According to a new study presented at the European Society for Medical Oncology (ESMO) 2014 Congress in Madrid, Spain, trastuzumab, a human epidermal growth factor receptor 2 (HER2)-targeted therapy, in combination with standard chemotherapy for the treatment of patients with HER2-positive breast cancer leads to better outcomes compared with lapatinib, an oral tyrosine kinase inhibitor (TKI), plus chemotherapy.
For the phase 3 Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization (ALTTO) study, researchers identified 8,381 patients from 946 centers in 44 countries. Patients received either lapatinib, trastuzumab, or both, in combination with standard chemotherapy.
Researchers revealed in June that lapatinib plus trastuzumab in addition to standard chemotherapy did not improve disease-free survival or overall survival, and increased toxicity. Now, the researchers' analysis shows that 14% of patients treated with trastuzumab experienced at least one disease event during 4.5 years of follow-up, while 18% of patients treated with lapatanib experienced at least one disease event. Furthermore, they found that patients that switched from lapatinib to trastuzumab experienced a benefit.
The study results suggest that trastuzumab, in combination with standard chemotherapy, should remain the standard of care for patients with HER2-positive breast cancer.
Analysis of more than 8,000 women who participated in the world’s largest study of two treatments for HER2-positive breast cancer reinforces other findings from the clinical trial showing that trastuzumab (Herceptin) should remain the standard of care for this cancer, says a Mayo Clinic researcher.
This study, being presented at the European Society for Medical Oncology (ESMO) 2014 Congress in Madrid, reveals that when used as a single HER2-targeted therapy in addition to standard chemotherapy, trastuzumab offers a better outcome than does lapatinib (Tykerb), says Edith A. Perez, M.D., deputy director at large, Mayo Clinic Cancer Center and director of the Breast Cancer Translational Genomics Program at Mayo Clinic in Florida.