Clinical trial · Interventional
Bacterial Intestinal Gut Modification Around Cancer Surgery (BIG MACS) Diet
NCT05658263CI-TRIAL-00089608completedEarly Phase 1ClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The long-term study objective is to develop optimized nutritional therapies for surgery and test them in clinical practice. This pilot study will test a microbiome-optimization diet in colorectal cancer surgery patients. The study hypothesizes that the Bacterial Intestinal Gut Modification Around Cancer Surgery (BIG MACS) Diet will provide participants with increased microbiota accessible carbohydrates (MACs) to support the microbiome and improve outcomes.
Conditions
Conditions (3)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Colon Cancer | Malignant Colon Neoplasm | CURATED_EXACT | 0.92 |
| Dysbiosis | — | UNRESOLVED | — |
| Sarcopenia | — | UNRESOLVED | — |
Interventions
Interventions (2)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| BIG MACS Diet | Dietary Supplement | — | UNRESOLVED |
| Standard Diet | Dietary Supplement | — | UNRESOLVED |
Design
Arms and outcomes
Arms (2)
- type
- ACTIVE_COMPARATOR
- label
- Standard Diet
- description
- Participants receiving only standard of care (SOC) nutrition advice, which is SOC Dietary Instructions, as provided by routine surgical consults and one protein shake per day for 4 weeks prior to surgery (SOC).
- interventionNames
- Dietary Supplement: Standard Diet
- type
- EXPERIMENTAL
- label
- BIG MACS Diet
- description
- Participants will be instructed to consume the study diet, referred to as the 'BIG MACS Diet' and one protein shake per day for 4 weeks prior to surgery (SOC). Following surgery, participants will continue to follow the BIG MACS Diet for an additional four weeks, with solid food reintroduction after surgery as early as tolerated.
- interventionNames
- Dietary Supplement: BIG MACS Diet
Primary outcomes (18)
Eligibility
Eligibility (as posted)
- Sex
- All
- Minimum age
- 25 Years
- Maximum age
- 70 Years
Show eligibility criteria text
Inclusion Criteria: * Age 25-70 years * Primary diagnosis of colon cancer, stages 1-3. * Able and willing to provide informed consent. * English-speaking. * Willingness to return to the study site for specified study visits at D7 and D30. * Able to comply with study measures. Exclusion Criteria: * Age ≤ 25 years or ≥70 years * If surgery is being performed for any reason other than resection of colon cancer. Neoadjuvant therapy, or if surgery is not the initial approach for the patient's colon cancer treatment * Significant anemia (hemoglobin 1.0 g/dL or more below normal range) or history of coagulopathy: any personal history of hereditary or acquired bleeding disorder, or thrombocytopenia with platelets under 100,000. * Serum creatinine greater than 1.5 mg/dL. * Serum total bilirubin greater than the upper limit of normal in the absence of Gilbert's syndrome or alkaline phosphatase or ALT or AST greater than 2.5 times the upper limit of normal. Elevated INR (1.5 or above). * Alcohol intake more than one drink or greater than 20 grams per day for women or 30 grams per day for men. * History of gastrointestinal surgery including stomach, small bowel or colon resection, pancreatic surgery, bile duct or gallbladder surgery, or splenectomy, or gastric bypass. * History of intra-abdominal sepsis. * Previous organ transplantation. * Self-reported HIV-positive status, active tuberculosis, active malaria, chronic hepatitis B or C, cirrhosis, or inflammatory bowel disease. * Currently pregnant or nursing. * History of alcohol, drug, or opioid dependency (excluding nicotine) in the past five years. * Active psychosocial or psychiatric problem that is likely to interfere with adherence to the protocol. * Depression: A CES-D score more than 16 and a psychologist determining that the patient is not a good fit for surgery. * Body mass index (BMI) \<20 or \> 40 kilograms per meter squared: obesity is known to impact the microbiome and immune system and the occurrence of anastomotic leak, and extreme obesity may confound interpretation of these factors in association to leak. Inferences may be made by matching participants with less severe obesity (BMI \<40). * Presence of any type of non-MRI compatible implant, including cardiac pacemakers or defibrillators, neurostimulators, cochlear implants, or other metallic hardware * Self-reported history of claustrophobia. * Incarceration * Inability to adhere to the study protocol, procedures, and diet * Exclusions may also be made at the discretion of the attending physician.
References
Publications (0)
Data not yet available
No reference posted for this study.