Resistance mutations that reactivate the PI3K/AKT/mTOR pathway occur in the context of PI3Kα inhibition, e.g., loss of PTEN/AKT activation in breast cancer patients treated with alpelisib or inavolisib, as well as further mutations in PI3Kα itself at progression [16, 17]. This evidence concerns the gene PIK3CB and breast carcinoma.