Skip to main content
Future Oncology logoLink to Future Oncology
. 2024 Jul 18;20(28):2037–2048. doi: 10.1080/14796694.2024.2362095

Abemaciclib plus endocrine therapy for HR+, HER2-, node-positive, high-risk early breast cancer: a plain language summary of the monarchE study

Stephen R D Johnston a, Hope S Rugo b, Sara M Tolaney c, Maria Munoz Fernandez d, Ran Wei d, Miguel Martin e
PMCID: PMC11500823  PMID: 39023253

Summary

What is this summary about?

This article summarizes the most recent results of the monarchE study. This study was completed in participants with a type of breast cancer called HR+, HER2-, node-positive, high-risk early breast cancer. In this study, abemaciclib, a non-chemotherapy treatment, was administered with standard of care endocrine therapy after curative surgery. Most participants had received prior chemotherapy and/or radiotherapy. The study investigated if abemaciclib helped participants live longer without their cancer returning compared with participants who only received standard of care endocrine therapy. The study participants were assigned to 1 of 2 treatment groups. Participants in Group A were assigned to receive standard of care endocrine therapy with abemaciclib for 2 years, followed by endocrine therapy for a total of at least 5 years. Participants in Group B were assigned to receive standard of care endocrine therapy only for at least 5 years. The effect of treatment was compared between these 2 groups.

What were the results?

Overall, the results showed that the cancer was 34% less likely to come back after surgery in the participants in Group A (abemaciclib plus endocrine therapy) compared with those in Group B (endocrine therapy only). At 4 years since the start of the study treatment, more participants who received the combination of abemaciclib plus endocrine therapy remained free of cancer compared with participants who received endocrine therapy alone (86% versus 79%). Participants who received abemaciclib plus endocrine therapy had more side effects than those who received endocrine therapy alone, but most of these effects were mild to moderate and reversible upon the end of therapy. The most common side effects in the abemaciclib group were diarrhea, infections, low number of white blood cells, and tiredness.

What do the results mean?

This study found that administering abemaciclib in combination with standard endocrine therapy after curative breast surgery helped lower the risk of cancer returning in people with HR+, HER2-, node-positive, high-risk early breast cancer. Abemaciclib is a new treatment option for people with this diagnosis. People with high-risk early breast cancer should always talk to their doctors and nurses before making any decisions about their treatment.

Clinical Trial Registration: NCT03155997 (monarchE study)

Keywords: : abemaciclib, breast cancer, endocrine therapy, lay summary, monarchE, plain language summary


This is an abstract of the Plain Language Summary of Publication article.

To read the full Plain Language Summary of this article, click here to view the PDF.

Link to original article here Link to original article here

The original article from The Lancet Oncology can be accessed here.

The second original article can be accessed here and was published in Annals of Oncology, Vol 33, H.S. Rugo, J. O'Shaughnessy, F. Boyle, M. Toi, R. Broom, I. Blancas, M. Gumus, T. Yamashita, Y.-H. Im, P. Rastogi, F. Zagouri, C. Song, M. Campone, B. San Antonio, A. Shahir, M. Hulstijn, J. Brown, A. Zimmermann, R. Wei, S.R.D. Johnston, M. Reinisch, S.M. Tolaney, Adjuvant abemaciclib combined with endocrine therapy for high-risk early breast cancer: safety and patient-reported outcomes from the monarchE study, Pages 616–627, Copyright Elsevier (2022).

Acknowledgments

We thank the 5637 participants and their families/caregivers from 603 sites in 38 countries for participating in this study. We are grateful for the investigators and their support staff who generously participated in this work.

Financial disclosure

The monarchE study was sponsored by Eli Lilly and Company. Eli Lilly and Company funded the medical writing support and journal publishing costs of this plain language summary of publication. Dr Johnston reports honoraria for Pfizer, Novartis, Eisai, AstraZeneca, Roche, Eli Lilly; consulting or advisory role for Eli Lilly, Puma Biotechnology, Novartis, Pfizer; research funding for Pfizer, Puma Biotechnology. Dr Rugo reports consulting or advisory role for Napo Pharmaceuticals, Scorpion Therapeutics, Blueprint Medicines, Puma Biotechnology; research funding for OBI Pharma, Pfizer, Novartis, Lilly, Genentech, Merck, Daiichi Sankyo, Sermonix Pharmaceuticals, AstraZeneca, Gilead Sciences, Astellas Pharma, Pionyr, Taiho Oncology, GlaxoSmithKline; travel, accommodations, expenses for Merck, AstraZeneca, Gilead Sciences. Dr Tolaney reports research funding for AstraZeneca, Lilly, Merck, Nektar, Novartis, Pfizer, Genentech/Roche, Immunomedics/Gilead, Exelixis, Bristol-Myers Squibb, Eisai, Nanostring, Cyclacel, Odonate, and Seattle Genetics; consulting or advisory role for AstraZeneca, Eli Lilly, Merck, Nektar, Novartis, Pfizer, Genentech/Roche, Immunomedics/Gilead, Bristol-Myers Squibb, Eisai, Nanostring, Puma, Sanofi, Silverback Therapeutics, G1 Therapeutics, Athenex, OncoPep, Kyowa Kirin Pharmaceuticals, Daiichi-Sankyo, Ellipsis, Infinity, 4D Pharma, and Samsung Bioepsis Inc., Chugai Pharmaceuticals, BeyondSpring Pharmaceuticals, OncXerna, OncoSec Medical Incorporated, Certara, Mersana Therapeutics, CytomX, Seattle Genetics. Dr Munoz Fernandez reports employment and stock/ownership interests for Eli Lilly. Dr Wei reports employment and stock/ownership interests for Eli Lilly. Dr Martin reports honoraria for Roche/Genentech, Lilly, Pfizer, Novartis, Pierre Fabre, Seagen; consulting or advisory role for Roche/Genentech, Novartis, Pfizer, Lilly, AstraZeneca, Daiichi Sankyo; speakers' bureau for Lilly/ImClone, Roche/Genentech, Pierre Fabre 19; research funding for Novartis, Roche, Puma Biotechnology; Travel, Accommodations, Expenses for Daichii-Sankyo; other relationships for Roche, Novartis. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Competing interests disclosure

The authors have no competing interests or relevant affiliations with any organization or entity with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, stock ownership or options and expert testimony.

Writing disclosure

Maeve O'Connell, PhD, of Eli Lilly and Company, provided medical writing support and Praveen Shetty of Eli Lilly Services India Private Limited, provided graphical design support for this plain language summary of publication.


Articles from Future Oncology are provided here courtesy of Taylor & Francis

RESOURCES