Alpelisib – the first PI3K inhibitor in the treatment of hormone‑positive, HER2‑negative breast cancer

05/2021

MUDr. Stanislav Hloušek

Onkologická klinika 1. LF UK a VFN, Praha

SUMMARY

Despite all the progress of recent years, hormone therapy is still the main treatment modality in most patients with breast cancer. However, even for this treatment, resistance and disease progression may develop over time then it is necessary to find therapy for the second and higher lines of treatment. A suitable candidate for this situation appears to be alpelisib - an α-specific phosphatidylinositol-3-kinase (PI3K) inhibitor which, in combination with fulvestrant, has been shown to be effective in patients with advanced hormone-dependent, human epidermal growth factor receptor 2-negative (HER2-negative) breast cancer where PI3K catalytic subunit alpha (PIK3CA) mutations have been identified, after disease progression to hormonal therapy, even if cyclin dependent kinase 4/6 (CDK4/6) inhibitors have been used. This efficacy was documented in the SOLAR-1 study in patients after hormonal treatment failure compared to placebo and in the BYLieve study, which enrolled patients after previous progression to CDK4/6 inhibitors.

Key words

PI3KCA mutation, PI3K, resistance to hormone therapy, PI3K/Akt/mTOR pathway, CDK4/6 inhibitors