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GeneXpert Performance Evaluation for Linkage to Tuberculosis Care

GeneXpert Performance Evaluation for Linkage to Tuberculosis Care: The XPEL-TB Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03044158
Acronym
XPEL-TB
Enrollment
10644
Registered
2017-02-06
Start date
2018-10-22
Completion date
2022-07-31
Last updated
2025-02-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Rifampicin Resistant Tuberculosis, Tuberculosis, Pulmonary

Keywords

tuberculosis, implementation science, point-of-care, diagnostics, GeneXpert, Uganda

Brief summary

The investigators' overall objective is to assess the effectiveness, implementation and costs of a streamlined TB diagnostic evaluation strategy based around rapid, onsite molecular testing. The intervention strategy was developed based on theory-informed assessment of barriers to TB diagnostic evaluation at community health centers in Uganda and a process of engagement with local stakeholders. It includes: 1) Point-of-care molecular testing using GeneXpert as a replacement for sputum smear microscopy; 2) Re-structuring of clinic-level procedures to facilitate same-day TB diagnosis and treatment; and 3) Quarterly feedback of TB evaluation metrics to health center staff. The investigators' central hypothesis is that the intervention strategy will have high uptake and increase the number of patients diagnosed with and treated for active pulmonary TB. To test this hypothesis, the investigators will conduct a pragmatic cluster-randomized trial at community health centers that provide TB microscopy services in Uganda in partnership with the National TB Program (NTP). The investigators utilize an effectiveness-implementation hybrid design in which, concurrent with the clinical trial, the investigators will conduct nested mixed methods, health economic and modeling studies to assess 1) whether the intervention strategy modifies targeted barriers to TB diagnostic evaluation; 2) fidelity of implementation of the intervention components (i.e, the degree to which intervention components were implemented as intended vs. adapted across sites); and 3) cost-effectiveness and public health impact.

Detailed description

Aim 1: To compare patient outcomes at health centers randomized to intervention vs. standard-of-care TB diagnostic evaluation strategies. The investigators will randomize 20 community health centers to continue standard TB evaluation (routine microscopy plus referral of patients for Xpert testing per existing processes of care) or to implement the intervention strategy (1. Onsite molecular testing; 2. Re-structuring clinic-level procedures to facilitate same-day TB diagnosis and treatment; and 3. Performance feedback). The investigators will compare reach and effectiveness based on the numbers and proportions of patients (N=5500) who complete TB testing, are found to have TB, and have treatment initiated within one week of specimen provision. Aim 2: To identify processes and contextual factors that influence the effectiveness and fidelity of the intervention TB diagnostic evaluation strategy. The investigators will use quantitative process metrics to assess the adoption and maintenance over time of the core components of the intervention strategy. The investigators will also collect quantitative and qualitative data to describe the fidelity of implementation of each component and faithfulness to the conceptual model. Aim 3: To compare the costs and epidemiological impact of intervention vs. standard-of-care TB diagnostic evaluation strategies. The investigators will model the incremental costs and cost-effectiveness of intervention relative to standard-of-care TB diagnostic evaluation from the health system and patient perspective. The investigators will then construct an epidemic model of the population-level impact of the intervention strategy on TB incidence and mortality.

Interventions

DEVICEGeneXpert I

Onsite molecular testing with GeneXpert I as a replacement for microscopy

BEHAVIORALProcess re-design

Research and Uganda NTLP staff will engage health center staff in a discussion of how to re-organize clinical, laboratory and pharmacy services to enable same-day TB diagnosis and treatment.

Feedback of TB diagnostic evaluation quality indicators to health center staff

Sponsors

Makerere University
CollaboratorOTHER
Johns Hopkins Bloomberg School of Public Health
CollaboratorOTHER
London School of Hygiene and Tropical Medicine
CollaboratorOTHER
Yale University
CollaboratorOTHER
National Heart, Lung, and Blood Institute (NHLBI)
CollaboratorNIH
University of California, San Francisco
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 100 Years
Healthy volunteers
Yes

Inclusion criteria

* Site-level: Use standard (multi-day) sputum smear microscopy as the primary method of TB diagnosis * Site-level: Participate in NTP-sponsored external quality assurance (EQA) for sputum smear microscopy * Site-level: Send samples to a district or regional hospital/health center for Xpert testing * Patient-level: Initiate evaluation for active TB at a study health center

Exclusion criteria

* Site-level: Do not agree to be randomized to standard-of-care vs. intervention arms * Site-level: Perform sputum smear examination on \<150 patients per year (based on 2015 data) * Site-level: Diagnose \<15 smear-positive TB cases per year (based on 2015 data) * Patient-level: Have sputum collected for monitoring of response to anti-TB therapy * Patient-level: Have sputum collected as part of active, community-based case finding (e.g., contact tracing, community outreach campaign) * Patient-level: Referred to a study health center for TB treatment after a diagnosis is established elsewhere * Patient-level: Started on TB treatment for extra-pulmonary TB only

Design outcomes

Primary

MeasureTime frameDescription
Number Treated for Microbiologically-confirmed TB Within 14 Days After Presentation to the Health Center for TB EvaluationWithin 14 days after presentation to the health center for tuberculosis evaluationEffectiveness outcome.

Secondary

MeasureTime frameDescription
Time to Microbiologically-confirmed TBWithin 6 months of presentation to the health center for tuberculosis evaluationEffectiveness outcome. Time-to-diagnosis if microbiologically-confirmed TB.
Number Treated for TBWithin 14 days of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Time-to-treatment of Microbiologically-confirmed TBDays from initial health center visit to initiation of treatment if diagnosed, up to 6 months.Effectiveness outcome. Time-to-treatment if microbiologically-confirmed TB and treated.
Number Who Died Within 6 MonthsWithin 6 months of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number Diagnosed With Microbiologically-confirmed TBWithin 14 days after presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number Tested for TB According to National GuidelinesWithin 6 months of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number Suspected/Diagnosed With Rifampin-resistant TBWithin 6 months of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number Diagnosed and Treated for Microbiologically-confirmed TBOn the same-day of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number Diagnosed AND Treated for TBOn the same-day of presentation to the health center for tuberculosis evaluationEffectiveness outcome.
Number of Patients EnrolledPresentation to the health center for tuberculosis evaluation during the 16-month study time frameEffectiveness outcome.

Countries

Uganda

Participant flow

Participants by arm

ArmCount
Control Group
Onsite ZN or LED fluorescence microscopy + hub-based GeneXpert testing per existing protocols
5,098
Intervention
Onsite molecular testing for TB with GeneXpert + process redesign to facilitate same-day TB diagnosis and treatment + performance feedback GeneXpert: Onsite molecular testing with GeneXpert as a replacement for microscopy Process re-design: Research and Uganda NTLP staff will engage health center staff in a discussion of how to re-organize clinical, laboratory and pharmacy services to enable same-day TB diagnosis and treatment. Performance Feedback: Feedback of TB diagnostic evaluation quality indicators to health center staff
5,546
Total10,644

Baseline characteristics

CharacteristicControl GroupInterventionTotal
Age, Continuous38 years40 years40 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants0 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
5098 Participants5546 Participants10644 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
HIV infection1905 Participants2285 Participants4190 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
5098 Participants5546 Participants10644 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
0 Participants0 Participants0 Participants
Region of Enrollment
Uganda
5098 participants5546 participants10644 participants
Sex: Female, Male
Female
3112 Participants3289 Participants6401 Participants
Sex: Female, Male
Male
1986 Participants2257 Participants4243 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
154 / 3,857145 / 4,556
other
Total, other adverse events
0 / 00 / 0
serious
Total, serious adverse events
0 / 00 / 0

Outcome results

Primary

Number Treated for Microbiologically-confirmed TB Within 14 Days After Presentation to the Health Center for TB Evaluation

Effectiveness outcome.

Time frame: Within 14 days after presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Treated for Microbiologically-confirmed TB Within 14 Days After Presentation to the Health Center for TB Evaluation220 Participants
InterventionNumber Treated for Microbiologically-confirmed TB Within 14 Days After Presentation to the Health Center for TB Evaluation342 Participants
95% CI: [1.21, 2.01]
Secondary

Number Diagnosed and Treated for Microbiologically-confirmed TB

Effectiveness outcome.

Time frame: On the same-day of presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Diagnosed and Treated for Microbiologically-confirmed TB106 Participants
InterventionNumber Diagnosed and Treated for Microbiologically-confirmed TB251 Participants
Secondary

Number Diagnosed AND Treated for TB

Effectiveness outcome.

Time frame: On the same-day of presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Diagnosed AND Treated for TB199 Participants
InterventionNumber Diagnosed AND Treated for TB362 Participants
Secondary

Number Diagnosed With Microbiologically-confirmed TB

Effectiveness outcome.

Time frame: Within 14 days after presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Diagnosed With Microbiologically-confirmed TB299 Participants
InterventionNumber Diagnosed With Microbiologically-confirmed TB389 Participants
95% CI: [0.99, 1.66]
Secondary

Number of Patients Enrolled

Effectiveness outcome.

Time frame: Presentation to the health center for tuberculosis evaluation during the 16-month study time frame

Population: All eligible were enrolled as there was a waiver of informed consent

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber of Patients Enrolled5098 Participants
InterventionNumber of Patients Enrolled5546 Participants
Secondary

Number Suspected/Diagnosed With Rifampin-resistant TB

Effectiveness outcome.

Time frame: Within 6 months of presentation to the health center for tuberculosis evaluation

Population: The data analyzed included all adult patients in the target population. Those with rifampin-resistant tuberculosis, extrapulmonary tuberculosis and/or missing age data were excluded from the trial population. Therefore, the number of participants analyzed for this measure differs from other parts of the record.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Suspected/Diagnosed With Rifampin-resistant TB5 Participants
InterventionNumber Suspected/Diagnosed With Rifampin-resistant TB2 Participants
Secondary

Number Tested for TB According to National Guidelines

Effectiveness outcome.

Time frame: Within 6 months of presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Tested for TB According to National Guidelines2687 Participants
InterventionNumber Tested for TB According to National Guidelines5108 Participants
Secondary

Number Treated for TB

Effectiveness outcome.

Time frame: Within 14 days of presentation to the health center for tuberculosis evaluation

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Treated for TB339 Participants
InterventionNumber Treated for TB485 Participants
95% CI: [1.04, 2.12]
Secondary

Number Who Died Within 6 Months

Effectiveness outcome.

Time frame: Within 6 months of presentation to the health center for tuberculosis evaluation

Population: Includes those with vital status follow-up at six months post-visit to health center

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Control GroupNumber Who Died Within 6 Months123 Participants
InterventionNumber Who Died Within 6 Months116 Participants
95% CI: [0.44, 1.35]
Secondary

Time to Microbiologically-confirmed TB

Effectiveness outcome. Time-to-diagnosis if microbiologically-confirmed TB.

Time frame: Within 6 months of presentation to the health center for tuberculosis evaluation

Population: All participants' data was analyzed to determine who had confirmed TB.

ArmMeasureValue (MEDIAN)
Control GroupTime to Microbiologically-confirmed TB0 days
InterventionTime to Microbiologically-confirmed TB0 days
95% CI: [0.39, 0.62]
Secondary

Time-to-treatment of Microbiologically-confirmed TB

Effectiveness outcome. Time-to-treatment if microbiologically-confirmed TB and treated.

Time frame: Days from initial health center visit to initiation of treatment if diagnosed, up to 6 months.

Population: All participants' data was analyzed to determine who had confirmed TB and treatment initiated.

ArmMeasureValue (MEDIAN)
Control GroupTime-to-treatment of Microbiologically-confirmed TB1 days
InterventionTime-to-treatment of Microbiologically-confirmed TB0 days
95% CI: [0.21, 0.56]

Source: ClinicalTrials.gov · Data processed: Feb 27, 2026