The Food and Drug Administration has approved abemaciclib (Verzenio) to be given in combination with fulvestrant, to treat patients who have hormone receptor (HR)–positive, human epidermal growth factor receptor 2 (HER2)–negative advanced or metastatic breast cancer that has progressed after taking endocrine therapy.
This is the third cyclin-dependent kinase 4/6 (CDK4/6) inhibitor approved for the treatment of advanced breast cancer. Palbociclib (Ibrance) was granted accelerated approval in February 2015, in combination with letrozole, for the treatment of HR-positive, HER2-negative advanced breast cancer as initial endocrine-based therapy in postmenopausal women. Ribociclib (Kisqali) was approved in March 2017, in combination with any aromatase inhibitor, also for the treatment of HR-positive, HER2-negative advanced breast cancer as initial endocrine-based therapy in postmenopausal women.
Approval of abemaciclib in combination with fulvestrant was based on a median progression-free survival of 16.4 months for patients taking abemaciclib with fulvestrant, compared with 9.3 months for patients taking a placebo with fulvestrant, in a randomized trial. All 669 patients in the trial had HR-positive, HER2-negative breast cancer that had progressed after treatment with endocrine therapy and had not received chemotherapy once the cancer had metastasized.
Approval of abemaciclib as a single agent was based on an overall response rate of 19.7% in a single-arm trial of 132 patients with HR-positive, HER2-negative breast cancer that had progressed after treatment with endocrine therapy and chemotherapy after the cancer metastasized.
Common side effects of abemaciclib include diarrhea, neutropenia, leukopenia, nausea, abdominal pain, infections, fatigue, anemia, decreased appetite, vomiting, and headache.
Serious side effects include diarrhea, neutropenia, elevated liver blood tests, and deep venous thrombosis/pulmonary embolism, the FDA said.
Approval was granted to Eli Lilly.