver chemotherapy directly to them. Kadcyla is the first FDA-approved ADC for treating HER2-positive metastatic breast cancer, an aggressive form of the disease.
The FDA approval of Kadcyla is based on results from the EMILIA trial — a phase III, randomized, open-label study that compared Kadcyla alone with lapatinib (Tykerb, GlaxoSmithKline) in combination with capecitabine (Xeloda, Genentech) in 991 patients with HER2-positive locally advanced or metastatic breast cancer who had been treated with trastuzumab and a taxane chemotherapy.
The study met both co-primary efficacy endpoints of overall survival (OS) and progression-free survival (PFS). Patients who received Kadcyla lived a median of 5.8 months longer (OS) than did those who received the combination of lapatinib and capecitabine, the standard of care in this setting (median overall survival: 30.9 months vs. 25.1 months, respectively).
In addition, patients treated with Kadcyla experienced a 32% reduction in the risk of dying compared with those treated with lapatinib and capecitabine (hazard ratio [HR] = 0.68; P = 0.0006), and Kadcyla-treated patients lived significantly longer without their disease getting worse (PFS) compared with those who received lapatinib plus capecitabine (HR = 0.65; 35% reduction in the risk of disease worsening or death [P < 0.0001]; median PFS: 9.6 months vs. 6.4 months, respectively).
For patients receiving Kadcyla, the most common grade-3 or higher adverse events were low platelet counts (14.5%); increased levels of enzymes released by the liver and other organs (8.0%); low red blood cell counts (4.1%); low levels of potassium in the blood (2.7%); nerve problems (2.2%); and tiredness (2.5%).
Kadcyla consists of the antibody trastuzumab and the chemotherapeutic agent DM1, joined together using a stable linker. Kadcyla binds to HER2-positive cells and is thought to block out-of-control signals that make the cancer grow while also calling on the body’s immune system to attack the cancer cells. Once Kadcyla is taken up by those cells, it is designed to destroy them by releasing the DM1 inside the cells.
The drug will be available in the U.S. within 2 weeks.
Source: Genentech; February 22, 2013.