TB vaccine shows early promise as world leaders gather to discuss wiping out disease

The first new vaccine for preventing tuberculosis in more than 100 years has shown promising results in clinical trials.

In a trial of around 3,500 adults in Kenya, South Africa and Zambia the study showed that the vaccine cut the number of people developing TB by half compared to those in the group that did not receive the vaccine. In the vaccine group 10 people developed TB compared to 22 who received a placebo.

While these numbers are small those in the group that did not receive the vaccine reflect the proportion of people in these countries where TB is endemic that would go onto develop TB over that amount of time.

Latest figures from the World Health Organization (WHO) show that 10 million people contracted TB in 2017, and 1.6million of those people died. Development of an effective vaccine is seen as crucial to hitting WHO targets on slashing the number of new cases of the disease by 90 per cent and deaths by 95 per cent between 2015 and 2035.

The BCG vaccination, which was routinely given to all UK school children up until 2005, only provides protection among children, not adults.

The study is published the day before world leaders gather at the United Nations general assembly to discuss efforts to wipe out the disease. TB experts and activists hope the meeting will prove a catalyst for eradication of the world's leading infectious disease killer.

Adults aged up to 50 were given the M72/AS01 vaccine - developed by UK pharmaceutical giant GSK and non-profit TB vaccine developer Aeras - in two doses, 30 days apart. They were then followed up for at least two years to detect evidence of pulmonary TB.

The data, published in the New England Journal of Medicine, are initial findings and need to be confirmed in a final analysis when the study concludes next year.

Emmanuel Hanon, senior vice president and head of research and development for global vaccines at GSK, described the findings as a “scientific breakthrough”.

“These initial findings represent a significant innovation in the development of a new and much-needed and advance the scientific understanding of tuberculosis,” he said.

It is likely to be several years before the vaccine is ready to be used in any real-life setting, said Dr Hanon.

“There are several questions that we must still address, including whether it works in people with HIV. If we want to cut the disease and transmission we need to know what is going to be the best intervention and what will be the best population to target,” he said.

Development of a vaccine is also important in the fight against drug-resistant TB, said Dr Hanon.

He added: “The vaccine is potentially the start of a solution to a big problem.”

Mike Turner, head of infection and immunobiology at the Wellcome Trust, said: “ This new vaccine is a landmark moment in the effort to make progress against a global killer.

"This candidate vaccine could prevent over half of those who are vaccinated from developing TB and could also curb the transmission of the disease.

"The next steps for this new vaccine will be to test it in much larger numbers of people and to establish if it can protect young children or those who are HIV positive,” he said.

Richard White, professor of infectious disease modelling at the London School of Hygiene & Tropical Medicine, said the vaccine held great promise.

“This is exciting because it suggests that, for the first time, we may be able to develop a vaccine that we can give to adults with TB infection, to prevent TB disease. If it works globally, this would be a game changer for global TB prevention.

“The journey towards a new TB vaccine for adults has lasted around 100 years. More research is required, but the results of this ground-breaking study mean there is hope in the search for new effective TB vaccines,” he said. 

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