Kadcyla May Be Better than Lapatinib for Advanced, HER2-Positive Breast Cancer That Has Spread to the Central Nervous System

The gist: People whose HER2-positive breast cancer has spread to their central nervous system (CNS) might survive longer if they are treated with the drug Kadcyla than if they take capecitabine plus lapatinib. That was the conclusion of a recent clinical trial with volunteer patients. Our Chief  Scientist speculates that the mild side effects of Kadcyla compared to those of the capecitabine/lapatinib combo might also make it a better choice.

“Patients with HER-2–positive advanced breast cancer treated with ado-trastuzumab emtansine experienced similar rates of central nervous system progression as those treated with capecitabine plus lapatinib, according to study results.

“However, among patients with treated, asymptomatic central nervous system (CNS) metastases at baseline, those assigned the antibody–drug conjugate ado-trastuzumab emtansine (Kadcyla, Genentech) experienced significantly longer OS than those assigned capecitabine plus lapatinib (Tykerb, GlaxoSmithKline).

“Ian E. Krop, MD, of the department of medical oncology at Dana-Farber Cancer Institute and Harvard University School of Medicine, and colleagues conducted a retrospective, exploratory analysis of data from the phase 3 EMILIA study.

“The EMILIA study included 991 patients with HER-2–positive advanced breast cancer who underwent previous treatment with trastuzumab (Herceptin, Genentech) and a taxane. Researchers randomly assigned 495 patients to ado-trastuzumab emtansine, and the other 496 received capecitabine plus lapatinib. Treatment continued until disease progression.”