The Impact of an Antibiotic (Cefazolin) Before Surgery on the Microbiome in Patients With Stage I-II Melanoma
Clinical Stage I Cutaneous Melanoma AJCC v8 · Clinical Stage IA Cutaneous Melanoma AJCC v8 · Clinical Stage IB Cutaneous Melanoma AJCC v8 · Clinical Stage II Cutaneous Melanoma AJCC v8 · Clinical Stage IIA Cutaneous Melanoma AJCC v8 · Clinical Stage IIB Cutaneous Melanoma AJCC v8 · Clinical Stage IIC Cutaneous Melanoma AJCC v8 · Pathologic Stage I Cutaneous Melanoma AJCC v8 · Pathologic Stage IA Cutaneous Melanoma AJCC v8 · Pathologic Stage IB Cutaneous Melanoma AJCC v8 · Pathologic Stage II Cutaneous Melanoma AJCC v8 · Pathologic Stage IIA Cutaneous Melanoma AJCC v8 · Pathologic Stage IIB Cutaneous Melanoma AJCC v8 · Pathologic Stage IIC Cutaneous Melanoma AJCC v8
What this study involves
The registry does not currently label this study as recruiting. Ask about its status before planning a screening visit.
- Study type
- Interventional
- Phase
- Phase 1
- Age range
- 18 years - Not specified
- Sex eligible
- All sexes
- Healthy volunteers
- Not accepted
- Participants
- 20 Estimated
These are starting points, not an eligibility decision. The research team must review the full requirements.
About the research
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.
Read the full 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.
Who may be able to participate?
The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.
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
Treatment, groups and participation
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- Assignment
- Random assignment
- Masking
- No masking
Arm A (cefazolin, surgical resection)
Patients receive cefazolin IV and then undergo standard of care surgical resection within 1 hour.
Drug: Cefazolin · Procedure: Resection
Arm B (surgical resection)
Patients undergo standard of care surgical resection.
Procedure: Resection
Cefazolin DRUG
Given IV
Resection PROCEDURE
Undergo standard of care surgical resection
What researchers are measuring
Outcome measures describe what is being studied. They are not proof that a treatment works.
Primary measures
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.
Secondary measures
Change in relative abundance of microbes
Time frame: Baseline, at 2 weeks post-surgery, and 3 months post-surgery
Not reported in this registry record.
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.
Wound (surgical site) infection rate
Time frame: Up to 3 months post-surgery
Not reported in this registry record.
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.
Review the complete result tables and limitations in the official record.
Open official results ↗Research locations (1)
The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.
1 locations
M D Anderson Cancer CenterHouston, Texas, United StatesStatus unknown
Study team and timeline
- Lead sponsor
- M.D. Anderson Cancer Center
- Study start
- Sep 8, 2020 Actual
- Primary completion
- Feb 2, 2027 Estimated
- Study completion
- Feb 2, 2027 Estimated
- First posted
- May 6, 2021 Actual
- Last updated
- Nov 10, 2026 Actual
Official study contacts
No central contact is listed. Check the locations and the official record.
Official study title
Evaluating the Impact of Perioperative Antibiotic Prophylaxis on the Microbiome in Patients With Cutaneous Malignancy
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Source: ClinicalTrials.gov API v2. Information is submitted by sponsors and investigators. NLM does not approve the safety or science of all listed studies. Registry disclaimer.
Retrieved: Nov 11, 2026 · Last registry update: Nov 10, 2026