According to the final analysis, 13 people in the vaccine group progressed to active TB, compared with 26 in the placebo group, for a 49.7% effectiveness level.
GSK's M72/AS01E candidate vaccine contains the M72 recombinant fusion protein, derived from two Mycobacterium tuberculosis antigens (Mtb32A and Mtb39A), combined with the Adjuvant System AS01, which is also a component of GSK's RTS, S malaria vaccine and vaccine against shingles, Shingrix.
Apart from Tuesday's updates, this week will see a number of other major announcements on TB at the global conference in Hyderabad.
With preventive measures aimed at containing tuberculosis (TB) showing a less-than-encouraging response, scientists across the globe are of the firm opinion that the most effective way forward to combat the disease is in the use of vaccine.
The trial was conducted in TB-endemic countries - Kenya, South Africa and Zambia - and involved 3,573 HIV-negative adults between the ages of 18 and 50 years.
Touted to be the first in decades, a vaccine has proved effective in preventing dormant tuberculosis from progressing into an active disease among adults, bringing hope that a tool to fight the disease is a possibility. "As a result it is really exciting that a vaccine has been shown to improve on this natural immunity".
Dr Lewinsohn said the new vaccine had cleared a key "mid-phase development, and it is created to test both safety and to provide an early indicator of efficacy".
The Director, Clinical Research and Development, GSK, Olivier Van Der Meeren said the safety profile of the vaccine had been very acceptable and its efficacy had been very good.More news: Foxes on cloud nine as they make history at St Mary’s
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So far, the study can say that this protection works for three years. Earlier this year, the WHO warned that multidrug resistant TB could become the dominant form of the infection in Europe as well as the rest of the world.
Latent TB means the TB bacteria is present in the body but remains dormant.
Vaccine efficacy estimates increased throughout the study period, with 27.4% vaccine efficacy for year 1, 55.2% for year 2 and 60.2% for year 3, the authors said.
On Monday, the TB Alliance announced that Indian company Macleods is going to be the second generic company to be allowed to manufacture the drug Pretomanid which is used to treat highly drug-resistant TB, as part of a regimen along with Bedaquiline and Linezolid.
India has the highest TB burden in the world with just over one in four of all estimated global cases reported in that country.
"We can not eliminate TB globally unless we end it in India", said Jamhoih Tonsing, director of the International Union Against Tuberculosis and Lung Disease's office in Delhi.
The existing Bacille-Calmette-Guerin (BCG) vaccine - licensed for humans in 1921 - is only proven to be effective for children under five for limited forms of tuberculosis, scientists said at an global conference in Hyderabad. "We need to step up the pace of treatment and prevention", she said.