A

DIRECT2: A randomized phase III trial with a fasting mimicking diet program to improve chemotherapy in patients with hormone receptor positive, HER2-negative breast cancer—A Dutch Breast Cancer Research Group study (BOOG).

Journal of Clinical Oncology, vol. 41, pp. TPS630

Abstract

TPS630 Background: Preclinical research has shown that fasting and/or a fasting mimicking diet (FMD) in addition to chemotherapy can enhance cancer treatment effectivity and reduce side-effects. The previous DIRECT1 phase 2 study (de Groot S, Nat. Commun. 2020) indicated that FMD could increase effectivity of neoadjuvant chemotherapy in patients with HER2-negative breast cancer. Methods: DIRECT2 is a multicenter, randomized, open label phase 3 study that investigates whether FMD compared to a regular diet during neoadjuvant chemotherapy can improve the pathological and/or radiological response rate in patients with hormone receptor positive (HR+), HER2-negative, stage II/III breast cancer. Secondary endpoints include quality of life, cognition, toxicity ≥grade 3 and the immunomodulating effect of FMD. The FMD consists of a low-caloric diet of 600kcal/day starting 3 days prior to, and on the day of chemotherapy administration every 4 weeks, for a total of 5 FMD cycles during neoadjuvant chemotherapy (4 times dose dense Adriamycin plus cyclophosphamide followed by 12 times weekly paclitaxel). Patients will be supported and monitored by a centralized dietician during each FMD cycle. An additional MRI will be conducted after 4ddAC to evaluate efficacy mid-way through chemotherapy. Furthermore, an optional tumor biopsy will be done to determine the immunomodulatory effects of the FMD which will be determined using cutting-edge RNA sequencing and multispectral imaging techniques. Pathological response will be graded on the surgical specimen according to Miller & Payne 4/5, indicating a 90-100% tumor cell loss. Radiological response will be determined by MRI (RECIST1.1). In total 240 patients are needed to detect an increase from 20% to 37.5% in pathological response rate in the FMD arm allowing for 15% dropout, using a two-sided Z test with pooled variance and 5% significance level with a power of 80%. Randomization will be performed in Castor EDC with variable block sizes and stratified by clinical stage (stadium II versus III) and BMI (< 25kg/m2 versus ≥ 25kg/m2). Inclusion criteria are HR+, HER2- breast cancer stage II-III, BMI > 18.5 kg/m2, WHO status 0-2, without a history of malignancy in the past 5 years, invasive or ipsilateral non-invasive breast cancer. Patients will be excluded in case of pregnancy, lactation or metabolic disease that affects gluconeogenesis and adaptability to FMD. The trial is supported by grants from the Dutch Cancer Society and WCRF. The study is open since February 2023 for inclusion for 4 years and plans to recruit 240 patients in total in 20 participating hospitals in the Netherlands. Clinical trial information: NCT05503108 .

Authors 18

  1. Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

  2. Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

  3. The Netherlands Cancer Institute

    Affiliation as printed

    Psychosocial Research and Epidemiology, Netherlands Cancer Institute, Amsterdam, Netherlands

  4. Leiden University Medical Center

    Affiliation as printed

    Department of Surgical Oncology, Leiden University Medical Center, Leiden, Netherlands

  5. Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

  6. Chris Hinnen Aachen

    Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

  7. Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Department of Medical Statistics, Leiden, Netherlands

  8. Amphia Ziekenhuis

    Affiliation as printed

    Amphia Hospital, Breda, Netherlands

  9. Rode Kruis Ziekenhuis

    Affiliation as printed

    Rode Kruis Hospital, Beverwijk, Netherlands

  10. Jeroen Bosch Ziekenhuis

    Affiliation as printed

    Jeroen Bosch Hospital, ‘s-Hertogenbosch, Netherlands

  11. Ziekenhuis Gelderse Vallei

    Affiliation as printed

    Gelderse Vallei Hospital, Ede, Netherlands

  12. Deventer Ziekenhuis

    Affiliation as printed

    Deventer Hospital, Deventer, Netherlands

  13. VieCuri Medisch Centrum

    Affiliation as printed

    Viecuri Medical Center, Venlo, Netherlands

  14. Reinier de Graaf Hospital

    Affiliation as printed

    Reinier de Graaf, Delft, Netherlands

  15. Alexander Monro Ziekenhuis

    Affiliation as printed

    Alexander Monro Hospital, Bilthoven, Netherlands

  16. Leiden University Medical Center · Oncode Institute

    Affiliation as printed

    Department of Medical Oncology, Oncode Institute, Leiden University Medical Center, Leiden, Netherlands

  17. Hanno Pijl Aachen

    Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

  18. Leiden University Medical Center

    Affiliation as printed

    Leiden University Medical Center, Leiden, Netherlands

Cited by 1 stored of 1

1 result

No patents citing this paper on Lens.org (checked 2026-10-11).

References 0