Angela Casbard

Summary Background Capivasertib, an AKT inhibitor, added to fulvestrant, was previously reported to improve progression-free survival in women with aromatase inhibitor-resistant oestrogen receptor (ER)-positive, HER2-negative advanced breast cancer. The benefit appeared to be independent of the phosphoinositide 3-kinase (PI3K)/AKT/phosphatase and tensin homologue (PTEN) pathway alteration status of tumours, as ascertained using assays available at the time.

We thank Tim Johannes Adrianus Dekker for his comments on the molecular analysis done in the FAKTION trial, but disagree that it was “muddled”. The eligibility criteria for the FAKTION trial included patients with non-measurable and bone-only disease. Taking the biopsy success rates from the SAFIR01 study, 1 André F Bachelot T Commo F et al.

Summary Background Capivasertib (AZD5363) is a potent selective oral inhibitor of all three isoforms of the serine/threonine kinase AKT. The FAKTION trial investigated whether the addition of capivasertib to fulvestrant improved progression-free survival in patients with aromatase inhibitor-resistant advanced breast cancer.