In a nutshell
This phase 3 clinical trial investigated the safety and efficacy of lapatinib (Tykerb) in women with HER2 positive early-stage breast cancer.
Some background
HER2-positive (HER2+) breast cancer is a type of cancer where a protein named human epidermal growth factor receptor 2 (HER2) is present on the surface of the breast cells. This protein promotes the growth of cancer cells. Treatments for this type of breast cancer include drugs that target the HER2 protein (targeted therapies), with or without chemotherapy. A standard targeted therapy drug for patients with HER2+ breast cancer is trastuzumab (Herceptin). However, not all patients can get access to this drug. Therefore, there is need for alternative targeted therapy drugs that have similar mechanism of action and easy availability. Another targeted therapy drug approved for the treatment of patients with HER2+ breast cancer is lapatinib.
Methods & findings
Overall, 3147 women with HER2+ breast cancer from multiple centers and 33 different countries participated in this trial. All patients had previously been treated with chemotherapy. 1571 patients were randomly assigned to receive lapatinib (1500 mg) and 1576 patients received placebo (a substance with no medical effects used as a control when testing new drugs) daily for 12 months. Patients were followed up for approximately 4 years and the main parameters evaluated were disease-free survival events (defined as the return of the cancer, development of a new cancer, side effects or death). In all, disease-free survival events occurred in 13% of patients in the lapatinib group compared to 17% of patients in the placebo group. Side effects such as diarrhea, skin rash or nausea were more common in patients treated with lapatinib.
The bottom line
In summary, this study found a small improvement in disease-free survival in patients with early-stage HER2+ breast cancer treated with lapatinib.
The fine print
A limitation of this study is that not all patients included had HER2+ breast cancer. Future studies need to include a more carefully selected population of patients. Also, this study does not compare lapatinib to the standard treatment with trastuzumab in HER2+ breast cancer patients.
Published By :
Lancet oncology
Date :
Dec 10, 2012
