At the beginning of March, the Food and Drug Administration (FDA) approved treatment of Abemaciclib (Verzenio) for two years, combined with hormonal therapy, for early stage breast cancer patients with hormone receptor-positive HER2-negative tumors who underwent surgery and are at high risk of recurrence (i.e. either ≥4 axillary lymph node involvement, or 1-3 axillary lymph node involvement and tumor grade 3, or a tumor size≥ 5 cm).

Abemaciclib is a type of targeted therapy. It is called "a cancer growth inhibitor", since by its unique mechanism it interferes with the growth of cancer cells which are eventually destroyed.

The approval was based on results from a clinical trial in which 5,120 breast cancer patients who met the abovementioned criteria were enrolled.

Patients were randomly assigned to receive either Abemaciclib for 2 years plus standard endocrine therapy (study group), or endocrine therapy alone (control group).

At about 4 years follow-up, the probability of disease recurrence was at least 30% lower for the study group patients receiving Abemaciclib combined with endocrine therapy, compared to those in the control group receiving endocrine therapy alone.

The treatment benefit continued after the 2-year treatment period of Abemaciclib and endocrine therapy.

Among the most common side effects were leukopenia, infections, nausea and headache.

Based on the promising study results, the researchers believe that the addition of Abemaciclib to adjuvant endocrine therapy can improve outcomes in patients with high-risk early stage breast cancer.