The U.S. Food and Drug Administration approved Eli Lilly‘s Verzenio (abemaciclib) in combination with an aromatase inhibitor as an initial treatment for postmenopausal women with advanced breast cancer.
Verzenio is for breast cancer tumors that are hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2-).
This is the third approval Verzenio has received in a five-month period, significantly expanding the drug’s treatment scope.
The treatment is a dual inhibitor of the cyclin-dependent kinases (CDK) 4 and 6. CDKs regulate cell proliferation and growth, and CDK4/6 specifically are often highly elevated in breast cancer, fueling the uncontrolled proliferation of cancer cells.
The FDA’s decision was supported by the positive results from the Phase 3 MONARCH trial (NCT02246621), which evaluated whether Verzenio delayed the time until disease progression in postmenopausal women with HR+, HER2- advanced breast cancer and had not had previous systemic therapy.
The study enrolled 493 women who were randomized to receive either Verzenio plus an aromatase inhibitor – Arimidex (anastrozole) or Femara (letrozole) – or placebo plus an aromatase inhibitor.
Patients treated on a continuous schedule of Verzenio plus an aromatase inhibitor remained free of disease worsening for 28.2 months (2.3 years) compared to 14.8 months (1.2 years) in placebo controls.
Among those treated with Verzenio, 54% responded to the therapy, defined as a reduction in tumor size by at least 30%. Complete tumor clearance was observed in 3.4%.
In the placebo group, however, 40.2% of patients responded and all were partial responders.
The median duration of response was 27.4 months with Verzenio vs. 17.5 months with placebo.
In September 2017, Verzenio was the first CDK inhibitor approved as a single agent or in combination with other therapies for the treatment of metastatic breast cancer in women.
“This approval is an important milestone, as it shows that Verzenio plus an aromatase inhibitor substantially reduced tumor size and delayed disease progression in women with HR+, HER2- metastatic breast cancer,” Joyce O’Shaughnessy, MD, Celebrating Women Chair in Breast Cancer Research at Baylor University Medical Center, said in a press release.
“Notably, the MONARCH 3 trial included patients with certain concerning clinical characteristics, such as a pattern of disease that spread to the liver. This information will help inform treatment decisions for each patient, which can be complicated in advanced breast cancer,” said O’Shaughnessy, also chair of the Breast Cancer Research Program at Baylor, Texas Oncology and U.S. Oncology in Dallas.
“Verzenio has now been developed, studied and clinically proven in three key trials to be effective for women with HR+, HER2- metastatic breast cancer – helping to ensure we are providing support to those who need it most,” said Sue Mahony, PhD, senior vice president and president of Lilly Oncology.