Receptor tyrosine kinase co-amplification and benefit from HER2 inhibitors in biliary tract cancers

Targeting the human epidermal growth factor receptor 2 (HER2) has emerged as a promising therapeutic strategy for advanced biliary tract cancer (BTC). Javle et al. have recently reported a sub-analysis of the MyPathway trial on the efficacy of dual HER2 inhibition with pertuzumab plus trastuzumab in advanced BTC with ERBB2 amplification. After a median follow up of 8.1 months, 23% of patients achieved partial response, with a median duration of response of 10.8 months, median progression-free survival (PFS) of 4.0 months, and median overall survival of 10.9 months.