TB is a disease caused by the bacterium Mycobacterium tuberculosis and in 2023 was the leading cause of death from an infectious disease globally. The only current licensed vaccine against TB is Bacillus Calmette-Guérin (BCG), which has remained unchanged for over a century. BCG is a weakened form of Mycobacterium bovis, which is very similar to Mycobacterium tuberculosis and is normally given as an injection in the skin at birth in areas with endemic TB. Although BCG is safe to give to infants, it does not provide life-long protection and drugs against TB are not enough to stop the financial and social burden of TB. An effective vaccine is urgently needed to reduce the spread of TB, prevent progression to active disease, and save lives.
The Jenner Institute is developing a pioneering human challenge model to test new TB vaccines. A challenge model is used to test if new vaccines work, before larger field (efficacy) studies. These models have been used to test other vaccines such as malaria, where volunteers are purposefully given malaria after the trial vaccine to see if the vaccine works.
Professor Helen McShane, Professor of Vaccinology at NDM's Jenner Institute, said: ‘The only vaccine we currently have against TB is the BCG, which unfortunately is not very effective against lung TB. We are looking at ways to deliver vaccine to the cells that will first to encounter TB bacteria, and this trial should give us important information about how our lungs respond to the early stages of infection. It will also be vitally important in the development of inhaled vaccines, which could be a much more effective way of protecting against many respiratory illnesses.’
This is the first time an aerosol BCG-challenge model will be used to test a new TB vaccine. The study is funded by the National Institute of Health’s National Institute of Allergy and Infectious Diseases as part of the IMPAc-TB consortium and is being conducted in collaboration with SCRI. The team is looking for healthy volunteers, both those who have had a BCG vaccine, and those who have never had a BCG vaccine.
Please see the Jenner website for more information and the application questionnaire: https://www.jenner.ac.uk/volunteer/recruiting-trials/tb045