TuberculosisNCT05526885
Tuberculosis Diagnostic Trial of CAD4TB Screening Alone Compared to CAD4TB Screening Combined With a CRP Triage Test, Both Followed by Confirmatory Xpert MTB/RIF Ultra in Communities of Lesotho and South Africa
A study testing CAD4TB, POC-CRP and Xpert MTB/RIF Ultra in people with Tuberculosis, run by Klaus Reither at 2 sites in 2 countries.
Trial summary
According to WHO, about 40% of the incident TB cases in 2020 are either under-reported or under-diagnosed causing on one hand major health risks and on the other hand catastrophic financial consequences. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Tuberculosis
- What is being tested?
- CAD4TB, POC-CRP and Xpert MTB/RIF Ultra
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20,000 participants
- Where
- 2 sitesin 2 countries
- Study dates
- 7 Sep 2022to 31 Dec 2024
- Phase
- Interventional
- 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
Who may be able to join
- Willing and able to provide signed written consent or witnessed oral consent in the case of illiteracy, prior to undertaking any study-related procedure
- Adults (≥18 years)
Who cannot join
- Any condition for which participation in the study, as judged by the investigator or a designated staff member, could compromise the well-being of the subject or prevent, limit or confound protocol specified assessments
- Seriously ill person who needs immediate medical care
- Current anti-TB treatment (preventive TB treatment permitted)
- Lesotho only: Pregnancy (self-reported)
Trial locations and contacts
2 sites in 2 countries.
2 sites in 2 countries
South Africa1 site
Human Sciences Research Council
Pietermaritzburg, KwaZulu-Natal
About this study
According to WHO, about 40% of the incident TB cases in 2020 are either under-reported or under-diagnosed causing on one hand major health risks and on the other hand catastrophic financial consequences. In particular, indigent people in hard-to-reach communities with high TB/HIV burden are at high risk of missed or delayed diagnoses. Hence, active case finding for TB remains an integral part of tuberculosis control in high-risk groups, such as people living with HIV (PLHIV) or diabetes mellitus, people living in specific geographical locations associated with a high burden of TB and poor access to health care, miners, or prisoners. CAD4TB (Delft Imaging, NL), a digital chest X-ray analysis software, and point-of care C-reactive protein assay (POC-CRP; e.g. LumiraDx, UK), which detects a cytokine induced acute phase protein, are two tests which have great potential of becoming a screening and triage test for TB as outlined in the WHO target product profiles. Data on CAD4TB and CRP suggest that accuracy can be improved if thresholds are stratified by patient characteristics, such as HIV status, history of TB and TB symptoms. TB TRIAGE+ Trial takes place in the communities of Lesotho and South Africa, which present high prevalence of subclinical TB, where a symptom-based screening would miss almost half of all infectious TB cases. TB TRIAGE+ Trials conducts a direct (in the same individual) comparison of the two screening/triaging approaches which are not based on symptoms: CAD4TB screening alone (approach 1) versus CAD4TB screening with POC-CRP triage testing (approach 2), and followed by confirmatory Xpert MTB/RIF Ultra testing in both approaches. TB TRIAGE TRIAL is investigates the hypothesis that a community-based active case finding strategy with CAD4TB screening with POC-CRP triage testing (approach 2) will be non-inferior compared to CAD4TB screening alone (approach 1) with regard to yield of detected TB cases and superior with regard to cost effectiveness.
- Conditions
- Tuberculosis
- Being tested
- CAD4TB, POC-CRP, Xpert MTB/RIF Ultra
- Keywords
- Lesotho, South Africa, community-based, tuberculosis, active case findings, cost-effectiveness, CAD4TB, POC-CRP, Xpert MTB/RIF Ultra, triage, screening
- Medical subject headings
- Tuberculosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CAD4TBDiagnostic test
A posterior anterior digital chest X-ray incoporated in a mobile diagnostic unit is analysed by CAD4TB version 7 (Delft Imaging, NL). A trained and qualified person in compliance with national regulations will operate the digital chest X-ray.
POC-CRPDiagnostic test
A quantitative POC-CRP LumiraDx (LumiraDx Limited, UK) triage test will be performed by finger-prick if CAD4TB scores is within the defined threshold window of study approach 2 triage testing
Xpert MTB/RIF UltraDiagnostic test
Depending on CAD4TB (approach 1 \& 2) or POC-CRP score (approach 2) a confirmatory Xpert MTB/RIF Ultra(Cepheid, USA) rapid sputum molecular testing follows for both Mycobacterium tuberculosis complex and rifampicin resistance;
| Study group | Role | What they receive |
|---|---|---|
| Approach 1 - CAD4TB screening | Experimental | Participants with a CAD4TB version 7 (Delft Imaging, NL) score above the overall threshold (as defined for study approach 1) are eligible for Xpert MTB/RIF Ultra testing. Receives: Diagnostic Test: CAD4TB; Diagnostic Test: Xpert MTB/RIF Ultra |
| Approach 2 - CAD4TB screening with POC-CRP triage testing | Experimental | Participants with a CAD4TB version 7 (Delft Imaging, NL) score within the threshold window (between lower and upper limit threshold as defined for study approach 2), a POC-CRP LumiraDx (LumiraDx Limited, UK) test will follow as a triage test. If CRP is above the determined threshold as defined for approach 2, Xpert MTB/RIF Ultra will be performed. If the CAD4TB score is above the upper limit threshold as defined for approach 2, Xpert MTB/RIF Ultra will be performed (without further CRP testing). Receives: Diagnostic Test: CAD4TB; Diagnostic Test: POC-CRP; Diagnostic Test: Xpert MTB/RIF Ultra |
What is being measured
The primary outcome is the main question the study is designed to answer.
Yield of detected TB cases per study approach: number of positive Xpert MTB/RIF Ultra results per screening approach.
Measured: 24 Months
Cost-effectiveness of the CAD4TBv7-CRP approach using the CAD4TBv7 approach as a comparator: the costs for each positive Xpert Ultra case detected in the CAD4TBv7-CRP approach compared to the CAD4TBv7 approach
Measured: 24 Months
Secondary outcomes (4)
Extension of primary outcome: Cost-effectiveness of the CAD4TBv7-CRP approach and the CAD4TBv7 approach compared to passive case finding: cost per TB case detected
Measured: 24 Months
Equity analysis: 1. Socioeconomic status of households with actively detected TB cases compared to those with passively detected TB cases and to households with no TB cases: wealth quintiles distribution, income distribution and main source of income
Measured: 24 Months
Equity analysis: 2. Average out of pocket payments (OOP) associated with accessing TB treatment for households with identified TB cases across different wealth quintiles
Measured: 24 months
Health impact: The expected number of identified TB cases via passive case finding if the active case finding campaign had not taken place will be compared to the number of cases identified in the campaign
Measured: 24 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Sep 2022
- Study start7 Sep 2022
- Primary completion10 Dec 2024
- Study completion31 Dec 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for TuberculosisStudies of the same condition, open and under way.
- 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 N/A
- Primary purpose
- Diagnosis
- Allocation
- Non-randomised
- Intervention model
- Single group
- Model description
- In this study a paired screen-positive design is used to directly compare two screening/triage approaches in the same individual based on a paired analysis: CAD4TB screening only (approach 1) versus CAD4TB screening with POC-CRP triage algorithm (approach 2).
- Masking
- None (open label)
- Enrolment
- 20,000 participants (actual)
Sponsor and investigators
- Lead sponsor
- Klaus Reither
- Sponsor type
- University, hospital or other
- Collaborators
- SolidarMed, Institute of Tropical Medicine, Belgium, Radboud University Medical Center, Charite University, Berlin, Germany, Human Sciences Research Council
- Responsible party
- Sponsor-investigator, Klaus Reither, Swiss Tropical & Public Health Institute
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05526885
- Sponsor's protocol ID
- P1685-22B
- Status last verified
- Sep 2025
- First submitted
- 31 Aug 2022
- Last updated
- 22 Sep 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: All data will be stored securely in a way that allows future access for the research team. We will adhere to the FAIR Guiding Principles for data management and stewardship. After completion of the studies and after anonymization (e.g. replace subject identifier with a new random subject identifier), analysis datasets will be made publicly available in a timely manner on a non-commercial data platform according to the FAIR principles.
Publications
Signorell A, van Heerden A, Ayakaka I, Jacobs BK, Antillon M, Tediosi F, Verjans A, Brugger C, Harkare HV, Labhardt ND, Bosman S, Kamele M, Keitseng M, Madonsela T, Kurscheid J, Muhairwe J, Keter AK, Murphy K, van Ginneken B, Gils T, Katende B, Gebresenbet RF, Erhardt RM, Zoller T, Vanobberghen F, Glass TR, Lynen L, Reither K. Effectiveness and cost-effectiveness of community-based TB screening algorithms using computer-aided detection (CAD) technology alone compared with CAD combined with point-of-care C reactive protein testing in Lesotho and South Africa: protocol for a paired screen-positive trial. BMJ Open. 2025 Jul 28;15(7):e093989. doi: 10.1136/bmjopen-2024-093989.
PubMed 40721262Pita TP, Misra S, Madonsela T, Tshazi A, Bosman S, Ayakaka I, Vlieghe E, Decroo T, Reither K, van Heerden A, Gils T. "If your CD4 count lowers, that is when you are similar to a person that is non-existent" A qualitative exploration of perceptions around advanced HIV disease in South Africa. BMC Public Health. 2025 Jul 3;25(1):2325. doi: 10.1186/s12889-025-23588-1.
PubMed 40610975
Study at a glance
From the registry record, last updated by the sponsor on 22 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Tuberculosis Diagnostic Trial of CAD4TB Screening Alone Compared to CAD4TB Screening Combined With a CRP Triage Test, Both Followed by Confirmatory Xpert MTB/RIF Ultra in Communities of Lesotho and South Africa
- ClinicalTrials.gov ID
- NCT05526885
- Acronym / sponsor ID
- P1685-22B
- Conditions
- Tuberculosis
- Keywords
- Lesotho, South Africa, community-based, tuberculosis, active case findings, cost-effectiveness, CAD4TB, POC-CRP
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20,000 participants (actual)
- Lead sponsor
- Klaus ReitherUniversity, hospital or other
- Collaborators
- SolidarMed, Institute of Tropical Medicine, Belgium, Radboud University Medical Center, Charite University, Berlin, Germany, Human Sciences Research Council
- Study start
- 7 Sep 2022 (actual)
- Primary completion
- 10 Dec 2024 (actual)
- Study completion
- 31 Dec 2024 (actual)
- First posted
- 2 Sep 2022 (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.
According to WHO, about 40% of the incident TB cases in 2020 are either under-reported or under-diagnosed causing on one hand major health risks and on the other hand catastrophic financial consequences. In particular, indigent people in hard-to-reach communities with high TB/HIV burden are at high risk of missed or delayed diagnoses. Hence, active case finding for TB remains an integral part of tuberculosis control in high-risk groups, such as people living with HIV (PLHIV) or diabetes mellitus, people living in specific geographical locations associated with a high burden of TB and poor access to health care, miners, or prisoners. CAD4TB (Delft Imaging, NL), a digital chest X-ray analysis software, and point-of care C-reactive protein assay (POC-CRP; e.g. LumiraDx, UK), which detects a cytokine induced acute phase protein, are two tests which have great potential of becoming a screening and triage test for TB as outlined in the WHO target product profiles. Data on CAD4TB and CRP suggest that accuracy can be improved if thresholds are stratified by patient characteristics, such as HIV status, history of TB and TB symptoms. TB TRIAGE+ Trial takes place in the communities of Lesotho and South Africa, which present high prevalence of subclinical TB, where a symptom-based screening would miss almost half of all infectious TB cases. TB TRIAGE+ Trials conducts a direct (in the same individual) comparison of the two screening/triaging approaches which are not based on symptoms: CAD4TB screening alone (approach 1) versus CAD4TB screening with POC-CRP triage testing (approach 2), and followed by confirmatory Xpert MTB/RIF Ultra testing in both approaches. TB TRIAGE TRIAL is investigates the hypothesis that a community-based active case finding strategy with CAD4TB screening with POC-CRP triage testing (approach 2) will be non-inferior compared to CAD4TB screening alone (approach 1) with regard to yield of detected TB cases and superior with regard to cost effectiveness.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- In this study a paired screen-positive design is used to directly compare two screening/triage approaches in the same individual based on a paired analysis: CAD4TB screening only (approach 1) versus CAD4TB screening with POC-CRP triage algorithm (approach 2).
| Arm | Type | Receives |
|---|---|---|
| Approach 1 - CAD4TB screening | Experimental | Diagnostic Test: CAD4TB, Diagnostic Test: Xpert MTB/RIF UltraParticipants with a CAD4TB version 7 (Delft Imaging, NL) score above the overall threshold (as defined for study approach 1) are eligible for Xpert MTB/RIF Ultra testing. |
| Approach 2 - CAD4TB screening with POC-CRP triage testing | Experimental | Diagnostic Test: CAD4TB, Diagnostic Test: POC-CRP, Diagnostic Test: Xpert MTB/RIF UltraParticipants with a CAD4TB version 7 (Delft Imaging, NL) score within the threshold window (between lower and upper limit threshold as defined for study approach 2), a POC-CRP LumiraDx (LumiraDx Limited, UK) test will follow as a triage test. If CRP is above the determined threshold as defined for approach 2, Xpert MTB/RIF Ultra will be performed. If the CAD4TB score is above the upper limit threshold as defined for approach 2, Xpert MTB/RIF Ultra will be performed (without further CRP testing). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Willing and able to provide signed written consent or witnessed oral consent in the case of illiteracy, prior to undertaking any study-related procedure
- Adults (≥18 years)
Key exclusion criteria (4 listed)
- Any condition for which participation in the study, as judged by the investigator or a designated staff member, could compromise the well-being of the subject or prevent, limit or confound protocol specified assessments
- Seriously ill person who needs immediate medical care
- Current anti-TB treatment (preventive TB treatment permitted)
- Lesotho only: Pregnancy (self-reported)
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 |
|---|---|---|
| CAD4TBA posterior anterior digital chest X-ray incoporated in a mobile diagnostic unit is analysed by CAD4TB version 7 (Delft Imaging, NL). A trained and qualified person in compliance with national regulations will operate the digital chest X-ray. | Diagnostic test | Approach 1 - CAD4TB screening, Approach 2 - CAD4TB screening with POC-CRP triage testing |
| POC-CRPA quantitative POC-CRP LumiraDx (LumiraDx Limited, UK) triage test will be performed by finger-prick if CAD4TB scores is within the defined threshold window of study approach 2 triage testing | Diagnostic test | Approach 2 - CAD4TB screening with POC-CRP triage testing |
| Xpert MTB/RIF UltraDepending on CAD4TB (approach 1 \& 2) or POC-CRP score (approach 2) a confirmatory Xpert MTB/RIF Ultra(Cepheid, USA) rapid sputum molecular testing follows for both Mycobacterium tuberculosis complex and rifampicin resistance; | Diagnostic test | Approach 1 - CAD4TB screening, Approach 2 - CAD4TB screening with POC-CRP triage testing |
Primary outcome
Yield of detected TB cases per study approach: number of positive Xpert MTB/RIF Ultra results per screening approach.
Time frame: 24 Months
Cost-effectiveness of the CAD4TBv7-CRP approach using the CAD4TBv7 approach as a comparator: the costs for each positive Xpert Ultra case detected in the CAD4TBv7-CRP approach compared to the CAD4TBv7 approach
Time frame: 24 Months
4 secondary outcomes
Extension of primary outcome: Cost-effectiveness of the CAD4TBv7-CRP approach and the CAD4TBv7 approach compared to passive case finding: cost per TB case detected
Time frame: 24 Months
Equity analysis: 1. Socioeconomic status of households with actively detected TB cases compared to those with passively detected TB cases and to households with no TB cases: wealth quintiles distribution, income distribution and main source of income
Time frame: 24 Months
Equity analysis: 2. Average out of pocket payments (OOP) associated with accessing TB treatment for households with identified TB cases across different wealth quintiles
Time frame: 24 months
Health impact: The expected number of identified TB cases via passive case finding if the active case finding campaign had not taken place will be compared to the number of cases identified in the campaign
Time frame: 24 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Sep 2025.
- Results publication: PubMed 40721262Signorell A, van Heerden A, Ayakaka I, Jacobs BK, Antillon M, Tediosi F, Verjans A, Brugger C, Harkare HV, Labhardt ND, Bosman S, Kamele M, Keitseng M, Madonsela T, Kurscheid J, Muhairwe J, Keter AK, Murphy K, van Ginneken B, Gils T, Katende B, Gebresenbet RF, Erhardt RM, Zoller T, Vanobberghen F, Glass TR, Lynen L, Reither K. Effectiveness and cost-effectiveness of community-based TB screening algorithms using computer-aided detection (CAD) technology alone compared with CAD combined with point-of-care C reactive protein testing in Lesotho and South Africa: protocol for a paired screen-positive trial. BMJ Open. 2025 Jul 28;15(7):e093989. doi: 10.1136/bmjopen-2024-093989.
- Derived from this study: PubMed 40610975Pita TP, Misra S, Madonsela T, Tshazi A, Bosman S, Ayakaka I, Vlieghe E, Decroo T, Reither K, van Heerden A, Gils T. "If your CD4 count lowers, that is when you are similar to a person that is non-existent" A qualitative exploration of perceptions around advanced HIV disease in South Africa. BMC Public Health. 2025 Jul 3;25(1):2325. doi: 10.1186/s12889-025-23588-1.
- Project websiteLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. All data will be stored securely in a way that allows future access for the research team. We will adhere to the FAIR Guiding Principles for data management and stewardship. After completion of the studies and after anonymization (e.g. replace subject identifier with a new random subject identifier), analysis datasets will be made publicly available in a timely manner on a non-commercial data platform according to the FAIR principles.
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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.
The record lists no contact. Use the official record to reach the sponsor.
2 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing CAD4TB, POC-CRP and Xpert MTB/RIF Ultra in people with Tuberculosis, run by Klaus Reither at 2 sites in 2 countries.
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 2 inclusion and 4 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 22 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Lesotho, South Africa. 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 is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Yield of detected TB cases per study approach: number of positive Xpert MTB/RIF Ultra results per screening approach. (time frame: 24 Months). The study lists 2 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 NCT05526885, which also lists 2 linked publications.
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 22 Sep 2025.