New TB vaccine has 50% protection against progression to active disease
A path breaking development has brought the world a step closer to a better vaccine against tuberculosis (TB), as researchers today published final results from a phase 2b trial, which showed nearly 50% protection against progression to active TB.
Tuberculosis is the world's deadliest infectious disease that claimed some 1.5 million lives last year particularly in developing countries.India accounts for a quarter of the world's TB cases and Prime Minister Narendra Modi has set an ambitious target of ending the epidemic by 2025.
The existing Bacille-Calmette-Guerin (BCG) vaccine is only proven to be effective for children under five for limited forms of tuberculosis, its protection varies widely in adults. Demand for a better vaccine has been rising, especially in the face of rising levels of multidrug-resistant TB.
Studies suggest that a vaccine targeted to adolescents and adults would be the strongest tool to cut levels of TB.
Scientists are closing in on a new game-changing vaccine for tuberculosis.The trial conducted in three African nations by GlaxoSmithKline has revealed that its vaccine had 50 percent effectiveness three years after it was given to participants who already had TB bacteria but have not fallen ill from the disease.
The results have to be further tested in longer and larger trials across broader ranges of populations and countries, the scientists said in the New England Journal of Medicine, where the report was published.
"These results demonstrate that for the first time in almost a century, the global community potentially has a new tool to help provide protection against TB," GSK Vaccines' chief medical officer Thomas Breuer said in a statement released at a conference on lung health in Hyderabad, India.
Campaigners said the trial in Kenya, South Africa and Zambia, involving more than 3,000 adults, was a crucial step amid a push for more funding for TB research.
South African Tuberculosis Vaccine Initiative director Mark Hatherill said a vaccine would be "the only way in the short-term to interrupt TB transmission and get control of the epidemic."
Ann Ginsberg, of the International AIDS Vaccine Initiative which has been taking part in the research, said 15 possible vaccines are at various stages of development around the world but this was the most "exciting".
If successful, the vaccine could "avert tens of millions of new cases of TB and save millions of lives globally."
"We are one more cautious, but exciting, step closer to a vaccine for tuberculosis," said Paula Fujiwara, scientific director of the Paris-based International Union Against Tuberculosis and Lung Disease.
Breuer said it would take several years to complete the trials and get a licence for a vaccine.
About one in four people worldwide carry latent TB, meaning they are infected with the bacteria but are not sick and cannot transmit the disease.
Between five to 15 percent develop active TB. Those with compromised immune systems such as people with HIV are more vulnerable to falling sick.
The announcement came as thousands of researchers, TB survivors and activists gathered in the southern Indian city of Hyderabad for a global conference on lung health.
For further reference log on to:
Dereck R. Tait et al. Final Analysis of a Trial of M72/AS01E Vaccine to Prevent Tuberculosis, New England Journal of Medicine (2019). DOI: 10.1056/NEJMoa1909953
Journal information: New England Journal of Medicine
active disease against BCG better vaccine effective infants its protection varies widely in adults. Demand for a new progression protection TB vaccine young childrenSource : New England Journal of Medicine