abemaciclib + olaparib + endocrine therapy

abemaciclib + olaparib + endocrine therapy is a therapeutic combination regimen used in the adjuvant treatment of high-risk, hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) early breast cancer. This specific combination is the focus of the ROYAL (Real wOrld studY in the Adjuvant Setting for High Risk earLy Breast Cancer Patients) study, an observational trial sponsored by the Azienda Ospedaliero-Universitaria di Modena. Abemaciclib is a selective inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6), which prevents the phosphorylation of the retinoblastoma protein, leading to cell cycle arrest in the G1 phase. Olaparib is a poly (ADP-ribose) polymerase (PARP) inhibitor that induces synthetic lethality in cells with deficiencies in homologous recombination repair, such as those with BRCA1/2 mutations. Endocrine therapy, which may include aromatase inhibitors or selective estrogen receptor modulators, works by reducing estrogen levels or blocking estrogen receptor signaling to inhibit the growth of hormone-sensitive tumor cells.