Microbial ColonizationPhase 4NCT05515562

Effects of Intravenous (IV) Omadacycline on Gut Microbiome

A Phase 4 study testing Omadacycline Injection in people with Microbial Colonization, run by Wake Forest University Health Sciences at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

Given the clinical need to improve upon current antibiotic regimens for the treatment of C. difficile infection with a particular focus on the impact of therapies on gut microbiome, this study proposes to characterize the impact of Intravenous (IV) omadacycline on gut microbiome of healthy volunteers. Read more about this study

Who is it for?: Ages 18 to 40 yearsHealthy volunteers can take part
Conditions the study is for: Microbial Colonization
What is being tested?: Omadacycline Injection
Type of treatment: Pill or oral medicine, Injection or infusion
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 8 participants
Where: 1 siteUnited States
Study dates: 20 Mar 2023to 11 Jul 2023
Phase: Phase 4
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 40 years
All sexes
Healthy volunteers accepted
Adult

Who may be able to join

18-40 years of age
Willing and able to comply with all study procedures
Considered healthy without history of cardiovascular, gastrointestinal, hepatic, or renal disease
males or females - females of child bearing potential must agree to use a highly effective contraception during the study and for at least 7 days after the last dose of omadacycline

Who cannot join

Consumed probiotics within 30 days before enrollment
Consumed antibiotics within 90 days prior to enrollment
Known hypersensitivity to omadacycline or tetracycline-class antibiotics
pregnant or breastfeeding
in the opinion of the investigator is experiencing signs or symptoms of acute illness that increase the risk of adverse effects from participating in the study
previously participated in the study

Trial locations and contacts

1 site in 1 country.

United States1 site

Wake Forest Baptist Health
Winston-Salem, North Carolina, 27157

Other trials in United States

About this study

Official title: Effects of IV Omadacycline on Gut Microbiome

Read the detailed description

The plan to enroll eight healthy volunteers between the ages of 18 and 40 years and without history of cardiovascular, gastrointestinal, hepatic, or renal disease to receive 5 days of intravenous omadacycline followed by 5 days of oral omadacycline. Stool and saliva samples will be collected at pre-specified times and analyzed to characterize the impact of IV omadacycline on gut microbiome.

Conditions: Microbial Colonization
Being tested: Omadacycline Injection
Keywords: Gut Microbiome, Clostridioides difficile
Medical subject headings: Communicable Diseases

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Omadacycline InjectionDrug
Also called Omadacycline oral
All participants will receive Intravenous (IV) omadacycline

Study groups in NCT05515562
Study group	Role	What they receive
Intravenous (IV) Omadacycline	Experimental	All participants will receive 5 days of IV omadacycline followed by 5 days of oral omadacycline Receives: Drug: Omadacycline Injection

What is being measured

The primary outcome is the main question the study is designed to answer.

Phylum Level Mean Proportional Relative Abundance
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Measured: Day 30
Phylum Level Mean Proportional Relative Abundance
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Measured: Baseline
Phylum Level Mean Proportional Relative Abundance
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Measured: Day 5
Phylum Level Mean Proportional Relative Abundance
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Measured: Day 10
Bacterial DNA Per Gram of Stool
nanograms (ng) per gram of stool for bacterial DNA
Measured: Baseline
Bacterial DNA Per Gram of Stool
nanograms (ng) per gram of stool for bacterial DNA
Measured: During Therapy up to Day 6
Bacterial DNA Per Gram of Stool
nanograms (ng) per gram of stool for bacterial DNA
Measured: End of Therapy up to Day 10
Order Level Mean Proportional Relative Abundance
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Measured: Baseline
Order Level Mean Proportional Relative Abundance
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Measured: Day 5
Order Level Mean Proportional Relative Abundance
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Measured: Day 10
Order Level Mean Proportional Relative Abundance
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Measured: Day 30

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

20 Mar 202311 Jul 2023

First posted25 Aug 2022
Study start20 Mar 2023
Primary completion11 Jul 2023
Study completion11 Jul 2023

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Other trials for Microbial ColonizationStudies of the same condition, open and under way.
More trials run by Wake Forest University Health SciencesThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 4
Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrolment: 8 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT05515562
Sponsor's protocol ID: IRB00081259
Status last verified: Feb 2024
First submitted: 23 Aug 2022
Last updated: 17 Mar 2025
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: Yes: IPD that underlie the results reported in this article, after deidentification

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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All Microbial Colonization trials

Study at a glance

From the registry record, last updated by the sponsor on 17 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Effects of IV Omadacycline on Gut Microbiome
ClinicalTrials.gov ID: NCT05515562
Acronym / sponsor ID: IRB00081259
Conditions: Microbial Colonization
Keywords: Gut Microbiome, Clostridioides difficile
Phase: Phase 4
Study type: Interventional
Recruitment status: Completed
Enrolment: 8 participants (actual)
Lead sponsor: Wake Forest University Health SciencesUniversity, hospital or other
Collaborators: University of Houston, High Point University, Paratek Pharmaceuticals Inc
Study start: 20 Mar 2023 (actual)
Primary completion: 11 Jul 2023 (actual)
Study completion: 11 Jul 2023 (actual)
First posted: 25 Aug 2022 (actual)
Results: Posted 17 Mar 2025

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Number of arms: 1

Arm	Type	Receives
Intravenous (IV) Omadacycline	Experimental	Drug: Omadacycline InjectionAll participants will receive 5 days of IV omadacycline followed by 5 days of oral omadacycline

Who may qualify

Ages: 18 to 40 years
Sex: All
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (4 listed)

18-40 years of age
Willing and able to comply with all study procedures
Considered healthy without history of cardiovascular, gastrointestinal, hepatic, or renal disease
males or females - females of child bearing potential must agree to use a highly effective contraception during the study and for at least 7 days after the last dose of omadacycline

Key exclusion criteria (6 listed)

Consumed probiotics within 30 days before enrollment
Consumed antibiotics within 90 days prior to enrollment
Known hypersensitivity to omadacycline or tetracycline-class antibiotics
pregnant or breastfeeding
in the opinion of the investigator is experiencing signs or symptoms of acute illness that increase the risk of adverse effects from participating in the study

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Omadacycline InjectionAlso: Omadacycline oralAll participants will receive Intravenous (IV) omadacycline	Drug	Intravenous (IV) Omadacycline

Primary outcome

Phylum Level Mean Proportional Relative Abundance
Time frame: Day 30
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Phylum Level Mean Proportional Relative Abundance
Time frame: Baseline
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Phylum Level Mean Proportional Relative Abundance
Time frame: Day 5
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Phylum Level Mean Proportional Relative Abundance
Time frame: Day 10
In general, the healthy volunteer analyses will assess changes in total and species-specific microbiota over time as well as changes in microbial diversity.
Bacterial DNA Per Gram of Stool
Time frame: Baseline
nanograms (ng) per gram of stool for bacterial DNA
Bacterial DNA Per Gram of Stool
Time frame: During Therapy up to Day 6
nanograms (ng) per gram of stool for bacterial DNA
Bacterial DNA Per Gram of Stool
Time frame: End of Therapy up to Day 10
nanograms (ng) per gram of stool for bacterial DNA
Order Level Mean Proportional Relative Abundance
Time frame: Baseline
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Order Level Mean Proportional Relative Abundance
Time frame: Day 5
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Order Level Mean Proportional Relative Abundance
Time frame: Day 10
Order Level Mean Proportional Relative Abundance - Relative abundance % for order
Order Level Mean Proportional Relative Abundance
Time frame: Day 30
Order Level Mean Proportional Relative Abundance - Relative abundance % for order

Results and safety

Results posted to the registry on 17 Mar 2025, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Intravenous (IV) Omadacycline	8	8

Primary outcome: Phylum Level Mean Proportional Relative Abundance

Time frame: Day 30. Mean (Standard Deviation). Unit: % gram positive (+) for phylum

Measure	Intravenous (IV) Omadacycline n = 8
Actinobacteriota	0.167 (0.0622)
Bacteroidota	0.0271 (0.0314)
Bacillota	0.686 (0.114)
Euryarchaeota	0.0391 (0.103)
Verrucomicrobiota	0.0371 (0.0750)
Proteobacteria	0.0399 (0.0610)
Other Phyla <2%	0.00324 (0.00809)

Primary outcome: Phylum Level Mean Proportional Relative Abundance

Time frame: Baseline. Mean (Standard Deviation). Unit: % gram positive (+) for phylum

Measure	Intravenous (IV) Omadacycline n = 8
Actinobacteriota	0.130 (0.0390)
Bacteroidota	0.0135 (0.0152)
Bacillota	0.779 (0.0879)
Euryarchaeota	0.0388 (0.0933)
Verrucomicrobiota	0.0173 (0.0227)
Proteobacteria	0.0205 (0.0342)
Other Phyla <2%	0.00110 (0.00190)

Primary outcome: Phylum Level Mean Proportional Relative Abundance

Time frame: Day 5. Mean (Standard Deviation). Unit: % gram positive (+) for phylum

Measure	Intravenous (IV) Omadacycline n = 8
Actinobacteriota	0.225 (0.0469)
Bacteroidota	0.0507 (0.0812)
Bacillota	0.432 (0.0814)
Euryarchaeota	0 (0.0001)
Verrucomicrobiota	0.131 (0.106)
Proteobacteria	0.158 (0.141)
Other Phyla <2%	0.00310 (0.00407)

Primary outcome: Phylum Level Mean Proportional Relative Abundance

Time frame: Day 10. Mean (Standard Deviation). Unit: % gram positive (+) for phylum

Measure	Intravenous (IV) Omadacycline n = 8
Actinobacteriota	0.198 (0.101)
Bacteroidota	0.0459 (0.0848)
Bacillota	0.246 (0.191)
Euryarchaeota	0.152 (0.262)
Verrucomicrobiota	0.210 (0.203)
Proteobacteria	0.147 (0.112)
Other Phyla <2%	0.00105 (0.00144)

Adverse events

Time frame: 31 days. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Intravenous (IV) Omadacycline	0 of 8 (0%)	7 of 8 (87.5%)	0 of 8

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 17 Mar 2025.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Individual participant dataSharing planned: Yes. IPD that underlie the results reported in this article, after deidentification

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

John C Williamson, PharmD principal investigator

Wake Forest University Health Sciences

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Omadacycline Injection in people with Microbial Colonization, run by Wake Forest University Health Sciences at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 17 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 17 Mar 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Phylum Level Mean Proportional Relative Abundance (time frame: Day 30). The study lists 11 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05515562.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Mar 2025.