Recruiting NCT07624617
Fast-Her: Fasting Effects on Breast Cancer Treatment
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Normal Eating, Prolonged Fasting.
- Who it may be relevant to
- Registry conditions: Metastatic Breast Cancer. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Overview
We hypothesize that promoting a fasting state will strengthen the anti-cancer effects of PI3K inhibitors in metastatic breast cancer (MBC) treatment. The primary objective of this study is to assess acceptability of prolonged fasting in this population.
Interventions
- Behavioral Normal Eating
During the normal eating intervention period, participants will follow their usual eating pattern. Participants will continue their prescribed PI3K inhibitor dosing, with medications taken at standardized times to ensure consistent pharmacokinetic measurements. - Behavioral Prolonged Fasting
During the prolonged fasting intervention period, participants will eat only once daily (dinner), with water, black coffee, and tea permitted during fasting hours. Participants will continue their prescribed PI3K inhibitor dosing, with medications taken at standardized times to ensure consistent pharmacokinetic measurements.
Primary outcome measures
- Effect of plasma from fasting in patients on PI3K inhibitors on cell viability [Time frame: Week 2 of prolonged fasting]
- mechanisms by which fasting might enhance PI3K inhibitor efficacy through complementary molecular and cellular studies [Time frame: Week 7]
- Identify biomarkers/patient characteristics predicting the enhancement of PI3K inhibitor efficacy with fasting. [Time frame: Week 7]
Eligibility criteria
Inclusion criteria
- Age ≥18 years
- Histologically confirmed metastatic breast cancer
- Menopausal or medically ovarian suppressed
- Currently receiving capivasertib therapy (2 tablets twice daily, 4 days per week)
- Stable on current capivasertib regimen for at least 2 weeks
- an ECOG performance status of 0-1
- BMI ≥25kg/m2
- Able to provide informed consent
- Willing to comply with study procedures including CGM wear, food tracking by mCC app and dietary modifications
- Access to smartphone or tablet for mobile application use
Exclusion criteria
- Type 1 diabetes mellitus
- Uncontrolled type 2 diabetes (HbA1c >9.0%)
- History of severe hypoglycemia
- Eating disorders or contraindications to fasting
- Pregnancy or breastfeeding
- Significant gastrointestinal disorders affecting food absorption
- Unable to fast for medical reasons
- Concurrent participation in other dietary intervention studies
- A history of significantly abnormal lab results within 4 weeks of consent date, such as hematologic (Hgb < 10.0, platelets < 100), hepatic (LFTs > 2X nl), renal (Cr > 1.5)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Open label
- Primary purpose
- Supportive care
Study locations
United States · 1 center
- University of Minnesota — Minneapolis
Identifiers
NCT: NCT07624617 · MED-2025-34235