ERBB2 and breast cancer: Results from a second overall survival interim analysis (data cut-off, 2 January 2017) of MONALEESA-2 showed that the PFS benefit was maintained for ribociclib at 25.3 months vs 16.0 months for the placebo group (HR = 0.568; 95% CI 0.457–0.704; P = 9.63 × 10−8), with a consistent PFS benefit across patient subgroups (Hortobagyi GN et al. Updated results from MONALEESA-2, a Phase III trial of first-line ribociclib + letrozole in hormone receptor-positive, HER2-negative advanced breast cancer.