The Jenner Institute at the University of Oxford is conducting a new study, using Bacillus Calmette-Guérin (BCG), which is the approved vaccine against tuberculosis. In this study, the aim is to administer BCG a second time to people who have already had BCG once before. In doing so, the researchers will compare whether giving the vaccine by inhalation is better at protecting people against tuberculosis than injecting it into the skin.
The BCG vaccine works well against disease in childhood, but it is not good enough at protecting against disease in adulthood, which is when the majority of TB deaths occur. Developing a new way of optimizing the BCG vaccine could improve the health of people all over the world.
As the natural route of infection with tuberculosis is through inhalation of droplets into the lungs, this study seeks to deliver BCG by the same route. By these means it is hoped that the vaccine is better at stimulating the immune system.
Commenting on the trial, Professor Helen McShane Chief Investigator, TB Vaccine Trials Jenner Institute, University of Oxford, states: “TB kills more people than any other infectious disease and we urgently need better vaccines. This important new study will help us to see whether giving BCG more than once stimulates a stronger immune response and whether giving it by inhalation is better than giving it into the skin. Small studies like these are really important to help us understand the immune response in people and allow us to design and test better vaccines.”
This study will additionally explore whether giving people with Type 2 Diabetes BCG in the skin stimulates as strong an immune response as giving BCG in the skin to healthy people without diabetes.
It is known that people with type 2 diabetes are more likely to get TB and this may be because the BCG vaccine does not work as well in this group.
To assess this, this part of the study will recruit healthy volunteers, with and without Type 2 Diabetes, who have previously been vaccinated with BCG. The volunteers will be split into 3 groups of 12 volunteers each. All participants will be followed up for 6 months after receiving BCG with close monitoring for side effects and to evaluate the immune response.
Tuberculosis is a disease caused by the bacterium Mycobacterium tuberculosis and it remains one of the top 10 causes of death worldwide, and the largest infectious agent killer. BCG given as a single dose under the skin, is the only vaccine currently licenced for use against TB, but it is not always protective.