Real-world Data in Patients With Breast Cancer Treated With Abemaciclib (ENDURANCE)

Real-world Clinical Outcome and Toxicity Data in Patients With Breast Cancer Treated With Abemaciclib Combined With Endocrine Therapy: the Experience of the Hellenic Cooperative Oncology Group

The present study will assess real-world clinical outcomes and adverse events from treatment with endocrine therapy combined with abemaciclib in patients with HR-positive, HER2-negative advanced breast cancer.

Study Overview

• Status: Recruiting
• Conditions: Breast Cancer

Detailed Description

Protocol was amended in November 2021, after the recent FDA approval of abemaciclib in the adjuvant setting. On October 12, 2021, FDA approved abemaciclib with endocrine therapy for the adjuvant treatment of adult patients with hormone receptor -positive, HER2-negative, node-positive, early breast cancer at high risk of recurrence and a Ki-67 score ≥20%. Our study will now include real-world data on efficacy and toxicity of abemaciclib in the adjuvant setting as well. 2-negative advanced breast cancer. Patients who are enrolled and the patients to be enrolled will refer to a dedicated online platform (CARE ACROSS platform) where they can register their side-effects of cancer and the treatment received at frequent intervals. Patients will be randomized in the platform in two arms with an allocation 1:1(automatically by the platform). After every report of their side-effects, patients in Arm A will receive an acknowledgement and suggestion to stay in contact with their clinician. After every report of their side- effects, patients in Arm B will receive an acknowledgment and suggestion to stay in contact with their clinician; additionally they will receive personalised support (as a few word text) for each side-effect reported. Clinicians involved in the trial will refer patients (upon enrollment or to those already enrolled) to a dedicated online platform. Patients will sign up by entering their patient ID and their email address (and picking their password for security).

• Study Type: Observational
• Enrollment (Estimated): 108

Contacts and Locations

• Study Contact: Name: Elena Fountzilas, MD, PhD; Phone Number: +306945779709; Email: FOUNTZILA@ONCOGENOME.GR
• Study Contact Backup: Name: Areti Stamboliou; Phone Number: 23 +302106912520; Email: a_stampoliou@hecog.ondsl.gr

Study Locations

• Greece
  • Athens, Greece
    • Recruiting
    • Hellenic Oncology Cooperative Group
    • Contact: Elena Fountzilas, MD; Email: fountzila@oncogenome.gr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with histologically confirmed HR-positive, HER2-negative breast cancer treated with abemaciclib in combination with endocrine therapy

Description

Inclusion Criteria:

• Histologically confirmed HR-positive, HER2-negative breast cancer
• Treated at Hellenic Cooperative Oncology Group (HeCOG)-affiliated departments of oncology
• 18 years or older
• Any menopausal status
• Treatment with abemaciclib in combination with endocrine therapy
• Any endocrine therapy
• At least two months of treatment with abemaciclib

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Patients with breast cancer randomised in arm A of digital platform; Patients with breast cancer treated with abemaciclib in combination with endocrine treatment and randomised in Arm A of the digital platform. Patients randomised in arm A will receive a an acknowledgement and suggestion to stay in contact with their clinician.
Patients with breast cancer randomised in arm B of digital platform; Patients with breast cancer treated with abemaciclib in combination with endocrine treatment and randomised in Arm B of the digital platform. Patients randomised in arm A will receive a an acknowledgement and suggestion to stay in contact with their clinician; additionally they will receive personalised support (as a few word text) for each side-effect reported.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression-free survival	the time from treatment initiation to either the first documented disease progression or death from any cause	Through the completion of the study, for an average of 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall survival	The time from treatment initiation to patient death or last contact	From date of treatment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 96 months
Efficacy of the digital support through personalised support in patients with BC		Up to 30 months
Toxicity rate	Adverse events from the time from treatment initiation to disease progression, patient death or last contact	Up to 30 months

Collaborators and Investigators

• Sponsor: Hellenic Cooperative Oncology Group

Publications and helpful links

General Publications

• Fountzilas E, Aravantinou-Fatorou E, Dadouli K, Economopoulou P, Tryfonopoulos D, Vernadou A, Vorrias E, Vagionas A, Nikolaidi A, Karageorgopoulou S, Koumarianou A, Boukovinas I, Mauri D, Kokkali S, Christopoulou A, Tsoukalas N, Assi A, Spathas N, Kosmidis P, Koutras A, Fountzilas G, Psyrri A. Real-World Toxicity and Effectiveness Study of Abemaciclib in Greek Patients with Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer: A Multi-Institutional Study. Cancers (Basel). 2025 Jul 31;17(15):2543. doi: 10.3390/cancers17152543.

Study record dates

Study Major Dates

• Study Start (Actual): October 6, 2021
• Primary Completion (Estimated): November 30, 2026
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: July 26, 2021
• First Submitted That Met QC Criteria: July 26, 2021
• First Posted (Actual): August 2, 2021

Study Record Updates

• Last Update Posted (Actual): July 21, 2026
• Last Update Submitted That Met QC Criteria: July 20, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: abemaciclib; real-world data
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms
• Other Study ID Numbers: ΗΕ_11ΑΒ/21

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No