Antibiotic Tissue Penetration and Tissue Response in Head and Neck Infection and Reconstructive Surgery (ANTIBIOTIKA)

November 1, 2026 updated by: Tejs Ehlers Klug

Antibiotic Penetration and Tissue Response in Infection and Reconstructive Surgery of the Head and Neck Region: A Microdialysis Study of Cefuroxime, Cloxacillin, Dicloxacillin, and Amoxicillin/Clavulanic Acid

The goal of this study is to measure how well commonly used antibiotics reach the tissue in the head and neck region in adults with a postoperative neck infection or undergoing reconstructive nasal surgery with an inferior turbinate flap. The study also describes markers of ischemia and inflammation in the newly created flap during the first days after surgery.

The main question it aims to answer is: For how long do the free concentrations of cefuroxime, cloxacillin, dicloxacillin, and amoxicillin/clavulanic acid stay above the minimal inhibitory concentration (T>MIC) in infected tissue, non-infected tissue, the flap, and plasma?

Participants will receive the antibiotics on a fixed, protocol-defined schedule for about two days. Small microdialysis catheters will be placed in the tissue to collect fluid continuously, and serial blood samples will be drawn. Participation ends when the last sample is collected and the catheters are removed.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Infections in the head and neck region and reconstructive surgery in the nasal and sinus area are associated with considerable morbidity and require effective antibiotic treatment. Treatment is based mainly on systemic antibiotic concentrations, but little is known about actual tissue penetration in infected tissue and in reconstructed flaps, where perfusion, edema, ischemia, and inflammation may alter drug distribution. Microdialysis is a minimally invasive method for continuous sampling of free, pharmacologically active drug concentrations and metabolic and inflammatory markers in the extracellular fluid.

This is a prospective, non-randomized, open-label, exploratory interventional study with two sub-studies and a total of 16 participants. All study drugs are marketed antibiotics used in routine clinical practice; they are administered in a protocol-defined regimen to allow pharmacokinetic sampling.

Sub-study 1 (n=8): Adults admitted with a postoperative infection in the neck. Treatment is started on day 1 with cefuroxime 750 mg IV four times daily and dicloxacillin 1000 mg orally four times daily. On day 2, microdialysis catheters are placed in infected and non-infected subcutaneous tissue of the neck, and sampling is performed over two consecutive dosing intervals: (1) cefuroxime 750 mg IV plus dicloxacillin 1000 mg orally, sampled for 6 hours; and (2) cefuroxime 1500 mg IV plus cloxacillin 1000 mg IV, sampled for 8 hours. This allows comparison of two cefuroxime doses and of oral dicloxacillin versus intravenous cloxacillin.

Sub-study 2 (n=8): Adults undergoing reconstructive surgery with an inferior turbinate flap (IFT flap). Postoperatively, amoxicillin/clavulanic acid 500/125 mg and dicloxacillin 1000 mg are given orally three times daily. Microdialysis catheters are placed in the flap and in the nasal septal mucosa (reference tissue). Ischemia markers (glucose, lactate, pyruvate, glycerol) and inflammatory proteins are sampled hourly during the first 6 postoperative hours and in the morning and evening of day 2. Antibiotic concentrations are measured over one dosing interval after the morning dose on day 2.

In both sub-studies, dialysate is collected in 30-60 minute intervals and serial blood samples are drawn for plasma concentrations. Catheters are calibrated in vivo at the end of sampling. Drug concentrations are analysed by LC-MS. Clinically indicated treatment can be changed by the treating physician at any time.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
16

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

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

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

  • Name: Tejs Ehlers Klug, MD, DMSc
  • Phone Number: +45 51604046
  • Email: tejsklug@rm.dk

Study Locations

  • Denmark
      • Aarhus N, Denmark, 8200
        • Recruiting
        • Aarhus University Hospital, Department of Otorhinolaryngology, Head and Neck Surgery

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Signed informed consent
  • Either a postoperative infection in the neck (sub-study 1) or planned reconstruction with an inferior turbinate flap (sub-study 2)
  • Age 18 years or older

Exclusion Criteria:

  • Known allergy or hypersensitivity to any of the study antibiotics (cefuroxime, cloxacillin, dicloxacillin, or amoxicillin/clavulanic acid)
  • eGFR below 30 mL/min/1.73 m2
  • Pregnancy or planned pregnancy

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: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Sub-study 1: Postoperative Neck Infection

Adults with a postoperative infection in the neck (n=8). Cefuroxime 750 mg IV four times daily and dicloxacillin 1000 mg orally four times daily from day 1. On day 2, microdialysis in infected and non-infected subcutaneous tissue over two consecutive dosing intervals: (1) cefuroxime 750 mg IV + dicloxacillin 1000 mg orally (6 hours); (2) cefuroxime 1500 mg IV + cloxacillin 1000 mg IV (8 hours), with serial plasma samples.
Drug: Cefuroxime

Sub-study 1: Cefuroxime 750 mg intravenously four times daily from day 1. On day 2, one dosing interval of cefuroxime 750 mg IV (sampled over 6 hours) followed by one dosing interval of cefuroxime 1500 mg IV (sampled over 8 hours), to compare tissue penetration of the two doses.

Drug: Dicloxacillin

Dicloxacillin 1000 mg orally. Sub-study 1: four times daily from day 1, with tissue and plasma sampling during the first dosing interval on day 2 (6 hours). Sub-study 2: three times daily postoperatively from day 1, with tissue and plasma sampling over one dosing interval after the morning dose on day 2.

Drug: Cloxacillin

Sub-study 1: Cloxacillin 1000 mg intravenously as a single dose in the second dosing interval on day 2 (given together with cefuroxime 1500 mg IV), with tissue and plasma sampling over 8 hours, to compare with oral dicloxacillin.

Procedure: Microdialysis and serial blood sampling

CE-marked microdialysis catheters perfused with isotonic saline (0.5-1 microL/min) are placed in the target tissues: infected and non-infected subcutaneous neck tissue (sub-study 1), or the inferior turbinate flap and nasal septal mucosa as reference tissue (sub-study 2). Dialysate is collected in 30-60 minute intervals, with serial blood samples drawn for plasma concentrations. Catheters are calibrated in vivo at the end of sampling and then removed.
Experimental: Sub-study 2: Inferior Turbinate Flap Reconstruction

Adults undergoing reconstructive surgery with an inferior turbinate flap (n=8). Amoxicillin/clavulanic acid 500/125 mg and dicloxacillin 1000 mg orally three times daily postoperatively from day 1. Microdialysis in the flap and in nasal septal mucosa (reference tissue): ischemia markers and inflammatory proteins hourly for the first 6 postoperative hours and morning/evening on day 2; amoxicillin and dicloxacillin concentrations over one dosing interval after the morning dose on day 2, with serial plasma samples.
Drug: Dicloxacillin

Dicloxacillin 1000 mg orally. Sub-study 1: four times daily from day 1, with tissue and plasma sampling during the first dosing interval on day 2 (6 hours). Sub-study 2: three times daily postoperatively from day 1, with tissue and plasma sampling over one dosing interval after the morning dose on day 2.

Procedure: Microdialysis and serial blood sampling

CE-marked microdialysis catheters perfused with isotonic saline (0.5-1 microL/min) are placed in the target tissues: infected and non-infected subcutaneous neck tissue (sub-study 1), or the inferior turbinate flap and nasal septal mucosa as reference tissue (sub-study 2). Dialysate is collected in 30-60 minute intervals, with serial blood samples drawn for plasma concentrations. Catheters are calibrated in vivo at the end of sampling and then removed.

Drug: Amoxicillin/Clavulanic Acid

Sub-study 2: Amoxicillin/clavulanic acid 500/125 mg orally three times daily postoperatively from day 1 (together with dicloxacillin), with tissue and plasma sampling of amoxicillin over one dosing interval after the morning dose on day 2.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Time Above the Minimal Inhibitory Concentration (T>MIC) in Tissue and Plasma
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Time during which the free concentration of each study antibiotic (cefuroxime, cloxacillin, dicloxacillin, and amoxicillin/clavulanic acid) exceeds the minimal inhibitory concentration in each measured tissue (microdialysis) and in plasma (serial blood samples), calculated from concentration-time profiles. Pre-specified MIC targets: cefuroxime 4 mg/L; cloxacillin 2 mg/L; dicloxacillin 2 mg/L; amoxicillin/clavulanic acid 2 mg/L (amoxicillin component). Reported as time (hours) and as percentage of the dosing interval.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Area Under the Concentration-Time Curve (AUC) in Tissue and Plasma
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

AUC of the free concentration of each study antibiotic in each measured tissue compartment (microdialysis) and in plasma.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.
Tissue Penetration Ratio (AUC Tissue / AUC Plasma)
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Ratio of the AUC of the free antibiotic concentration in each tissue compartment to the AUC in plasma, for each study antibiotic.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.
Maximum Concentration (Cmax) in Tissue and Plasma
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Peak free concentration of each study antibiotic in each measured tissue compartment and in plasma.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.
Time to Maximum Concentration (Tmax) in Tissue and Plasma
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Time from dose administration to peak free concentration of each study antibiotic in each measured tissue compartment and in plasma.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.
Elimination Half-Life (T1/2) in Tissue and Plasma
Time Frame: Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.

Elimination half-life of each study antibiotic in each measured tissue compartment and in plasma, derived from the concentration-time profiles.
Sub-study 1: two consecutive dosing intervals on day 2 (0-6 hours and 0-8 hours after dosing). Sub-study 2: one dosing interval (approximately 8 hours) after the morning dose on postoperative day 2.
Lactate/Pyruvate Ratio in the Inferior Turbinate Flap
Time Frame: Hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2.

Lactate/pyruvate ratio measured in microdialysate from the inferior turbinate flap and the nasal septal reference tissue, as a marker of tissue ischemia (sub-study 2).
Hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2.
Tissue Ischemia Markers (Glucose, Lactate, Pyruvate, and Glycerol)
Time Frame: Sub-study 2: hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2. Sub-study 1: during the sampling period on day 2 (up to approximately 14 hours).

Concentrations of glucose, lactate, pyruvate, and glycerol in microdialysate from the measured tissue compartments.
Sub-study 2: hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2. Sub-study 1: during the sampling period on day 2 (up to approximately 14 hours).
Inflammatory Proteins in Microdialysate
Time Frame: Hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2.

Levels of inflammatory proteins measured in microdialysate from the inferior turbinate flap and the nasal septal reference tissue, to characterize the early postoperative inflammatory tissue response (sub-study 2).
Hourly during the first 6 postoperative hours (day 1), and in the morning and evening of postoperative day 2.

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Tejs Ehlers Klug

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Danish Cancer Society

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Tejs Ehlers Klug, MD, DMSc, Aarhus University Hospital

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 (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 1, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 20, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 20, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 26, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 4, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 1, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2026-526995-22-00
  • 2026-526995-22-00 (Ctis)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared publicly due to Danish and EU data protection legislation (GDPR). Aggregated results will be published in peer-reviewed journals and reported in CTIS.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

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.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings