Effective treatment based on monitoring bESR1 mutations

Bidard and colleagues 1 Bidard FC Hardy-Bessard AC Dalenc F et al. Switch to fulvestrant and palbociclib versus no switch in advanced breast cancer with rising ESR1 mutation during aromatase inhibitor and palbociclib therapy (PADA-1): a randomised, open-label, multicentre, phase 3 trial. Lancet Oncol. 2022; 23: 1367-1377 Summary Full Text Full Text PDF PubMed Scopus (34) Google Scholar reported that the switching of aromatase inhibitor to fulvestrant according to rising ESR1 mutation in the blood (bESR1mut) during first-line aromatase inhibitor and palbociclib treatment improved progression-free survival in patients with advanced oestrogen receptor-positive, HER2-negative breast cancer. However, we have several concerns regarding the interpretation of the results of this study. Switch to fulvestrant and palbociclib versus no switch in advanced breast cancer with rising ESR1 mutation during aromatase inhibitor and palbociclib therapy (PADA-1): a randomised, open-label, multicentre, phase 3 trialPADA-1 is the first prospective randomised trial showing that the early therapeutic targeting of bESR1mut results in significant clinical benefit. Additionally, the original design explored in PADA-1 might help with tackling acquired resistance with new drugs in future trials. Full-Text PDF Effective treatment based on monitoring bESR1 mutations – Authors' replyWe thank Hoshie Hirai and colleagues for their interest in the PADA-1 study.1 Full-Text PDF