Development and Validation of Gut Permeability SensorGutPermNCT03434639
Fluorescence Spectroscopy for Gut Permeability Assessment
An observational study of Development and Validation of Gut Permeability Sensor and Permeability; Increased, run by Imperial College London at 1 site in United Kingdom.
Trial summary
This research aims to develop portable devices - known as fluorescence spectrometers - to monitor the leakage of fluorescent dyes out of the gut into the blood stream. These devices will measure the leakiness (permeability) of the gut in a non-invasive manner and will provide an early warning that patients are at risk… Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Development and Validation of Gut Permeability Sensor, Permeability; Increased, Celiac Disease
- What is being tested?
- Spectroscopic gut permeability test
- Type of treatment
- Pill or oral medicine, Injection or infusion
- How many people
- 50 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 29 Mar 2019to 30 Sep 2021
- Phase
- Observational
- Are there results?
- None posted in the registry
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 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Potential participants will be identified and approached by members of their healthcare/clinical team. They will be identified based on their clinical condition and its potential relevance to the study - i.e. ophthalmology patients due to receive intravenous doses of fluorescein or ICG for Stage 1; GI and non-GI patients exhibiting increased intestinal permeability for Stages 2 and 3. Healthy volunteers with no indication of increased intestinal permeability will be recruited from Imperial College and St. Mary's Hospital staff. Potential healthy volunteers will be approached in person by members of the research team.
Who may be able to join
- Ability to give informed consent
- Aged 18 years or above
- No evidence of prior adverse reactions to fluorescein, ICG, dextran or PEG
- No evidence of prior adverse reactions to iodine (for ICG experiments only)
- For healthy volunteers: healthy with no active GI/liver disease (or other condition in which increased gut permeability is expected, e.g. HIV) and no antibiotics taken within the previous four weeks.
- For cases: exhibiting symptoms of GI, liver or other diseases (e.g. HIV) in which increased intestinal permeability is expected.
- For ophthalmology patients recruited in Stage 1: healthy (i.e. as described above for healthy volunteers) and prescribed to have an ophthalmic angiography with an intravenous injection of either fluorescein or ICG.
Who cannot join
- Unable to give informed consent
- Aged <18 years
- Previous adverse reaction to fluorescein, ICG, dextran or PEG
- Known allergy to iodine (for ICG experiments only)
- Pregnancy (in Stage 1 this will be at the discretion of the patient's ophthalmologist)
- Breastfeeding (in Stage 1 this will be at the discretion of the ophthalmologist)
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site, 1 recruiting
- Recruiting
IMPERIAL COLLEGE Healthcare Trust
London, W2 1NY
Alexander J Thompson, PhD, alex.thompson08@imperial.ac.uk
Alexander J Thompson, PhD
About this study
Official title: Non-invasive Transcutaneous Spectroscopy for the Assessment of Gut Permeability
This research aims to develop portable devices - known as fluorescence spectrometers - to monitor the leakage of fluorescent dyes out of the gut into the blood stream. These devices will measure the leakiness (permeability) of the gut in a non-invasive manner and will provide an early warning that patients are at risk of infections caused by the unwanted flow of bacteria from the intestine to the rest of the body.
Read the detailed description
"Leaky gut" - or, increased permeability of the intestine - involves the leakage of certain intestinal constituents (e.g. endotoxins or even bacteria) from the gut into the rest of the body. This condition is associated with many widespread diseases including coeliac disease, inflammatory bowel disease, HIV, liver cirrhosis, sepsis and environmental enteric dysfunction (EED). It has a considerable impact on quality of life and, in extreme cases (e.g. sepsis), it can even lead to death. Furthermore, in the developing world (as part of EED), it severely hampers the mental and physical development of young children. Thus, new devices that can help us to learn more about leaky gut and more accurately monitor its effects are urgently needed.
In this project, patients will drink a small dose of a fluorescent dye. Then, by shining light on the patients' skin and recording the color and brightness of the light (fluorescence) that comes back, it will be possible to measure the amount of dye that has leaked into the blood (indicating the likelihood that bacteria are escaping from the gut and causing infections). We refer to this as a "Spectroscopic gut permeability test." We will also ask patients to take a traditional permeability test (known as a PEG permeability test) so that we can validate our new sensor. Overall, this research will deliver vital information that will improve our understanding of leaky gut and help guide the development of treatments for the many diseases in which it occurs.
- Conditions
- Development and Validation of Gut Permeability Sensor, Permeability; Increased, Celiac Disease, Inflammatory Bowel Diseases, Liver Diseases, HIV/AIDS
- Being tested
- Spectroscopic gut permeability test
- Keywords
- Gut permeability, Fluorescence, Spectroscopy, Wearable sensor, Leaky gut
- Medical subject headings
- Celiac Disease, Inflammatory Bowel Diseases, Liver Diseases, Acquired Immunodeficiency Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Spectroscopic gut permeability testDiagnostic test
The spectroscopic gut permeability test first involves patients receiving an oral dose of one or more fluorescent dyes. A wearable sensor will then be attached to the patients' skin and this will be used to monitor the leakage of the fluorescent dyes from the intestine into the blood stream in a non-invasive manner. In this way, a measure of the permeability of the intestine will be obtained.
Note that patients in Group 1 (ophthalmology patients) will not receive oral doses of contrast agents. Instead, the wearable sensor will simply be used to detect the presence of fluorescent dyes that were administered intravenously as part of planned ophthalmic procedures.
Complete details of the spectroscopic gut permeability test can be found in the attached protocol.
| Study group | Role | What they receive |
|---|---|---|
| 1 - Ophthalmology patients | Ophthalmology patients who are receiving an intravenous dose of either fluorescein or indocyanine green (ICG) as part of their routine ophthalmic care (e.g. as part of a fluorescence angiography examination) will be recruited to the first stage of this study. These patients will take part in preliminary studies aimed at determining whether it is possible to detect fluorescein and ICG in the blood using transcutaneous fluorescence measurements. Receives: Diagnostic Test: Spectroscopic gut permeability test | |
| 2a - Healthy subjects | Healthy subjects with no known issues of increased gut permeability. These subjects will act as negative controls in all gut permeability studies. Receives: Diagnostic Test: Spectroscopic gut permeability test | |
| 2b - Healthy subjects (gastric emptying) | A subset of healthy volunteers will be recruited to take part in experiments to help in understanding the impact of gastric emptying rate as a confounding factor in measurements of gut permeability. Receives: Diagnostic Test: Spectroscopic gut permeability test | |
| 3 - Increased permeability | Gastro-intestinal (GI) and non-GI patients who are expected to exhibit increased gut permeability (e.g. patients with celiac disease, inflammatory bowel disease (IBD), liver disease, HIV or another condition in which increased intestinal permeability is common). The more extreme cases in this group will act as positive controls. Receives: Diagnostic Test: Spectroscopic gut permeability test |
What is being measured
The primary outcome is the main question the study is designed to answer.
Blood concentration from intravenous injection
Where the blood concentration of fluorescent dye is known - for example, in ophthalmology patients who have received a direct intravenous dose of contrast agent - a direct comparison will be made between these values and the results of the spectroscopic gut permeability test without the need for further measurements.
Measured: 1 day (study visit)
Blood concentration from samples
In subjects receiving an oral dose of contrast agent, blood samples will be taken alongside the spectroscopic measurements in order to permit accurate ex vivo quantification of the serum concentration in the laboratory. These values will be compared with the spectroscopic findings.
Measured: 1 day (study visit)
PEG permeability assay
In patients who are also undergoing polyethylene glycol (PEG)-based permeability assays, spectroscopic permeability measurements will be compared to the results of this more traditional approach.
Measured: 1 week (after study visit)
Histology
Finally, in patients for whom intestinal biopsy and histology data is available, spectroscopic permeability measurements will be compared against histological measures of epithelial damage and permeability.
Measured: 1 day (study visit)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Feb 2018
- Study start29 Mar 2019
- Primary completion30 Sep 2021 (estimated)
- Study completion30 Sep 2021 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Development and Validation of Gut Permeability SensorStudies of the same condition, open and under way.
- More trials run by Imperial College LondonThe 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
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Imperial College London
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Alexander Thompson, Imperial College London
- Investigators
- Alex J Thompson, PhD, Principal investigator, Imperial College London
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03434639
- Sponsor's protocol ID
- 18SM4374
- Acronym
- GutPerm
- Status last verified
- Feb 2020
- First submitted
- 9 Feb 2018
- Last updated
- 12 Feb 2020
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Anonymized participant data will be made available to other researchers once the final results of the study have been published.
Publications
Gan J, Chen Q, Monfort Sanchez E, Mandal N, Xu J, Wang Z, Agarwal A, Oluwatunmise E, Ramkumar P, Salam A, Chekmeneva E, Gomez-Romero M, Maslen L, Balarajah S, Perry R, Yong KK, Hoare J, Powell N, Alexander J, Avery J, Ashrafian H, Darzi A, Thompson AJ. Non-invasive fluorescence sensing reveals changes in intestinal barrier function and gastric emptying rate in a first-in-human study of Crohn's disease. Ther Adv Gastroenterol. 2025 Aug 13;18:17562848251361634. doi: 10.1177/17562848251361634. eCollection 2025.
PubMed 40821739
Study at a glance
From the registry record, last updated by the sponsor on 12 Feb 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Non-invasive Transcutaneous Spectroscopy for the Assessment of Gut Permeability
- ClinicalTrials.gov ID
- NCT03434639
- Acronym / sponsor ID
- GutPerm / 18SM4374
- Conditions
- Development and Validation of Gut Permeability Sensor, Permeability; Increased, Celiac Disease, Inflammatory Bowel Diseases, Liver Diseases, HIV/AIDS
- Keywords
- Gut permeability, Fluorescence, Spectroscopy, Wearable sensor, Leaky gut
- Study type
- Observational
- Recruitment status
- Unknown status
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Imperial College LondonUniversity, hospital or other
- Study start
- 29 Mar 2019 (actual)
- Primary completion
- 30 Sep 2021 (estimated)
- Study completion
- 30 Sep 2021 (estimated)
- First posted
- 15 Feb 2018 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This research aims to develop portable devices - known as fluorescence spectrometers - to monitor the leakage of fluorescent dyes out of the gut into the blood stream. These devices will measure the leakiness (permeability) of the gut in a non-invasive manner and will provide an early warning that patients are at risk of infections caused by the unwanted flow of bacteria from the intestine to the rest of the body.
Detailed description
"Leaky gut" - or, increased permeability of the intestine - involves the leakage of certain intestinal constituents (e.g. endotoxins or even bacteria) from the gut into the rest of the body. This condition is associated with many widespread diseases including coeliac disease, inflammatory bowel disease, HIV, liver cirrhosis, sepsis and environmental enteric dysfunction (EED). It has a considerable impact on quality of life and, in extreme cases (e.g. sepsis), it can even lead to death. Furthermore, in the developing world (as part of EED), it severely hampers the mental and physical development of young children. Thus, new devices that can help us to learn more about leaky gut and more accurately monitor its effects are urgently needed.
In this project, patients will drink a small dose of a fluorescent dye. Then, by shining light on the patients' skin and recording the color and brightness of the light (fluorescence) that comes back, it will be possible to measure the amount of dye that has leaked into the blood (indicating the likelihood that bacteria are escaping from the gut and causing infections). We refer to this as a "Spectroscopic gut permeability test." We will also ask patients to take a traditional permeability test (known as a PEG permeability test) so that we can validate our new sensor. Overall, this research will deliver vital information that will improve our understanding of leaky gut and help guide the development of treatments for the many diseases in which it occurs.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| 1 - Ophthalmology patients | – | Diagnostic Test: Spectroscopic gut permeability testOphthalmology patients who are receiving an intravenous dose of either fluorescein or indocyanine green (ICG) as part of their routine ophthalmic care (e.g. as part of a fluorescence angiography examination) will be recruited to the first stage of this study. These patients will take part in preliminary studies aimed at determining whether it is possible to detect fluorescein and ICG in the blood using transcutaneous fluorescence measurements. |
| 2a - Healthy subjects | – | Diagnostic Test: Spectroscopic gut permeability testHealthy subjects with no known issues of increased gut permeability. These subjects will act as negative controls in all gut permeability studies. |
| 2b - Healthy subjects (gastric emptying) | – | Diagnostic Test: Spectroscopic gut permeability testA subset of healthy volunteers will be recruited to take part in experiments to help in understanding the impact of gastric emptying rate as a confounding factor in measurements of gut permeability. |
| 3 - Increased permeability | – | Diagnostic Test: Spectroscopic gut permeability testGastro-intestinal (GI) and non-GI patients who are expected to exhibit increased gut permeability (e.g. patients with celiac disease, inflammatory bowel disease (IBD), liver disease, HIV or another condition in which increased intestinal permeability is common). The more extreme cases in this group will act as positive controls. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Potential participants will be identified and approached by members of their healthcare/clinical team. They will be identified based on their clinical condition and its potential relevance to the study - i.e. ophthalmology patients due to receive intravenous doses of fluorescein or ICG for Stage 1; GI and non-GI patients exhibiting increased intestinal permeability for Stages 2 and 3. Healthy volunteers with no indication of increased intestinal permeability will be recruited from Imperial College and St. Mary's Hospital staff. Potential healthy volunteers will be approached in person by members of the research team.
Key inclusion criteria (7 listed)
- Ability to give informed consent
- Aged 18 years or above
- No evidence of prior adverse reactions to fluorescein, ICG, dextran or PEG
- No evidence of prior adverse reactions to iodine (for ICG experiments only)
- For healthy volunteers: healthy with no active GI/liver disease (or other condition in which increased gut permeability is expected, e.g. HIV) and no antibiotics taken within the previous four weeks.
Key exclusion criteria (6 listed)
- Unable to give informed consent
- Aged <18 years
- Previous adverse reaction to fluorescein, ICG, dextran or PEG
- Known allergy to iodine (for ICG experiments only)
- Pregnancy (in Stage 1 this will be at the discretion of the patient's ophthalmologist)
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 |
|---|---|---|
| Spectroscopic gut permeability testThe spectroscopic gut permeability test first involves patients receiving an oral dose of one or more fluorescent dyes. A wearable sensor will then be attached to the patients' skin and this will be used to monitor the leakage of the fluorescent dyes from the intestine into the blood stream in a non-invasive manner. In this way, a measure of the permeability of the intestine will be obtained. Note that patients in Group 1 (ophthalmology patients) will not receive oral doses of contrast agents. Instead, the wearable sensor will simply be used to detect the presence of fluorescent dyes that were administered intravenously as part of planned ophthalmic procedures. Complete details of the spectroscopic gut permeability test can be found in the attached protocol. | Diagnostic test | 1 - Ophthalmology patients, 2a - Healthy subjects, 2b - Healthy subjects (gastric emptying), 3 - Increased permeability |
Primary outcome
Blood concentration from intravenous injection
Time frame: 1 day (study visit)
Where the blood concentration of fluorescent dye is known - for example, in ophthalmology patients who have received a direct intravenous dose of contrast agent - a direct comparison will be made between these values and the results of the spectroscopic gut permeability test without the need for further measurements.
Blood concentration from samples
Time frame: 1 day (study visit)
In subjects receiving an oral dose of contrast agent, blood samples will be taken alongside the spectroscopic measurements in order to permit accurate ex vivo quantification of the serum concentration in the laboratory. These values will be compared with the spectroscopic findings.
PEG permeability assay
Time frame: 1 week (after study visit)
In patients who are also undergoing polyethylene glycol (PEG)-based permeability assays, spectroscopic permeability measurements will be compared to the results of this more traditional approach.
Histology
Time frame: 1 day (study visit)
Finally, in patients for whom intestinal biopsy and histology data is available, spectroscopic permeability measurements will be compared against histological measures of epithelial damage and permeability.
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 12 Feb 2020.
- Derived from this study: PubMed 40821739Gan J, Chen Q, Monfort Sanchez E, Mandal N, Xu J, Wang Z, Agarwal A, Oluwatunmise E, Ramkumar P, Salam A, Chekmeneva E, Gomez-Romero M, Maslen L, Balarajah S, Perry R, Yong KK, Hoare J, Powell N, Alexander J, Avery J, Ashrafian H, Darzi A, Thompson AJ. Non-invasive fluorescence sensing reveals changes in intestinal barrier function and gastric emptying rate in a first-in-human study of Crohn's disease. Ther Adv Gastroenterol. 2025 Aug 13;18:17562848251361634. doi: 10.1177/17562848251361634. eCollection 2025.
- Individual participant dataSharing planned: Yes. Anonymized participant data will be made available to other researchers once the final results of the study have been published.
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.
Alex J Thompson, PhD principal investigator
Imperial College London
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Development and Validation of Gut Permeability Sensor and Permeability; Increased, run by Imperial College London at 1 site in United Kingdom.
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 7 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: status not confirmed, as of the sponsor's last update on 12 Feb 2020. 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 Kingdom. 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.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Alex J Thompson, PhD (+442033125035, alex.thompson08@imperial.ac.uk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Blood concentration from intravenous injection (time frame: 1 day (study visit)). The study lists 4 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 NCT03434639, which also lists 1 linked publication.
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 12 Feb 2020.