Clinical trials

The purpose of this study is to evaluate the efficacy and safety of Letrozole SIE (injectable) compared to Femara® (oral tablet), both given together with ribociclib, for the first-line treatment of postmenopausal women with HR-positive, HER2-negative, inoperable locally advanced or metastatic breast cancer.

The study aims to compare the amount of the drug letrozole that gets into the bloodstream after multiple doses of the quarterly injection Letrozole SIE, versus multiple doses of the standard oral daily tablet of letrozole (Femara®), in women who have gone through menopause and have received treatment for hormone receptor-positive early breast cancer. Participants must have completed at least five years of hormone therapy with at least two of those years with letrozole before starting their participation in the study. Women who have completed four years of hormone therapy are also eligible if their doctor considers them at low risk of cancer returning.