328PRibociclib (RIBO) + letrozole (LET) in premenopausal patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC) with no prior endocrine therapy (ET) for ABC: Preliminary subgroup results from the phase IIIb CompLEEment-1 trial. (23rd October 2018) - Abdel-Razeq, H; Cottu, P H; Ring, A; De Laurentiis, M; Lu, J; Azim, H A; Zamagni, C; Zhou, K; Wu, J; Menon, L; Martín, M