Abemaciclib (Verzenio) in combination with an aromatase inhibitor has been approved as initial endocrine-based therapy for postmenopausal women with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer, the US Food and Drug Administration announced in a press release.
Approval was based on the results of the MONARCH 3 study, a randomized, double-blind, placebo-controlled, multicenter clinical trial in postmenopausal women with HR-positive, HER2-negative advanced or metastatic breast cancer. A total of 493 patients were randomized to receive either abemaciclib 150 mg or placebo orally twice daily, plus the treating physician’s choice of letrozole or anastrozole. The estimated median progression-free survival (PFS) (RECIST 1.1) was 28.2 months (95% CI: 23.5, not reached) for patients receiving abemaciclib and 14.8 months (95% CI: 11.2, 19.2) for those receiving placebo (HR 0.540; 95% CI: 0.418, 0.698; p<0.0001).
The most common adverse reactions that were seen in at least 20% of patients receiving abemaciclib in MONARCH 3 and were reported at a rate more than 2% higher than the rates seen in the placebo arm were diarrhea, neutropenia, fatigue, infections, nausea, abdominal pain, anemia, vomiting, alopecia, decreased appetite, and leukopenia.
The recommended starting dose of abemaciclib in combination with an aromatase inhibitor is 150 mg twice daily orally with or without food.
Abemaciclib (Verzenio) is manufactured by Eli Lilly.
Full prescribing information is available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/208855s000lbl.pdf.