Water-only fasting to improve chemotherapy for early-stage breast cancer

Gut Microbiome, Adverse Effects, and Markers Through MEtabolic Reprogramming (GAMMER) Study in Early Stage Breast Cancer Receiving Chemotherapy

Not applicable Interventional Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins · NCT06536881

This study is testing if fasting for 24-48 hours can help make chemotherapy work better and be easier to tolerate for people with early-stage breast cancer.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years and up
SexFemale
SponsorSidney Kimmel Comprehensive Cancer Center at Johns Hopkins Academic / other
Drugs / interventionschemotherapy, prednisone, Cyclophosphamide, doxorubicin
Locations1 site (Washington D.C., District of Columbia)
Trial IDNCT06536881 on ClinicalTrials.gov

What this trial studies

This research aims to evaluate the feasibility of implementing 24-48 hours of water-only fasting to enhance the delivery of chemotherapy in patients with early-stage breast cancer. The study focuses on understanding how fasting may mitigate the adverse effects associated with chemotherapy, which often lead to dose reductions or treatment discontinuation. By examining the biological mechanisms behind fasting and its impact on chemotherapy tolerability, the study seeks to provide insights that could improve treatment outcomes for breast cancer patients. A total of 30 patients will be enrolled to assess the safety and effectiveness of this fasting intervention alongside standard chemotherapy regimens.

Who should consider this trial

Good fit: Ideal candidates are women diagnosed with stage I-III invasive breast cancer who are planning to undergo standard neoadjuvant or adjuvant chemotherapy.

Not a fit: Patients with a BMI below 19.5 kg/m2, diabetes, or serious uncontrolled medical conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could help patients tolerate chemotherapy better, potentially leading to improved treatment completion rates and outcomes.

How similar studies have performed: Preliminary studies have shown that fasting around chemotherapy is safe and may reduce expected toxicities, suggesting a promising avenue for further exploration.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Diagnosed with histologically-confirmed stage I-III invasive carcinoma of the breast
* Planning for standard neoadjuvant or adjuvant chemotherapy ddAC or TC for 4 cycles (concurrent anti-HER2 therapy is permitted)
* Provider physical exam within 4 weeks of consent
* Eastern Cooperative Oncology Group (ECOG) 0-1 (as per recent provider note or direct confirmation with provider)
* BMI ≥ 19.5 kg/m2 (as per most recent visit documented in medical record)
* Willingness to change diet, and provide fecal sample 3 times during study

Exclusion Criteria:

* BMI \<19.5 kg/m2
* Diabetes
* History of eating disorder
* Serious/uncontrolled medical condition (e.g. end stage renal disease on dialysis, cirrhosis, uncontrolled hypertension, seizure disorder, history of bariatric surgery)
* Pregnant or nursing
* Use of medications that must be taken with food: allopurinol, aspirin, amiodarone, baclofen, bromocriptine, carvedilol, carbamezpine, cimetidine, diclofenac, doxycycline, fenofibrate, fludrocortisone, glyburide, hydrocortisone, iron supplements, ketorolac, lithium, methylprednisolone, naproxen, niacin, potassium salts, prednisone, procainamide, sevelamer, sulfasalazine, trazodone, valproic acid

Where this trial is running

Washington D.C., District of Columbia

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Breast CancerEarly-stage Breast Cancer
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.