Retrospectively Analyzing the Use of CDK4/6 Inhibitors to Treat Adult Female Patients with Metastatic Breast Cancer

2020 Year in Review - Breast Cancer —January 25, 2021

Categories:

Breast Cancer

The majority of patients with metastatic breast cancer receiving treatment with CDK4/6 inhibitors had progression-free survival, behaving similarly when used as first-line therapy or after adjuvant hormonal therapy.

Silvia Comis, MD, Senior Medical Director, Oncology-Therapeutic Science and Strategy Unit, IQVIA, Milan, Italy, and colleagues used US open health claims and prescription data to examine the pattern of behavior of CDK4/6 inhibitor combinations as first-line therapy or following adjuvant hormonal therapy in adult females with de novo metastatic breast cancer.

The researchers examined metastatic breast cancer between 2015 and 2019, in adult female patients aged >18 years. Based on their first treatment, women were classified into 3 groups (group 1, hormonal; group 2, CDK4/6 inhibitor combinations; and group 3, everolimus combination).

The percentage of patients who switched to next therapy was 3.2% (1200 patients) of the 37,351 patients receiving CDK4/6 inhibitors as first-line therapy or following adjuvant hormonal therapy for advanced or metastatic diseases. For the majority of patients, in 87% of cases, changing therapy occurred within a 2-year period, and those patients who continued with first-line therapy did so for an extended period of time.

Compared with the overall CDK4/6 inhibitor population in groups 1 and 2, no statistically significant difference was apparent in the treatment pattern. However, within the first year of treatment, 90% of patients in group 3 compared with the overall patient population receiving CDK4/6 inhibitors switched to chemotherapy (P = .02).

A detailed analysis found that the overwhelming majority (90%) of patients receiving CDK4/6 inhibitors remained on therapy for approximately 1 year, with a small percentage of patients (2%) extending treatment to between 2 and 4.5 years.

The researchers concluded that for the period analyzed, 95% of patients receiving CDK4/6 inhibitors had progression-free survival. Overall, when used as first-line therapy or following adjuvant hormonal therapy, patients receiving CDK4/6 inhibitors had comparable patterns of behavior.

Source: Comis S, Kandasamy T, Perrin AJ, et al. A retrospective analysis of CDK4/6 inhibitors among adult female patients with metastatic breast cancer. J Clin Oncol. 2020;38(15_suppl). Abstract e13028.

Related Articles
Breast Cancer Year in Review Introduction
2020 Year in Review - Breast Cancer
Retrospective Analysis Provides Insight into Treatment-Emergent Neutropenia Among Patients with Metastatic Breast Cancer Treated with Ribociclib or Palbociclib
2020 Year in Review - Breast Cancer
Real-world data showed that patients with metastatic breast cancer receiving palbociclib had a numerically higher rate of neutropenia than patients receiving ribociclib.
Concurrent Use of Medications with Potential Drug–Drug Interactions: Real-World Analysis of Patients Treated with CDK4/6 Inhibitors
2020 Year in Review - Breast Cancer
In this real-world retrospective study, more patients in the ribociclib cohort compared with palbociclib and abemaciclib maintained starting doses and fewer patients decreased to 50% of the starting dose.
Last modified: March 11, 2021

Subscribe to the Journal of Oncology Navigation & Survivorship®

To sign up for our print publication or e-newsletter, please enter your contact information below.

  • First Name *
    Last Name *
     
     
    Profession or Role
    Primary Specialty or Disease State
    Country
  • Please enter your mailing address.

    Address
     
    Address Line 2
    City
     
    State
    Zip Code