Verzenio a New CDK4/CDK6 Inhibitor Approved for Metastatic Breast Cancer
On September 28, 2017, the FDA approved abemaciclib (Verzenio; Eli Lilly), a cyclin-dependent kinase (CDK)4/CDK6 inhibitor, in combination with fulvestrant, for the treatment of women with hormone receptor (HR)-positive, HER2-negative advanced or metastatic breast cancer that progressed after endocrine therapy, and as monotherapy for HR-positive, HER2-negative advanced or metastatic breast cancer that progressed after endocrine therapy and previous chemotherapy in the metastatic setting.
“Verzenio provides a new targeted treatment option for certain patients with breast cancer who are not responding to treatment, and unlike other drugs in the class, it can be given as a stand-alone treatment to patients who were previously treated with endocrine therapy and chemotherapy,” said Richard Pazdur, MD, Director, FDA’s Oncology Center of Excellence.
The FDA approval of abemaciclib in combination with fulvestrant was based on the MONARCH 2 clinical trial, which included 669 patients with HR-positive, HER2-negative breast cancer whose disease progressed after endocrine therapy and who had not received chemotherapy in the metastatic setting. The median progression-free survival was 16.4 months with abemaciclib plus fulvestrant versus 9.3 months with placebo plus fulvestrant (P <.0001).
The FDA approval of abemaciclib as monotherapy was based on data from 132 patients in the single-arm MONARCH 1 clinical trial. This study included patients who had HR-positive, HER2-negative breast cancer whose disease progressed during or after endocrine therapy, and who had received chemotherapy in the metastatic setting. The investigator-assessed objective response rate with abemaciclib monotherapy was 19.7%, and the median duration of response was 8.6 months.
The most common (≥20%) adverse reactions reported with abemaciclib therapy were diarrhea, neutropenia, nausea, abdominal pain, infections, fatigue, anemia, leukopenia, decreased appetite, vomiting, headache, and thrombocytopenia.