Additional Relevant Details
The Breakthrough Therapy designation is based primarily on positive results of the Phase III MONALEESA-2 trial of LEE011 in combination with letrozole in postmenopausal women who had received no prior therapy for their advanced disease[1]. The MONALEESA-2 trial met the primary endpoint of clinically meaningful improvement in progression free survival (PFS) at a pre-planned interim analysis. Results of this study will be presented at an upcoming medical congress and will form the basis of regulatory discussions in the US, Europe and other countries for use in this indication.

LEE011 (ribociclib) is a selective cyclin dependent kinase inhibitor, a new class of drugs that help slow the progression of cancer by inhibiting two proteins called cyclin dependent kinase 4 and 6 (CDK4/6). These proteins, when over-activated in a cell, can enable cancer cells to grow and divide too quickly.LEE011 has been studied in non-clinical models and is currently being evaluated in combination with additional endocrine agents as part of the MONALEESA (Mammary ONcology Assessment of LEE011'sEfficacy and SAfety) clinical trial program. LEE011 is not approved for any indication in any market at this time.MONALEESA-2 is a Phase III randomized, double blind, placebo controlled, multicenter global registration trial to evaluate the safety and efficacy of LEE011 in combination with letrozole compared to letrozole alone in postmenopausal women with HR+/HER2- advanced breast cancer who received no prior therapy for their advanced breast cancer[1]. MONALEESA-2 met the primary endpoint of clinically meaningful improvement in PFS at the pre-planned interim analysis and is continuing to assess overall survival data[1].MONALEESA-3 is a trial evaluating LEE011 in combination with fulvestrant compared to fulvestrant alone in men and post-menopausal women with HR+/HER2- advanced breast cancer who have received no or a maximum of one prior endocrine therapy. MONALEESA-3 is fully enrolled.MONALEESA-7 is a trial investigating LEE011 in combination with endocrine therapy and goserelin compared to endocrine therapy and goserelin alone in pre-menopausal women with HR+/HER2- advanced breast cancer who have not previously received endocrine therapy. MONALEESA-7 is fully enrolled and is the only Phase III study that focuses solely on pre and perimenopausal women with advanced breast cancer.