The Impact of an Antibiotic (Cefazolin) Before Surgery on the Microbiome in Patients With Stage I-II Melanoma

May 18, 2026 updated by: M.D. Anderson Cancer Center

Evaluating the Impact of Perioperative Antibiotic Prophylaxis on the Microbiome in Patients With Cutaneous Malignancy

This phase I trial investigates the impact of cefazolin before surgery on the microbiome in patients with stage I-II melanoma. Antibiotics, such as cefazolin, given at the time of surgery may cause a significant change in the microbes (like bacteria and viruses) found in the stomach and intestines. This trial may help researchers learn if any changes in microbes affect the body's ability to respond to surgery and cancer.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

PRIMARY OBJECTIVE:

I. To investigate whether the use of pre-operative prophylactic antibiotics administered during surgical resection substantially alters the patient's gut microbiome.

SECONDARY OBJECTIVES:

I. To characterize the dynamics of the immune response to surgical intervention in the absence and presence of pre-operative prophylactic antibiotics, focusing on the immune profile of the peripheral blood leukocytes as well as the balance of circulating pro- and anti-inflammatory cytokines and metabolomic profiles.

II. To assess surgical site infection (SSI) in the absence and presence of pre-operative prophylactic antibiotics at time of surgical resection.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM A: Patients receive cefazolin intravenously (IV) and then undergo standard of care surgical resection within 1 hour.

ARM B: Patients undergo standard of care surgical resection.

After completion of study treatment, patients are followed up at 3 days, 2 weeks, and 3 months.

Study Type

Interventional

Enrollment (Estimated)

20

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Texas
      • Houston, Texas, United States, 77030
        • M D Anderson Cancer Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

14 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adult subjects with early stage melanoma (stage I-II)
  • Patients must be undergoing wide local excision +/- sentinel lymph node biopsy
  • Patients must be capable of giving written informed consent, which includes compliance with the requirements and restrictions listed in the consent form

Exclusion Criteria:

  • Use of antibiotics within the three months prior to surgery
  • Allergy, sensitivity or anaphylaxis to beta-lactam or cephalosporin antibiotics
  • Presence of an infection at the time of surgery
  • Increased risk of infection due to a co-existing medical condition as determined by the surgical team or principal investigator (PI)
  • Subjects with a condition requiring systemic treatment with either corticosteroids (> 10 mg daily prednisone equivalents) or other immunosuppressive medications within 14 days of study drug administration
  • American Society of Anesthesiologists (ASA) grade > IV
  • Refusal to participate in the study
  • Patients who are pregnant will not be included in this study

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Arm A (cefazolin, surgical resection)
Patients receive cefazolin IV and then undergo standard of care surgical resection within 1 hour.
Drug: Cefazolin
Given IV
Procedure: Resection
Undergo standard of care surgical resection
Other Names:
  • Surgical Resection
Experimental: Arm B (surgical resection)
Patients undergo standard of care surgical resection.
Procedure: Resection
Undergo standard of care surgical resection
Other Names:
  • Surgical Resection

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in microbiome alpha diversity
Time Frame: Baseline up to 2 weeks post-surgery
The diversity, structure, and composition of the fecal microbiome will be determined by 16S(v4) rRNA gene sequencing. 16S profiles will be used to compute alpha diversity, beta diversity, and the relative abundance of fecal bacteria. The composition of fecal bacteria in adult humans is mainly dominated by members of the Firmicutes and Proteobacteria phyla while members of Proteobacteria, Actinobacteria, Fusobacteria, and Verrucomicrobia are observed in lower abundance. To calculate richness (alpha-diversity), we will count each operational taxonomic unit (OTU) or amplicon sequence variant (ASV) identified. Richness count is expected to range between 10-500 per sample.
Baseline up to 2 weeks post-surgery

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in relative abundance of microbes
Time Frame: Baseline, at 2 weeks post-surgery, and 3 months post-surgery
Baseline, at 2 weeks post-surgery, and 3 months post-surgery
Change in microbiome diversity
Time Frame: Baseline up to 3 months post-surgery
The diversity, structure, and composition of the fecal microbiome will be determined by 16S(v4) rRNA gene sequencing. 16S profiles will be used to compute alpha diversity, beta diversity, and the relative abundance of fecal bacteria. The composition of fecal bacteria in adult humans is mainly dominated by members of the Firmicutes and Proteobacteria phyla while members of Proteobacteria, Actinobacteria, Fusobacteria, and Verrucomicrobia are observed in lower abundance. To calculate richness (alpha-diversity), we will count each operational taxonomic unit (OTU) or amplicon sequence variant (ASV) identified. Richness count is expected to range between 10-500 per sample.
Baseline up to 3 months post-surgery
Wound (surgical site) infection rate
Time Frame: Up to 3 months post-surgery
Up to 3 months post-surgery
Profiling of systemic immune function by analysis of composition of circulating immune cell populations and cytokines
Time Frame: Up to 3 months post-surgery
By analysis of composition of circulating immune cell populations and cytokines.
Up to 3 months post-surgery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

M.D. Anderson Cancer Center

Collaborators

National Cancer Institute (NCI)

Investigators

  • Principal Investigator: Emily Z Keung, M.D. Anderson Cancer Center

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 8, 2020

Primary Completion (Estimated)

February 2, 2027

Study Completion (Estimated)

February 2, 2027

Study Registration Dates

First Submitted

October 5, 2020

First Submitted That Met QC Criteria

May 3, 2021

First Posted (Actual)

May 6, 2021

Study Record Updates

Last Update Posted (Actual)

May 20, 2026

Last Update Submitted That Met QC Criteria

May 18, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2020-0265 (Other Identifier: M D Anderson Cancer Center)
  • NCI-2020-07071 (Registry Identifier: CTRP (Clinical Trial Reporting Program))

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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