Key TB Vaccine Trial Fails
New vaccine provides no extra protection for infants after BCG (Feb. 4)
A new vaccine against tuberculosis (TB) developed at Oxford University in the U.K. — the TB vaccine most advanced in clinical trials — has been found not to offer extra protection against the disease in infants previously given the Bacille Calmette-Guérin (BCG) vaccine.
The phase IIb trial was the first to evaluate the ability of a new TB vaccine to prevent the disease since the BCG vaccine was introduced 90 years ago.
The study involved approximately 2,800 infants in South Africa, and the findings were published in The Lancet.
“The primary endpoint of the trial was safety, and we met this endpoint and found the vaccine to be safe,” said senior author Professor Helen McShane. “However, unfortunately, we saw no statistically significant evidence of increased protection against TB above and beyond BCG alone.”
McShane first developed the new vaccine — MVA85A — 15 years ago.
TB is the second most deadly infectious disease in the world. In 2011 there were approximately 8.7 million new cases of TB and 1.4 million deaths worldwide.
Approximately 100 million newborns are vaccinated globally with the BCG vaccine each year. This vaccine, however, does not prevent TB bacteria from affecting the lungs — the most common form of the disease in adolescents and adults — and TB remains a global epidemic.
Source: University of Oxford; February 4, 2013.