Comparing antibiotic dosing methods for overweight surgical patients

Comparison of a Morphomic-Based to the Standard-of-Care-Based Cefazolin Dose for Antimicrobial Prophylaxis

PHASE4 · University of Michigan · NCT06005168

This study is testing if giving a different dose of an antibiotic based on body composition helps overweight surgical patients avoid infections better than the usual weight-based dosing.

Quick facts

PhasePHASE4
Study typeInterventional
Enrollment104 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Michigan (other)
Locations1 site (Ann Arbor, Michigan)
Trial IDNCT06005168 on ClinicalTrials.gov

What this trial studies

This clinical study aims to compare the effectiveness of cefazolin dosing based on body composition versus the standard body weight-based dosing in overweight patients undergoing surgery. The researchers will analyze antibiotic concentrations in blood and fat tissue to determine if the morphomic-based dosing can improve infection prevention. Participants will provide small samples of blood and fat tissue during their scheduled surgeries, allowing for a direct comparison of antibiotic exposure. The study builds on previous findings that suggest obesity may lead to suboptimal antibiotic levels, increasing the risk of surgical site infections.

Who should consider this trial

Good fit: Ideal candidates for this study are adults over 18 years old with a Body Mass Index of 25 kg/m² or higher who are scheduled for surgery and expected to receive cefazolin.

Not a fit: Patients with a history of hypersensitivity to penicillin or cephalosporin, or those who are pregnant, will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved antibiotic dosing strategies that reduce infection rates in overweight surgical patients.

How similar studies have performed: Previous studies have indicated that morphomic measurements can predict antibiotic exposure better than traditional methods, suggesting a promising avenue for further exploration.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Accessible abdominal computed tomography scan prior to surgery
2. Adult patients \> 18 years of age
3. Body Mass Index ≥ 25 kg/m\^2
4. Expected to receive cefazolin prior to surgical incision
5. Estimated creatinine clearance ≥90 mL/min

Exclusion Criteria:

1. History of a hypersensitivity reaction to penicillin or cephalosporin
2. Pregnancy

Where this trial is running

Ann Arbor, Michigan

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Surgical Prophylaxis, Pharmacokinetics, Cefazolin, Obesity, Morphomics, Colorectal

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.