Benefits of Verzenio After Surgery for Early-Stage Breast Cancer Confirmed
The monarchE study found that adding Verzenio (chemical name: abemaciclib) to hormonal therapy after surgery to remove early-stage, hormone receptor-positive, HER2-negative breast cancer with a high risk of recurrence (the cancer coming back) lowers that recurrence risk by about 25%. The 2020 results led to Verzenio’s approval by the U.S. Food and Drug and Administration (FDA) to treat early-stage disease in 2021.
Now, two more years of follow-up confirm those benefits.
The latest results were presented on Dec. 6, 2022, at the San Antonio Breast Cancer Symposium (SABCS) and published at the same time in The Lancet Oncology. Read the abstract of “Abemaciclib plus endocrine therapy for hormone receptor-positive, HER2-negative, node-positive, high-risk early breast cancer (monarchE): results from a preplanned interim analysis of a randomised, open-label, phase 3 trial.”
Doctors called treatments given after surgery adjuvant treatments.
About Verzenio
Verzenio is a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor. A kinase is a type of protein in the body that helps control cell division. Verzenio works by stopping cancer cells from dividing and growing.
Verzenio is a pill taken by mouth.
Characteristics that give cancer high recurrence risk
Early-stage, hormone receptor-positive, HER2-negative breast cancer with a high risk of recurrence has certain characteristics:
cancer cells present in four or more lymph nodes
cancer that is 5 centimeters or larger
cancer that is grade 3, which means the cancer cells look very different from normal cells and are growing quickly in disorganized, irregular patterns
cancer with high levels of Ki-67, a protein in cells that increases as they prepare to divide into new cells (high Ki-67 levels mean the cancer cells are dividing and forming new cells very quickly)
About the monarchE study
The monarchE study included 5,637 people diagnosed with early-stage, hormone receptor-positive, HER2-negative breast cancer with a high risk of recurrence — 5,601 women and 36 men. The people were from 38 countries around the world and joined the study between July 2017 and August 2019.
Most of the women in the study (56.5%) were post-menopausal when they were diagnosed. Nearly 60% of the people in the study were diagnosed with breast cancer that was in four or more lymph nodes.
Most of the people received other treatments for early-stage disease:
95.4% were treated with radiation therapy
95.4% were treated with chemotherapy
After breast cancer surgery, the people were randomly assigned to one of two treatment groups:
2,808 people took Verzenio for two years, plus hormonal therapy
2,829 took only hormonal therapy
People took one of two types of hormonal therapies:
68.3% of the people took an aromatase inhibitor
31.4% of the people took tamoxifen
The people are taking hormonal therapy for five to 10 years.
When the researchers presented early results in 2020, they’d followed the people for a maximum of only two years. At the time the data were analyzed, only 12.5% of the people in the study had completed the full two years of Verzenio treatment; 72.8% were still taking Verzenio.
Many doctors wondered if the benefits of Verzenio would last after people stopped taking the medicine. The latest results show that the benefits do last.
Updated results from monarchE
The latest findings come after about four years of follow-up, so all the people in the study have finished taking Verzenio.
Verzenio plus hormonal therapy reduced the risk of recurrence by 33.6% versus hormonal therapy alone:
336 people who took Verzenio and hormonal therapy had a recurrence
499 people who took only hormonal therapy had a recurrence
When the researchers looked at the graphs of how many people in the study were alive with no recurrence in each treatment group by month, they could see that the distance between the graphs gets larger as time goes on. This means that the benefits of Verzenio are increasing over time. The difference between recurrence rates in people taking Verzenio and hormonal therapy and people taking hormonal therapy alone were:
2.8% at two years of follow-up
4.8% at three years of follow-up
6.4% at four years of follow-up
Overall survival data — how long people lived whether or not the cancer recurred — weren’t ready for this analysis.
But the data do show that fewer people taking Verzenio and hormonal therapy died:
157 people taking Verzenio and hormonal therapy died
173 people taking hormonal therapy alone died
People taking Verzenio and hormonal therapy also were less likely to develop metastatic breast cancer:
125 people taking Verzenio and hormonal therapy were diagnosed with metastatic disease
249 people taking hormonal therapy alone were diagnosed with metastatic disease
Metastatic breast cancer is breast cancer that has spread to parts of the body away from the breast, such as the bones or liver.
“The clinically meaningful benefit of adjuvant abemaciclib added to endocrine therapy in hormone receptor-positive, HER2-negative, node-positive, high-risk early breast cancer persists beyond completion of abemaciclib therapy, yielding an increase in absolute [invasive disease-free survival] and [distant recurrence-free survival benefit at four years,” said Stephen Johnston, MA, PhD, FRCP, professor of breast cancer medicine and head of the Breast Unit at the Royal Marsden NHS Foundation Trust in London, who presented the research. “While [overall survival] remains immature at this time, the lower number of deaths in the abemaciclib arm compared to the endocrine therapy arm suggest that a survival signal favoring abemaciclib is emerging.
“These data further support the addition of adjuvant abemaciclib to endocrine therapy for patients with hormone receptor-positive, HER2-negative, node-positive, high-risk, early breast cancer.”
What this means for you
If you’ve been diagnosed with early-stage, hormone receptor-positive, HER2-negative breast cancer with a high risk of recurrence and are deciding on treatments after surgery, you may want to ask your doctor about these latest results and how they could apply to your unique situation.
If you’re already taking Verzenio and hormonal therapy, the results confirm that the benefits of Verzenio continue even if you’ve finished taking the medicine.
Learn more about Verzenio.
Editor’s Note: On March 3, 2023, the FDA changed the way doctors decide if an early-stage, hormone receptor-positive, HER2-negative, node-positive breast cancer has a high risk of recurrence to see if Verzenio can treat it. The change removed the Ki-67 score requirement. So now doctors use node status, cancer size, and cancer grade to decide if the cancer has a high risk of recurrence.
— Last updated on May 25, 2023 at 2:46 PM