Lymphopenia Due to COVID-19TangeloNCT04874818
CD8+ T-cell PET/CT Imaging in COVID-19 Patients
An observational study of Lymphopenia Due to COVID-19 and T-cell, run by Radboud University Medical Center at 1 site in Netherlands.
Trial summary
A subset of patients diagnosed with severe acute respiratory syndrome (SARS)-CoV2 infection present with lymphopenia. The degree of lymphopenia, and in particular reduced cluster of differentiation (CD)8+ T-cell numbers, is correlated with clinical deterioration and intensive care unit (ICU) admission. Read more about this study
- Who is it for?
- Ages 50 years and older
- Conditions the study is for
- Lymphopenia Due to COVID-19, T-cell, PET Imaging
- What is being tested?
- [89Zr]Df-IAB22M2C PET/CT scan
- How many people
- 5 participants
- Where
- 1 siteNetherlands
- Study dates
- 14 Feb 2022to 31 Dec 2022
- 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 50 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: The study population for this pilot study exists of 20 evaluable patients with a proven SARS-CoV2 infection admitted to the Infectious Diseases ward. Patients presenting in the Radboud University Medical Center will be considered for recruitment.
Who may be able to join
- a microbiologically proven SARS-CoV2 infection
- More than 50 years of age;
- Ability to provide written informed consent.
Who cannot join
- Contra-indication for PET: Pregnancy, Breast-feeding, Severe claustrophobia.
- Contra-indication for administration of iodine-containing contrast agents
- Other serious illness, e.g. history of malignancies or auto-immune disorders
- Known pre-existing lymphopenia from an unrelated other medical condition
- Estimated creatinine clearance ≤ 30 mL/min according to the Cockcroft-Gault formula (or local institutional standard method) OR oligo-uric patients (<400 mL/24hr)
Trial locations and contacts
1 site in 1 country.
Netherlands1 site
Radboud university medical center
Nijmegen, Gelderland, 6500HB
About this study
Official title: [89Zr]Df-IAB22M2C Anti-CD8 Minibody PET/CT Imaging to Assess the in Vivo Distribution of CD8+ T-cells in COVID-19 Patients
A subset of patients diagnosed with severe acute respiratory syndrome (SARS)-CoV2 infection present with lymphopenia. The degree of lymphopenia, and in particular reduced cluster of differentiation (CD)8+ T-cell numbers, is correlated with clinical deterioration and intensive care unit (ICU) admission. The underlying reasons for lymphopenia in coronavirus disease (COVID)-19 is currently unclear, We aim to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV2 presenting with lymphopenia or with normal lymphocyte counts, using Zirconium-89 ([89Zr])Df-IAB22M2C positron emission tomography (PET) imaging.
Read the detailed description
Rationale: A subset of patients diagnosed with SARS-CoV2 infection present with lymphopenia. The degree of lymphopenia, and in particular reduced CD8+ T-cell numbers, is strongly correlated with clinical deterioration and ICU admission .
The underlying reasons for lymphopenia in COVID-19 is currently unclear, but several hypotheses have been put forward; 1) sequestration of CD8+ T-cells in peripheral tissues (e.g. lung) either during the effector phase of their lifespan or passively by local chemotactic signals, 2) accelerated maturation and apoptosis either induced by storm of inflammatory cytokines or direct infection or 3) resulting from decreased lymphopoiesis induced by reduced levels of stem cell factor. The lack of data on in vivo distribution of CD8+ T-cells hampers a more thorough understanding of this critical prognostic factor.
Aim: We aim to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV2 presenting with lymphopenia or with normal lymphocyte counts, using [89Zr]Df-IAB22M2C PET/CT imaging.
Study design: This is a prospective, observational non-randomized pilot study in 20 patients with microbiologically proven SARS-CoV2 infection. All patients will undergo a whole body [89Zr]Df-IAB22M2C PET/CT scan.
Study population: Twenty patients ≥50 years of age with proven COVID-19, who are admitted to the ward will be included, patients will be stratified according to lymphocyte counts on admission to ensure an even distribution: presenting with lymphopenia (<1.0 x10e9/L) (n=10) and with lymphocyte numbers within normal range (1.0 - 3.5 x10e9/L) (n=10).
Study procedure: All patients will undergo a [89Zr]Df-IAB22M2C PET/CT scan 21-27 hours post intravenous injection of 1.5mg protein dose labelled with 37 megabecquerel (MBq) (1 mCi) 89Zr; and one additional blood sample at the day of scanning.
Primary study objective: The primary objective of this study is to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV-2 presenting with lymphopenia or with normal lymphocyte counts, using [89Zr]Df-IAB22M2C PET/CT imaging.
Secondary study objectives:
- To assess the spatial correlation between [89Zr]Df-IAB22M2C uptake and abnormal findings on routine contrast-enhanced CT scan of the chest
- To assess the correlation between in vivo biodistribution of [89Zr]Df-IAB22M2C and concurrent flowcytometric phenotypic and quantitative assessment of lymphocyte populations
- To explore the correlation between in vivo biodistribution of [89Zr]Df-IAB22M2C and clinical course of disease
- Conditions
- Lymphopenia Due to COVID-19, T-cell, PET Imaging
- Being tested
- [89Zr]Df-IAB22M2C PET/CT scan
- Keywords
- COVID-19, lymphopenia, T-cells, PET imaging
- Medical subject headings
- COVID-19, Lymphopenia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
[89Zr]Df-IAB22M2C PET/CT scanDiagnostic test
PET imaging procedure
| Study group | Role | What they receive |
|---|---|---|
| lymphopenia | lymphocyte counts (<1.0 x10e9/L) Receives: Diagnostic Test: [89Zr]Df-IAB22M2C PET/CT scan | |
| normal lymphocyte numbers | lymphocyte counts ((1.0 - 3.5 x10e9/L)) Receives: Diagnostic Test: [89Zr]Df-IAB22M2C PET/CT scan |
What is being measured
The primary outcome is the main question the study is designed to answer.
The primary objective of this study is to quantify uptake of [89Zr]Df-IAB22M2C, as a surrogate for the presence of CD8+ T-cells, in major organ systems of patients with proven SARS-CoV-2 presenting with lymphopenia or with normal lymphocyte counts.
The main study parameter is the SUVmean uptake of [89Zr]Df-IAB22M2C in major organs systems, e.g. lungs, spleen, bone marrow, liver and bloodpool
Measured: 18 months
Secondary outcomes (3)
Based on imaging
- Spatial correlation of SUVmean per lung segment with CORADS score per lung segment
Measured: 18 months
Based on laboratory parameters
- In vivo biodistribution of [89Zr]Df-IAB22M2C will be correlated to laboratory test 3) In vivo biodistribution of [89Zr]Df-IAB22M2C will be correlated with lymphocyte counts (x10e9/L)
Measured: 18 months
Based on clinical characteristics
- In vivo biodistribution of [89Zr]Df-IAB22M2C will be correlated with duration of hospital stay (days)
Measured: 18 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 May 2021
- Study start14 Feb 2022
- Primary completion31 Dec 2022
- Study completion31 Dec 2022
Why it stopped: COVID-19 pandemic resided
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Lymphopenia Due to COVID-19Studies of the same condition, open and under way.
- More trials run by Radboud University Medical CenterThe 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
- 5 participants (actual)
Sponsor and investigators
- Lead sponsor
- Radboud University Medical Center
- Sponsor type
- University, hospital or other
- Collaborators
- ImaginAb, Inc.
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04874818
- Sponsor's protocol ID
- NL76248.091.20
- Other IDs
- 2020-005984-29
- Acronym
- Tangelo
- Status last verified
- Jun 2024
- First submitted
- 28 Apr 2021
- Last updated
- 2 Apr 2025
- Results posted
- No
- Data monitoring committee
- Yes
- 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 2 Apr 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- [89Zr]Df-IAB22M2C Anti-CD8 Minibody PET/CT Imaging to Assess the in Vivo Distribution of CD8+ T-cells in COVID-19 Patients
- ClinicalTrials.gov ID
- NCT04874818
- Acronym / sponsor ID
- Tangelo / NL76248.091.20
- Conditions
- Lymphopenia Due to COVID-19, T-cell, PET Imaging
- Keywords
- COVID-19, lymphopenia, T-cells, PET imaging
- Study type
- Observational
- Recruitment status
- TerminatedReason stopped: COVID-19 pandemic resided
- Enrolment
- 5 participants (actual)
- Lead sponsor
- Radboud University Medical CenterUniversity, hospital or other
- Collaborators
- ImaginAb, Inc.
- Study start
- 14 Feb 2022 (actual)
- Primary completion
- 31 Dec 2022 (actual)
- Study completion
- 31 Dec 2022 (actual)
- First posted
- 6 May 2021 (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.
A subset of patients diagnosed with severe acute respiratory syndrome (SARS)-CoV2 infection present with lymphopenia. The degree of lymphopenia, and in particular reduced cluster of differentiation (CD)8+ T-cell numbers, is correlated with clinical deterioration and intensive care unit (ICU) admission. The underlying reasons for lymphopenia in coronavirus disease (COVID)-19 is currently unclear, We aim to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV2 presenting with lymphopenia or with normal lymphocyte counts, using Zirconium-89 ([89Zr])Df-IAB22M2C positron emission tomography (PET) imaging.
Detailed description
Rationale: A subset of patients diagnosed with SARS-CoV2 infection present with lymphopenia. The degree of lymphopenia, and in particular reduced CD8+ T-cell numbers, is strongly correlated with clinical deterioration and ICU admission .
The underlying reasons for lymphopenia in COVID-19 is currently unclear, but several hypotheses have been put forward; 1) sequestration of CD8+ T-cells in peripheral tissues (e.g. lung) either during the effector phase of their lifespan or passively by local chemotactic signals, 2) accelerated maturation and apoptosis either induced by storm of inflammatory cytokines or direct infection or 3) resulting from decreased lymphopoiesis induced by reduced levels of stem cell factor. The lack of data on in vivo distribution of CD8+ T-cells hampers a more thorough understanding of this critical prognostic factor.
Aim: We aim to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV2 presenting with lymphopenia or with normal lymphocyte counts, using [89Zr]Df-IAB22M2C PET/CT imaging.
Study design: This is a prospective, observational non-randomized pilot study in 20 patients with microbiologically proven SARS-CoV2 infection. All patients will undergo a whole body [89Zr]Df-IAB22M2C PET/CT scan.
Study population: Twenty patients ≥50 years of age with proven COVID-19, who are admitted to the ward will be included, patients will be stratified according to lymphocyte counts on admission to ensure an even distribution: presenting with lymphopenia (<1.0 x10e9/L) (n=10) and with lymphocyte numbers within normal range (1.0 - 3.5 x10e9/L) (n=10).
Study procedure: All patients will undergo a [89Zr]Df-IAB22M2C PET/CT scan 21-27 hours post intravenous injection of 1.5mg protein dose labelled with 37 megabecquerel (MBq) (1 mCi) 89Zr; and one additional blood sample at the day of scanning.
Primary study objective: The primary objective of this study is to assess differences in the in vivo distribution of CD8+ T-cells in patients with proven SARS-CoV-2 presenting with lymphopenia or with normal lymphocyte counts, using [89Zr]Df-IAB22M2C PET/CT imaging.
Secondary study objectives:
- To assess the spatial correlation between [89Zr]Df-IAB22M2C uptake and abnormal findings on routine contrast-enhanced CT scan of the chest
- To assess the correlation between in vivo biodistribution of [89Zr]Df-IAB22M2C and concurrent flowcytometric phenotypic and quantitative assessment of lymphocyte populations
- To explore the correlation between in vivo biodistribution of [89Zr]Df-IAB22M2C and clinical course of disease
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| lymphopenia | – | Diagnostic Test: [89Zr]Df-IAB22M2C PET/CT scanlymphocyte counts (<1.0 x10e9/L) |
| normal lymphocyte numbers | – | Diagnostic Test: [89Zr]Df-IAB22M2C PET/CT scanlymphocyte counts ((1.0 - 3.5 x10e9/L)) |
Who may qualify
- Ages
- 50 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study population for this pilot study exists of 20 evaluable patients with a proven SARS-CoV2 infection admitted to the Infectious Diseases ward. Patients presenting in the Radboud University Medical Center will be considered for recruitment.
Key inclusion criteria (3 listed)
- a microbiologically proven SARS-CoV2 infection
- More than 50 years of age;
- Ability to provide written informed consent.
Key exclusion criteria (5 listed)
- Contra-indication for PET: Pregnancy, Breast-feeding, Severe claustrophobia.
- Contra-indication for administration of iodine-containing contrast agents
- Other serious illness, e.g. history of malignancies or auto-immune disorders
- Known pre-existing lymphopenia from an unrelated other medical condition
- Estimated creatinine clearance ≤ 30 mL/min according to the Cockcroft-Gault formula (or local institutional standard method) OR oligo-uric patients (<400 mL/24hr)
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 |
|---|---|---|
| [89Zr]Df-IAB22M2C PET/CT scanPET imaging procedure | Diagnostic test | lymphopenia, normal lymphocyte numbers |
Primary outcome
The primary objective of this study is to quantify uptake of [89Zr]Df-IAB22M2C, as a surrogate for the presence of CD8+ T-cells, in major organ systems of patients with proven SARS-CoV-2 presenting with lymphopenia or with normal lymphocyte counts.
Time frame: 18 months
The main study parameter is the SUVmean uptake of [89Zr]Df-IAB22M2C in major organs systems, e.g. lungs, spleen, bone marrow, liver and bloodpool
3 secondary outcomes
Based on imaging
Time frame: 18 months
Based on laboratory parameters
Time frame: 18 months
Based on clinical characteristics
Time frame: 18 months
Results and safety
The study was stopped early (reason given: COVID-19 pandemic resided). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Apr 2025.
- Individual participant dataSharing planned: No
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.
The record lists no contact. Use the official record to reach the sponsor.
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 Lymphopenia Due to COVID-19 and T-cell, run by Radboud University Medical Center at 1 site in Netherlands.
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 3 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: stopped early, as of the sponsor's last update on 2 Apr 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 Netherlands. 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?
The study was stopped early (reason given: COVID-19 pandemic resided). Results are not available in the source record.
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?
The primary objective of this study is to quantify uptake of [89Zr]Df-IAB22M2C, as a surrogate for the presence of CD8+ T-cells, in major organ systems of patients with proven SARS-CoV-2 presenting with lymphopenia or with normal lymphocyte counts. (time frame: 18 months). 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 2 Apr 2025.