A retrospective, multicenter study of the efficacy of lapatinib plus trastuzumab in HER2 positive metastatic breast cancer patients previously treated with trastuzumab, lapatinib, or both: the TRASTYVERE study.
Targeting the human epidermal growth factor receptor 2 (HER2)-mediated signaling cascade with monoclonal antibodies or tyrosine kinase inhibitors was shown to be synergistic with cytotoxic agents and modified the natural history of HER2-positive breast cancer.
In the metastatic breast cancer scenario, maintenance of an anti-HER2 blockade over several lines of treatment has been proven to be clinically meaningful. In the first- and second-line, pertuzumab and trastuzumab-emtansine (T-DM1) were shown to be the more active options.
Multiple options are recommended after pertuzumab and T-DM1, including combinations with trastuzumab and lapatinib. On the other hand, the clinical activity of lapatinib after lapatinib and/or trastuzumab is currently unknown.
We designed this observational and retrospective study to evaluate the effectiveness in a real-world scenario of the lapatinib–trastuzumab combination in patients with HER2-positive metastatic breast cancer previously treated with lapatinib and/or trastuzumab.
Our study, which included 115 patients from 14 Spanish institutions, supports the hypothesis that combining the trastuzumab–lapatinib anti-HER2 agents is a safe and active chemotherapy-free option, even for patients who have previously failed to respond to prior lapatinib- and trastuzumab-based regimens.
It was a journey with many challenges, but the perseverance and effort of the site investigators and collaborators –as well as the MedSIR Operations team– were key in delivering these results. On behalf of MedSIR, we would like to thank all the patients who have participated in the TRASTYVERE trial as well as their families and support groups.
This retrospective, longitudinal, multicenter and observational study was designed and sponsored by MedSIR and funded by GlaxoSmithKline plc (GSK).
The publication in the Clinical Translational Oncology journal was accepted.
Author: Andrea Malfettone