At the recent American Society of Clinical Oncology annual conference, positive clinical trial results with lapatinib in various cancer types were presented. Lapatinib is a dual kinase inhibitor that targets the epidermal-growth-factor receptors 1 (EGFR or ERBB1) and 2 (HER2 or ERBB2).
A phase III open-label study reported by Charles Geyer was designed to evaluate time to progression (TTP) in women with ERBB2-positive trastuzumab-resistant advanced breast cancer treated with lapatinib plus capecitabine, or capecitabine alone. Of 321 women evaluated, the median TTP in the combination group was 36.9 weeks, compared with 19.7 weeks in the monotherapy group. Median progression-free survival was 36.9 weeks on combination therapy versus 17.9 weeks on capecitabine alone. Survival data are not yet mature, but are similar so far. The superior efficacy of the combination therapy has led the Independent Data Monitoring Committee to recommend discontinuing enrolment into the trial.
