A Trial of the C-Tb Skin Test, When Given Intradermally to Healthy Volunteers Previously Vaccinated With BCG — TESEC-03  

Tuberculosis Clinical Trial

Official title: A Phase IIa Specificity Trial of the Diagnostic Agent C-Tb, When Given Intradermally by the Mantoux Technique to Healthy Volunteers Previously Vaccinated With BCG

Status Completed

Clinical Trial Summary

A new, more specific skin test to detect tuberculosis has been developed by Statens Serum Institut in Denmark. The new skin test is named C-Tb and like the current Tuberculin a positive test result will show as redness and/or swelling at the injection site, while a negative test will leave no reactions.

The aim of this study is to test the C-Tb skin test in healthy adults previously BCG vaccinated to determine if healthy non tuberculosis infected individuals has a truly negative test result (this is called determining the specificity of the skin test). To be able to compare the new skin test with the current Tuberculin skin test volunteers will be injected with both the C-Tb and the TST skin test.

Clinical Trial Description

The trial is designed to investigate the specificity of C-Tb under various definitions of cut-off 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 the 2 T.U. Tuberculin PPD in the other arm).

The C-Tb and 2 T.U. Tuberculin PPD agents are given concomitantly to each volunteer in the RIGHT AND LEFT forearm according to a double blind randomisation scheme.

The primary objective of the trial is to assess the specificity 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 negative outcome of the C-Tb test) when the test is administered intradermally by the Mantoux technique to healthy BCG vaccinated adults The specificity of the C-Tb test is defined as the relative frequency of subjects in a healthy population (i.e., no exposure to MTb) who have an induration response < cut-off after a C-Tb test.

Similarly the sensitivity is defined as the relative frequency of patients with an induration response ≥ cut-off in TB patients.

An optimal cut-off point of being infected will be determined by combing the results from the present specificity study with those from a parallel sensitivity study in patients recently diagnosed with TB.

The secondary objectives of the trial are 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 and 28 days after the injections of the skin test agents using the QuantiFERON®-TB Gold In-Tube assay and finally to record all adverse events occurring within 28 days after application of the agents. ;

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Diagnostic

Related Conditions & MeSH terms

• Tuberculosis

• NCT number: NCT01242475
• Study type: Interventional
• Source: Statens Serum Institut
• Status: Completed
• Phase: Phase 2
• Start date: April 2011
• Completion date: November 2011