Recruiting
Phase 2

Antibiotics with Treatment

Sponsor:

Virginia Commonwealth University

Code:

NCT06728072

Conditions

Colorectal Cancer

CRC

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Standard of Care Chemotherapy + Metronidazole, ciprofloxacin, aspirin

Study Details

Brief summary:

This is a 2-arm, noncomparative phase 2 trial designed to evaluate treatment outcomes with or without the addition of ciprofloxacin, metronidazole, and aspirin to first-line chemotherapy for patients with stage IV colorectal cancer (CRC).

Conditions

Colorectal Cancer

CRC

Study ID

NCT06728072

Start date

Mar 7, 2025

Status verified date

Aug, 2026

Completion date

Jul 1, 2035

Anticipated

Primary completion date

Jul 1, 2035

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Diagnosis of stage IV colorectal cancer
  • Measurable disease by Response evaluation criteria in solid tumors (RECIST) 1.1 criteria
  • Planned first-line treatment with a 5FU-based doublet chemotherapy regimen for colon cancer, specifics of the regimen at the discretion of the treating physician Note: Patients who have received adjuvant therapy >6 months prior are eligible
  • Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-2
  • Absolute neutrophil count (ANC) ≥1,500 cells/μL
  • Platelet count ≥100,000 cells/μL
  • Hemoglobin ≥8 g/dL Note: The use of transfusion or other intervention to achieve hemoglobin ≥8 g/dL is acceptable.
  • Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5 × upper limit of normal (ULN) Note: Patients with documented liver metastases: AST and ALT ≤5 × ULN
  • Serum creatinine ≤1.5 x ULN or calculated creatinine clearance ≥40 mL/min using the Cockcroft-Gault equation: (140 - age) × body weight/plasma creatinine × 72 (× 0.85 if female)
  • Radiographically measurable disease by RECIST 1.1
  • Nonpregnant and not actively breastfeeding
  • Sexually active patients of childbearing potential and their partners must agree to use medically acceptable form of contraception, per treating investigator, throughout the study Patients should continue to use medically acceptable methods of contraception after study treatment ends, following the guidance for their specific chemotherapy regimen.

Childbearing potential excludes:

Age > 50 years and naturally amenorrhoeic for > 1 year OR previous hysterectomy or bilateral salpingo-oophorectomy

  • Patients on a pre-existing daily aspirin regimen may participate in the study without interrupting this regimen.
  • Patients with a contraindication to aspirin may participate in the study. These patients will not be required to take aspirin as part of the study treatment.

Exclusion Criteria:

  • Total colectomy
  • Diagnosed with Cockayne Syndrome
  • Using disulfiram, tizanidine, or theophylline and unable to stop taking these medications for the length of the microbiome modulation therapy
  • On methotrexate doses of 15 mg/week or more
  • History of allergic reaction to ciprofloxacin, metronidazole, or aspirin
  • Fuss course of antibiotics in the 30 days before chemotherapy start Note: Full course is defined as ≥5 doses with an intent to treat a defined infection. Use of antibiotics intended for prophylaxis at the time of surgery is allowed
  • Corrected QT interval (QTc) >480 on baseline ECG
  • Diagnosed with a malabsorptive syndrome
  • Inability to swallow tablets

Study Design

Enrollment

97 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

no intervention: Standard of care

First line chemotherapy as directed. Standard of care chemotherapy treatment options include but are not limited to the following:

  • FOLFOX every 2 weeks
  • FOLFIRI every 2 weeks
  • FOLFOX + bevacizumab or panitumumab every 2 weeks
  • FOLFIRI + bevacizumab or panitumumab every 2 weeks
  • CAPEOX every 3 weeks
  • CAPEOX + bevacizumab or panitumumab every 3 weeks

experimental: Metronidazole Ciprofloxacin and Aspirin Therapy

First line chemo therapy (standard of care) + Microbiome modulation therapy MBMT 500 mg metronidazole 3 times daily, 500 mg ciprofloxacin twice daily, and 81 mg aspirin once daily for 28 days

Interventions

Standard of Care Chemotherapy + Metronidazole, ciprofloxacin, aspirin

Metronidazole, ciprofloxacin, aspirin is initiated Cycle 1 Day 1 of chemotherapy. May be initiated any time from 7 days before Cycle 1 Day 1 up to and including Cycle 1 Day 3

Primary outcome measure

  • Best response by analysis using Response Evaluation Criteria in Solid Tumors [ Time Frame: Up to 5 years ]

Central Contacts and Locations

Central contacts

Massey IIT Research Operations

804-628-6430masseyepd@vcu.edu

Locations

Virginia Cancer Institute (VCI)

Recruiting

Richmond, Virginia, United States, 23229

Contacts

Sue Moore, MSN, CNS

804-397-9640smoore@vacancer.com

Principal Investigator:

Purvi Shah, MD

Virginia Commonwealth University

Recruiting

Richmond, Virginia, United States, 23298

Contacts

Massey CTO GI Team

804-628-6430masseygi@vcu.edu

Principal Investigator:

Emily Kinsey, MD

More Information

Sponsor

Virginia Commonwealth University

Last update posted

Aug 18, 2026

Last verified

Aug, 2026

Keywords

  • Colorectal Cancer
  • CRC

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Virginia Commonwealth University on 2026-08-18.