TB031 BCG Challenge Study
Research type
Research Study
Full title
TB031: A clinical challenge study to quantify BCG at the challenge site of healthy volunteers receiving either intradermal BCG SSI or BCG TICE at standard or high dose
IRAS ID
146214
Contact name
Helen McShane
Contact email
Sponsor organisation
University of Oxford
Research summary
Tuberculosis (TB)is one of the leading causes of death due to an infectious disease. The development of an effective vaccine to prevent infection is a global health priority.
A major challenge in the field of TB vaccine research is to develop laboratory measures of human immune responses that correlate strongly with protection from TB in order to help distinguish between new vaccines undergoing phase 1 trials. A recent pilot study, TB015, conducted by our group, has established that the BCG ’challenge’ model is practically feasible and could be useful for identifying better correlates of protection.
The rationale behind this BCG ’challenge’ model is that we cannot use Mycobacterium tuberculosis (the bacterium that causes TB in humans) itself as a challenge agent for safety reasons, but we can use BCG, a weakened live strain of Mycobacterium bovis (the bacterium that causes TB in cattle), instead. BCG is injected under the skin just like during vaccination, and the injection site is biopsied two weeks later. The quantity of BCG remaining in the biopsy tissue is then measured.
An effective vaccine against TB should also be effective against BCG. Thus biopsies of individuals with pre-existing immunity to TB induced by vaccination should contain fewer BCG bacteria than vaccination-naïve individuals.
The study will involve giving BCG vaccine as an intradermal injection to 40 healthy volunteers. This will cause the replication of M.tb in the skin. We will then take a biopsy of the skin 14 days later to measure the growth of M.tb. Blood tests (total of 184mL) to look at the immunological markers will also be taken. We will use different strains of BCG and give it at different doses to illicit any differences in the model of infection.
This trial will take place at two sites, the CCVTM, Oxford and the WTCRF, Birmingham.
REC name
South Central - Oxford B Research Ethics Committee
REC reference
14/SC/0036
Date of REC Opinion
25 Feb 2014
REC opinion
Further Information Favourable Opinion