MINDACT (BIG 3-04): an international genomic-based de-escalation trial
Updated long-term MINDACT study results confirm the clinical utility of MammaPrint® to identify patients with early breast cancer who may safely avoid chemotherapy.
From 29 until 31 May 2020, the American Society of Clinical Oncology (ASCO) organised the ASCO20 Virtual Scientific Programme, an on-line edition of the ASCO Annual Meeting, which could not take place due to the Covid-19 pandemic. This international on-line conference brought together oncology professionals from around the world, who presented and discussed state-of-the-art treatment modalities, new therapies, clinical trials, and ongoing controversies in the field of cancer.
Dr Fatima Cardoso, MD, medical oncologist and Director of the Breast Unit of the Champalimaud Clinical Center (Lisbon, Portugal), and Study Co-Chair of the MINDACT trial, presented updated results with longer patient follow-up, confirming the clinical utility of the 70-gene signature MammaPrint for post-surgery chemotherapy.
MINDACT & MammaPrint: de-escalation of post-surgery chemotherapy
In the MINDACT de-escalation trial, researchers showed that approximately half of the patients with early stage breast cancer, those whose tumours were classified as clinically high-risk but genomically low-risk (C-High/G-Low) according to MammaPrint (a sophisticated test analysing 70 genes), could safely avoid chemotherapy and its side effects.
The study, published in 2016 in the New England Journal of Medicine, is one of a series of completed and ongoing trials investigating how drug therapy may be more effectively tailored to patient needs.
Dr Fatima Cardoso, MINDACT Study Co-Chair, says: “The updated long-term results of this large prospective trial, testing the 70-gene signature MammaPrint as guidance for post-surgery chemotherapy in early-stage breast cancer patients, support our earlier conclusions and continue to provide the highest level of evidence regarding the clinical utility of MammaPrint.”
And she continues: “Our research showed that, if the genomic risk assessment is followed, chemotherapy could be avoided in about 46% of early breast cancer patients.”
She concludes: “While with longer follow-up and in line with the natural history of luminal breast cancer, more distant relapses do occur, the estimated gain of 2.6% for chemotherapy administration in patients with tumours classified as C-High / G-Low remains small in light of the harmful side effects of the chemotherapy. These results are particularly strong for postmenopausal women, where no benefit of chemotherapy within the C-High/G-Low group can be seen. For younger premenopausal women, the difference seen between chemotherapy versus no chemotherapy is now clinically significant (about 5%). However, this is probably due to an indirect effect of chemotherapy through ovarian function suppression. This must be carefully discussed with each patient for an informed shared treatment decision. Overall, these latest MINDACT study results confirm that it is possible to substantially and safely de-escalate the use of post-surgery chemotherapy, thereby sparing many patients an aggressive treatment they will not benefit from and improving their quality of life. This gives hope to many women with early stage breast cancer.”
Changing the future of breast cancer treatment
One of the main challenges in oncology today has become to accurately distinguish between patients who need post-surgery treatment and those who do not. This, together with the identification of the best type of therapy for each individual patient and the development of drugs targeting specific characteristics of tumour cells, are the goals of treatment tailoring or personalised medicine. It is our mission to find ways of ensuring patients receive the treatments most appropriate for them.
Professor David Cameron, BIG Chair: “MINDACT was a step in the direction of drug de-escalation because it used a novel diagnostic test to show that some patients who might previously have been given chemotherapy did not in fact need it. It showed that we are moving towards using the biological characteristics of a tumour to help safely exclude the need for a treatment which has previously been thought necessary.”
MINDACT is a successful example of how, by working together across borders and disciplines, we can develop better treatments while increasing the likelihood of finding cures
MINDACT demonstrates how our joining efforts have a direct impact on patients’ lives. The trial is sponsored and run by the European Organisation for Research and Treatment of Cancer (EORTC) under the Breast International Group (BIG) umbrella, and many other partners, both from academia and the private sector, including the breast cancer patient advocacy network Europa Donna. The biotechnology company Agendia developed MammaPrint®.
Seven research groups from the BIG network are participating in this trial: EORTC, BOOG, GOIRC, NCRI, SOLTI, Unicancer and WSG.
Total funding: approx. EUR 47 million
MINDACT was supported by grants from the European Commission Framework Programme VI (FP6-LSHC-CT-2004-503426, “TRANSBIG Network of Excellence”), the Breast Cancer Research Foundation, Novartis, F. Hoffman La Roche, Sanofi-Aventis, Eli Lilly, Veridex, the U.S. National Cancer Institute, the European Breast Cancer Council-Breast Cancer Working Group (BCWG grant for the MINDACT biobank), the Jacqueline Seroussi Memorial Foundation (2006 JSMF award), Prix Mois du Cancer du Sein (2004 award), Susan G. Komen for the Cure (SG05-0922-02), Fondation Belge Contre le Cancer (SCIE 2005-27), Dutch Cancer Society (KWF), Association Le Cancer du Sein, Parlons-en!, the Brussels Breast Cancer Walk-Run and the American Women’s Club of Brussels, NIF Trust, Deutsche Krebshilfe, the Grant Simpson Trust and Cancer Research UK. This trial was also supported by the EORTC Charitable Trust. Whole genome analysis was provided in kind by Agendia.