LAUSR

The PIKTAM study evaluated the efficacy and safety of the PI3K inhibitor buparlisib in combination with tamoxifen in hormone receptor‐positive (HR+), HER2‐negative advanced breast cancer patients after failure of prior endocrine therapy. In this open‐label, single‐arm phase II trial, 25 patients were enrolled in 11 sites in Germany. Patients were stratified according to PIK3CA mutation status (tissue and cfDNA from serum samples) and/or loss of PTEN expression. Patients received buparlisib (100 mg) and tamoxifen (20 mg) once daily on a continuous schedule (28‐day cycle) until progression or unacceptable toxicity.