Overall survival benefit with lapatinib in combination with trastuzumab for patients with human epidermal growth factor receptor 2-positive metastatic breast cancer: Final results from the EGF104900 study
Journal of Clinical Oncology, 06/15/2012
Clinical Article
Blackwell KL et al. – These data demonstrated a significant 4.5-month median OS advantage with the lapatinib and trastuzumab combination and support dual HER2 blockade in patients with heavily pretreated HER2-positive MBC.
Methods- Patients with HER2-positive MBC whose disease progressed during prior trastuzumab-based therapies were randomly assigned to receive lapatinib monotherapy or lapatinib in combination with trastuzumab.
- OS and updated PFS data are presented using Kaplan-Meier curves and log-rank tests stratified for hormone receptor and visceral disease status.
- Subgroup analyses were conducted to identify characteristics of patients deriving the greatest clinical benefit.
- In this updated final analysis of all patients randomly assigned with strata (n = 291), lapatinib plus trastuzumab continued to show superiority to lapatinib monotherapy in PFS (hazard ratio [HR], 0.74; 95% CI, 0.58 to 0.94; P = .011) and offered significant OS benefit (HR, 0.74; 95% CI, 0.57 to 0.97; P = .026).
- Improvements in absolute OS rates were 10% at 6 months and 15% at 12 months in the combination arm compared with the monotherapy arm. Multiple baseline factors, including Eastern Cooperative Oncology Group performance status of 0, nonvisceral disease, < three metastatic sites, and less time from initial diagnosis until random assignment, were associated with improved OS.
- Incidence of adverse events was consistent with previously reported rates.



