Kidney TransplantESTIMATORNCT06472947
Non-invasive Evaluation of Graft Condition in Adult Patients With Kidney Transplant Using Ultrasound Localization Microscopy and Multispectral Optoacoustic Tomography
An observational study of Kidney Transplant and Kidney Biopsy, run by University of Erlangen-Nürnberg Medical School at 1 site in Germany.
Trial summary
In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using Multispectral Optoacoustic Tomography and Ultrasound Localization Microscopy (ULM). ULM imaging can be performed in a 2-dimensional and a 3-dimensional way (2D and 3D ULM). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Kidney Transplant, Kidney Biopsy
- What is being tested?
- ULM and MSOT
- Type of treatment
- Medical device
- How many people
- 10 participants
- Where
- 1 siteGermany
- Study dates
- 18 Jun 2024to 18 Jan 2028
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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
- No healthy volunteers
- Adult, Older adult
Study population: 10 patients with kidney transplant and indication for kidney biopsy
Who may be able to join
- kidney transplant
- indication for biopsy set in clinical routine
- minimum 18 years of age
- written consent
Who cannot join
- allergy against contrast agents/ SonoVue
- tatoos in examined areas
- contraindication against SonoVue
- pregnant women
- breast feeding women
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Germany1 site, 1 recruiting
- Recruiting
Department of Pediatrics and Adolescent Medicine
Erlangen, Bavaria, 91054
Ferdinand Knieling, MD, 0913185 33118, ferdinand.knieling@uk-erlangen.de
Adrian Regensburger, MD, +49 9131 8533118, adrian.regensburger@uk-erlangen.de
About this study
In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using Multispectral Optoacoustic Tomography and Ultrasound Localization Microscopy (ULM). ULM imaging can be performed in a 2-dimensional and a 3-dimensional way (2D and 3D ULM). Therefore, "ULM" in the following texts and measures will refer to 2D and 3D ULM.
New, non-invasive markers that allow conclusions to be drawn about the condition of the transplant should reduce the need for invasive diagnostic procedures in the future.
Read the detailed description
In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using multispectral multispectral optoacoustic tomography and ultrasound localization microscopy. Associated with common diseases such as arterial hypertension, diabetes mellitus and cardiovascular diseases, chronic renal failure is now a leading cause of death worldwide.
Around 10% of adults in Germany, but children are also affected. The terminal stage of renal insufficiency is defined by a glomerular filtration rate (GFR) which is only 15% of the normal rate and the need for renal replacement therapy in the form of dialysis or transplantation.
Not only the higher quality of life, but also the mortality rate make kidney transplantation the procedure of choice whenever possible.
After successful kidney transplantation, regular monitoring and evaluation of the organ transplant is of great importance to detect a rejection reaction as early as possible.
Among other things, this is done during an extensive annual examination. Not infrequently, and especially in the case of abnormalities in the laboratory diagnosis of blood and urine, a kidney biopsy is also necessary in order to assess the condition of the transplant in the best possible way.
As an invasive diagnostic procedure, the biopsy necessitates a stay in hospital, may result in side effects such as postoperative bleeding and represents a risk and an additional bruden for the patient.
MSOT has already been used to measure renal clearance and the biodistribution of fluorescent substances within the kidney, but new biomarkers have also been established in muscle and intestinal diseases and correlated with clinical scores. ULM has made the visualization of glomeruli, the smallest functional unit of the kidney, in living rats and humans and visualization of cerebral microvasculature in the human brain possible. In this study, the renal function in transplant patients will be evaluated as part of the annual examination and results from histology (biopsy), laboratory and ultrasound diagnostics will be correlated with data from MSOT and 2D and 3D ULM imaging.
The investigators believe that MSOT can be used to gain important molecular insights into the condition of the transplant. With ULM the investigators want to analyze the microvascular architecture within glomerular renal corpuscles and identify changes in perfusion dynamics as morphological signs for transplant evaluation.
- Conditions
- Kidney Transplant, Kidney Biopsy
- Being tested
- ULM and MSOT
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ULM and MSOTDevice
transplanted kidney will be examined non-invasively with ULM and MSOT
| Study group | Role | What they receive |
|---|---|---|
| Patient with kidney transplant | Included are adult (> 18 years) patients with kidney transplant where the indication for a kidney biopsy has been set during clinical routine Receives: Device: ULM and MSOT |
What is being measured
The primary outcome is the main question the study is designed to answer.
Visualization of microvascular architecture in the transplant kidney
Using Ultrasound Localization Microscopy (ULM) for the non invasive visualization of microvasculature
Measured: Day1
Quantification of microvascular dynamics in the transplanted kidney
Using Ultrasound Localization Microscopy (ULM) for the non invasive quantification of microvascular dynamics
Measured: Day1
MSOT in human kidney transplant
Measuring MSOT signals (Signals for total/oxygenated/deoxygenated hemoglobin, lipid and collagen) in the human kidney transplant
Measured: Day1
Secondary outcomes (16)
ULM visuals and histology
ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with histological parameters (e.g. Banff classification)
Measured: Day1
ULM visuals and laboratory results
- ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with laboratory chemical parameters (e.g. renal function parameters, inflammation parameters, immunological parameters)
Measured: Day1
ULM visuals and standard sonography
- ULM: Correlation of the vascular architecture of the transplant kidney visualized by ULM (e.g. number of segmented glomeruli) with sonographic parameters (e.g. resistance index (RI), flow velocity)
Measured: Day1
ULM quantification and histology
ULM: Correlation of parameters of quantified microvascular perfusion dynamics in the transplant kidney with histological parameters (e.g. Banff classification)
Measured: Day1
ULM quantification and laboratory results
- ULM: Correlation of parameters of the quantified microvascular perfusion dynamics in the transplant kidney with laboratory chemical parameters (including renal function parameters, inflammation parameters)
Measured: Day1
MSOT: Hb and histology
MSOT: Correlation of the signal determined with MSOT for total/oxygenated/deoxygenated
Measured: Day1
MSOT: hb and laboratory results
- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin with laboratory chemical parameters
Measured: Day1
MSOT hb and sonography
- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin determined with MSOT with sonographic parameters
Measured: Day1
MSOT hb and histology
- MSOT: Correlation of the signal for total/oxygenated/deoxygenated hemoglobin with with histological parameters
Measured: Day1
MSOT Lipid and laboratory results
- MSOT: Correlation of the signal for lipid determined with MSOT with laboratory chemical parameters
Measured: Day1
MSOT Lipid and sonographic results
MSOT: Correlation of the signal for lipid determined with MSOT with sonographic parameters parameters
Measured: Day1
MSOT lipid and histology
MSOT: Correlation of the signal for lipid determined with MSOT with histological parameters
Measured: Day1
MSOT collagen and sonography
- MSOT: Correlation of the signal for collagen determined with MSOT with sonographic parameters
Measured: Day1
MSOT collagen and histology
MSOT: Correlation of the signal for collagen determined with MSOT with histological parameters
Measured: Day1
MSOT collagen and laboratory results
- MSOT: Correlation of the signal for collagen determined with MSOT with laboratory chemical parameters
Measured: Day1
ULM quantification and sonography
Correlation of parameters of the quantified microvascular perfusion dynamics in the transplant kidney with sonography in transplanted kidney
Measured: Day1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Jun 2024
- Study start18 Jun 2024
- Primary completion18 Jan 2028 (estimated)
- Study completion18 Jan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Kidney TransplantStudies of the same condition, open and under way.
- More trials run by University of Erlangen-Nürnberg Medical SchoolThe 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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 10 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Erlangen-Nürnberg Medical School
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ferdinand Knieling, University of Erlangen-Nürnberg Medical School
- Investigators
- Ferdinand Knieling, PD Dr. Dr., Principal investigator, FAU Erlangen-Nuremberg
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06472947
- Sponsor's protocol ID
- NTX_ULM_MSOT
- Acronym
- ESTIMATOR
- Status last verified
- Mar 2026
- First submitted
- 18 Jun 2024
- Last updated
- 4 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Non-invasive Evaluation of Graft Condition in Adult Patients With Kidney Transplant Using Ultrasound Localization Microscopy and Multispectral Optoacoustic Tomography
- ClinicalTrials.gov ID
- NCT06472947
- Acronym / sponsor ID
- ESTIMATOR / NTX_ULM_MSOT
- Conditions
- Kidney Transplant, Kidney Biopsy
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 10 participants (estimated)
- Lead sponsor
- University of Erlangen-Nürnberg Medical SchoolUniversity, hospital or other
- Study start
- 18 Jun 2024 (actual)
- Primary completion
- 18 Jan 2028 (estimated)
- Study completion
- 18 Jan 2028 (estimated)
- First posted
- 25 Jun 2024 (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.
In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using Multispectral Optoacoustic Tomography and Ultrasound Localization Microscopy (ULM). ULM imaging can be performed in a 2-dimensional and a 3-dimensional way (2D and 3D ULM). Therefore, "ULM" in the following texts and measures will refer to 2D and 3D ULM.
New, non-invasive markers that allow conclusions to be drawn about the condition of the transplant should reduce the need for invasive diagnostic procedures in the future.
Detailed description
In this study, the condition of the kidney transplant in adults is to be assessed non-invasively using multispectral multispectral optoacoustic tomography and ultrasound localization microscopy. Associated with common diseases such as arterial hypertension, diabetes mellitus and cardiovascular diseases, chronic renal failure is now a leading cause of death worldwide.
Around 10% of adults in Germany, but children are also affected. The terminal stage of renal insufficiency is defined by a glomerular filtration rate (GFR) which is only 15% of the normal rate and the need for renal replacement therapy in the form of dialysis or transplantation.
Not only the higher quality of life, but also the mortality rate make kidney transplantation the procedure of choice whenever possible.
After successful kidney transplantation, regular monitoring and evaluation of the organ transplant is of great importance to detect a rejection reaction as early as possible.
Among other things, this is done during an extensive annual examination. Not infrequently, and especially in the case of abnormalities in the laboratory diagnosis of blood and urine, a kidney biopsy is also necessary in order to assess the condition of the transplant in the best possible way.
As an invasive diagnostic procedure, the biopsy necessitates a stay in hospital, may result in side effects such as postoperative bleeding and represents a risk and an additional bruden for the patient.
MSOT has already been used to measure renal clearance and the biodistribution of fluorescent substances within the kidney, but new biomarkers have also been established in muscle and intestinal diseases and correlated with clinical scores. ULM has made the visualization of glomeruli, the smallest functional unit of the kidney, in living rats and humans and visualization of cerebral microvasculature in the human brain possible. In this study, the renal function in transplant patients will be evaluated as part of the annual examination and results from histology (biopsy), laboratory and ultrasound diagnostics will be correlated with data from MSOT and 2D and 3D ULM imaging.
The investigators believe that MSOT can be used to gain important molecular insights into the condition of the transplant. With ULM the investigators want to analyze the microvascular architecture within glomerular renal corpuscles and identify changes in perfusion dynamics as morphological signs for transplant evaluation.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Patient with kidney transplant | – | Device: ULM and MSOTIncluded are adult (> 18 years) patients with kidney transplant where the indication for a kidney biopsy has been set during clinical routine |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- 10 patients with kidney transplant and indication for kidney biopsy
Key inclusion criteria (4 listed)
- kidney transplant
- indication for biopsy set in clinical routine
- minimum 18 years of age
- written consent
Key exclusion criteria (5 listed)
- allergy against contrast agents/ SonoVue
- tatoos in examined areas
- contraindication against SonoVue
- pregnant women
- breast feeding women
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 |
|---|---|---|
| ULM and MSOTtransplanted kidney will be examined non-invasively with ULM and MSOT | Device | Patient with kidney transplant |
Primary outcome
Visualization of microvascular architecture in the transplant kidney
Time frame: Day1
Using Ultrasound Localization Microscopy (ULM) for the non invasive visualization of microvasculature
Quantification of microvascular dynamics in the transplanted kidney
Time frame: Day1
Using Ultrasound Localization Microscopy (ULM) for the non invasive quantification of microvascular dynamics
MSOT in human kidney transplant
Time frame: Day1
Measuring MSOT signals (Signals for total/oxygenated/deoxygenated hemoglobin, lipid and collagen) in the human kidney transplant
16 secondary outcomes
ULM visuals and histology
Time frame: Day1
ULM visuals and laboratory results
Time frame: Day1
ULM visuals and standard sonography
Time frame: Day1
ULM quantification and histology
Time frame: Day1
ULM quantification and laboratory results
Time frame: Day1
MSOT: Hb and histology
Time frame: Day1
MSOT: hb and laboratory results
Time frame: Day1
MSOT hb and sonography
Time frame: Day1
MSOT hb and histology
Time frame: Day1
MSOT Lipid and laboratory results
Time frame: Day1
MSOT Lipid and sonographic results
Time frame: Day1
MSOT lipid and histology
Time frame: Day1
MSOT collagen and sonography
Time frame: Day1
MSOT collagen and histology
Time frame: Day1
MSOT collagen and laboratory results
Time frame: Day1
ULM quantification and sonography
Time frame: Day1
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Mar 2026.
- Individual participant dataSharing planned: No
Related trials for Kidney Transplant
Enrolling by invitation
Online Exercise Program for Transplant Patients: A Pilot Study
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RecruitingPhase 2
A Study of Mezagitamab in Adults With Late Antibody-Mediated Rejection (AMR) After a Kidney Transplant
Antibody-Mediated Rejection (AMR)
Not yet recruiting
Hypothermic Kidney Machine Perfusion With Omnisol
End Stage Renal Disease (ESRD), Kidney Transplant
Not yet recruitingEarly Phase 1
Biomarker-Guided Mycophenolate Mofetil Elimination in Low-Risk Older Adult Kidney Transplant Recipients
Kidney Transplant Recipient
Recruiting
Non-Invasive Monitoring of Pediatric Kidney Transplant Recipients and Immunosuppression Personalization: an Open-labeled Multicenter Randomized Controlled Study
Pediatric Kidney Disease, Transplant;Failure,Kidney
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.
Ferdinand Knieling, PD Dr. Dr. principal investigator
FAU Erlangen-Nuremberg
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 Kidney Transplant and Kidney Biopsy, run by University of Erlangen-Nürnberg Medical School at 1 site in Germany.
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 5 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: looking for participants now, as of the sponsor's last update on 4 Mar 2026. 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 Germany. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ferdinand Hannah Knieling, PD Dr. Dr. (0049 9131 85 33118, ferdinand.knieling@uk-erlangen.de), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Visualization of microvascular architecture in the transplant kidney (time frame: Day1). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 4 Mar 2026.