Breast Cancer Drug Combo Improved Progression-Free Survival in Phase 3 Study

MARCH 22, 2017
Jennifer Barrett, Assistant Editor

Eli Lilly and Company recently announced positive late-stage results in its clinical trial testing a combination of its experimental breast cancer drug and another widely-used treatment. The addition of abemaciclib to fulvestrant appeared to effectively improve progression-free survival in patients with breast cancer who had relapsed or did not receive adequate benefit from antiestrogen therapy.
The results are based on phase 3 of the key double-blind study, MONARCH 2, which evaluated the drug combination in women with hormone-receptor-positive HER2 negative advanced breast cancer. The study’s participants included patients who had relapsed or had progressed after endocrine therapy.
The study included 699 patients, who were then randomized to either receive abemaciclib or a placebo twice a day on a continuous dosing schedule in combination with fulvestrant at its approved dose and schedule, until disease progression. Patients who had received chemotherapy in a metastatic setting were not eligible to participate.
Abemaciclib, which is a cyclin-dependent kinase (CDK) 4 and CDK 6 inhibitor, demonstrated a significant improvement in progression-free survival rates when combined with fulvestrant, compared to patients who received fulvestrant a placebo. 
The most common adverse effects included diarrhea, neutropenia, nausea, and fatigue.
Officials with Lilly plan to submit the data to the FDA for regulatory review later this year.
Lilly announces phase 3 MONARCH 2 breast cancer study of abemaciclib met primary endpoint of progression-free survival [news release]. Lilly’s website. . Accessed Mar. 22, 2017.