A Trial of the C-Tb Skin Test, When Given Intradermally to Adult Patients Recently Diagnosed With Active Tuberculosis (TB)
Condition: Tuberculosis
MeSH terms: Tuberculosis
Study type: Interventional
Phase: Phase 2

Summary: 
      Tuberculosis (TB) continues to be the most important bacterial infection worldwide and
      therefore new improved diagnostic tests are needed to help doctors in diagnosing TB.

      The new skin test is named C-Tb. Like the current Tuberculin Skin Test (TST), the C-Tb test
      is injected just under the skin and will when positive show a redness and/or swelling at the
      injection site while a negative test will leave no reactions.

      The aim of this trial is to test the C-Tb skin test in adults diagnosed with TB to determine
      if a TB infected individual has a truly positive test result (this is called to find the
      sensitivity of the skin test).
    

Detailed description: 
      The trial is designed to investigate the sensitivity of C-Tb using various sizes of cut-off
      of induration in a double blind randomised, split-body study comparing 0.1 µg/0.1 mL C-Tb
      with the reference agent 2 T.U. Tuberculin PPD RT23 SSI. (Each volunteer receives the C-Tb
      agent in one arm and 2 T.U. Tuberculin PPD RT 23 SSI in the other arm). Two groups of adult
      patients recently diagnosed with active TB will be investigated; patients in the main group
      will NOT have a co-infection with HIV and patients in the second group will have a
      co-infection with HIV.

      The C-Tb and 2 TU Tuberculin PPD RT 23 SSI agents are given concomitantly to each volunteer
      in the RIGHT AND LEFT forearms according to a double blind randomisation scheme.

      The primary objectives are to assess the sensitivity of the C-Tb test as a function of the
      cut-off value (i.e., the smallest size of induration measured in mm resulting in a positive
      outcome of the C-Tb test) when the test is administered intradermally by the Mantoux
      technique to HIV negative adult patients recently diagnosed with active TB and to assess the
      sensitivity of the C-Tb test as a function of the cut-off value (i.e., the smallest size of
      induration measured in mm resulting in a positive outcome of the C-Tb test) when the test is
      administered intradermally by the Mantoux technique to HIV positive adult patients recently
      diagnosed with active TB The sensitivity is defined as the relative frequency of patients
      with an induration response ≥ cut-off in TB patients.

      Similarly the specificity of the C-Tb test is defined as the relative frequency of subjects
      in a healthy population (i.e., no exposure to M. tuberculosis) who have an induration
      response < cut-off after a C-Tb test.

      An optimal cut-off point of being infected will be determined by combing the results from the
      present sensitivity study with those from a parallel specificity study in (BCG vaccinated)
      individuals with no previous exposure to M. tuberculosis.

      The secondary objectives of the trial is to compare the induration response of C-Tb with the
      induration response of 2 T.U. Tuberculin PPD RT 23 SSI, to compare the induration response of
      C-Tb with the in-vitro IFN-γ response measured at screening using the QuantiFERON®-TB Gold In
      Tube assay, to correlate the induration response to the initial CD4+ counts in HIV positive
      patients and to record all adverse events (local and systemic) occurring within 28 days after
      application of the agents
    

Intervention name(s): C-Tb; 2 TU Tuberculin PPD RT 23 SSI
Intervention type(s): Biological; Biological
Intervention description(s): The C-Tb agent is administered by the Mantoux injection technique to each volunteer in the RIGHT or LEFT forearms according to a double blind randomisation scheme; The 2 TU Tuberculin PPD RT 23 SSI agent is administered by the Mantoux injection technique to each volunteer in the RIGHT or LEFT forearms according to a double blind randomisation scheme
Other intervention name(s): rdESAT-6 + rCFP-10; PPD; Tuberculin
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Diagnostic
Keywords: tuberculosis; rdESAT-6; CFP-10; skin test; diagnostic test