New TB vaccine tested on mice shows promise
Tuberculosis is a disease caused by the Mycobacterium tuberculosis (Mtb) bacteria, and is the world’s leading killer due to infection according to the WHO.
The BCG (bacille-Calmette-Guerin) vaccine – delivered by an intramuscular injection in the upper arm – is made to use against Mtb infections; some 70-80% effective against more severe forms such as TB meningitis in children, but less effective in preventing respiratory disease in adults. However, BCG cannot be given to immune-compromised patients – people with HIV/AIDS who are at a greater risk of developing a fatal infection if infected with latent TB.
A vaccine for this population, then, has the potential to save millions of lives.
Professor Jordi Torrelles of Texas Biomedical Research Institute has experimented on a modified BCG vaccine for this purpose. The idea was to provide the immune cells with better memory response to recognise and kill only the specific Mtb bacteria in the lungs.
Previous attempts to vaccinate intranasally have resulted in lung inflammation and tissue damage. But the inflammation rate was only 8% with the modified BCG as compared to 20% with BCG.The modified formulation does not cause any lung tissue damage, and possible drug delivery could be through a spray.
Torrelles has predicted that the modified BCG vaccine may offer immunity at any age, but must still be tested on larger animals before any human clinical trials can be conducted.
Category: Features, Pharmaceuticals