Ruben, a senior scientist working in the tuberculosis imaging laboratory at Tres Cantos, Madrid

TB: uniting scientists to tackle one of the world’s biggest killers

Tuberculosis – better known as TB – is one of the top ten causes of deaths worldwide. But for the first time in almost 100 years, we have taken a major step towards finding a potential new vaccine against the disease.

Known for its fever and sometimes coughing up blood, TB was once believed to be under control – consigned to Victorian novels rather than a fixture of modern life. But this potentially fatal disease has roared back; and now there are 10 million cases a year.

There are several reasons why TB has rebounded. One is the lengthy and complicated course of antibiotics that is the current treatment for many infections. Typically, patients might take up to four different medicines, for six to nine months. 

Around 20-30% of patients do not finish their treatment and this creates opportunities for deadlier, drug-resistant strains to develop. Combined with the lack of new treatment options in recent years, this has contributed to a surge of new cases of TB.

  • 4000

    lives are claimed by TB every day, according to the World Health Organization (WHO)

Against this backdrop, the WHO has set an ambitious target of reducing the number of TB deaths by 95% between 2015 and 2035, warning that failure to end TB will carry serious individual and global public health consequences. [1]

But the current ammunition is not sufficient to put a stop to TB for good. If the global community is to achieve the WHO’s goal, then it needs to find new and better diagnosis and treatment options – and a more effective vaccine.

The search for a new vaccine

Human blood cells infected by TB bacteria
Human blood cells infected by mycobacterium tuberculosis (MTB), the bacteria that can cause TB.

Currently, there is only one TB vaccine available – the Bacillus Calmette–Guérin vaccine, better known as the BCG. Given to babies, the vaccine prevents severe disease in children but its effectiveness against pulmonary TB in adults varies. The BCG vaccine plays an essential role to protect babies in TB endemic countries, but it is not enough to control the disease at a global scale.

“Developing a new vaccine for TB is tough. It is a very complex disease and presents major challenges,” explained Emmanuel (Manu) Hanon, Senior Vice President, Head of Vaccines R&D, GSK.

Mycobacterium tuberculosis (MTB) – the bacteria that can cause TB – is unique. “These bacteria have the amazing ability to remain latent in their host by creating a kind of niche micro-environment, protecting them from our immune system,” added Manu.

“This means that it is even harder to displace the bacteria with a vaccine. What’s more, the unique latency mechanism cannot really be reproduced in laboratory so the only way to find a potential vaccine against TB is through clinical trials with very large numbers of participants. This is exactly what we are doing.”

TB vaccine researcher in the lab
A TB vaccine researcher at the Aurum Institute for Health Research - Thembisa Hospital, South Africa

Over the last 15 years, we have been working with Aeras, a not-for-profit biotech, to develop a TB candidate vaccine, with the support of the Bill & Melinda Gates Foundation, the UK’s Department for International Development and others.

Our candidate vaccine is currently being tested in a phase II clinical trial in TB-endemic regions of Africa. Primary results after a two-year follow-up of the study’s participants, published in the New England Journal of Medicine, showed the candidate vaccine could help prevent adults with latent TB infection from becoming sick with pulmonary TB. The study is still ongoing and is expected to complete at the end of 2018; and the analysis of the final study results is planned for 2019.

For the first time in almost a century, we have taken a major step towards finding a potential new vaccine for TB.

It is a great example of using our scientific expertise to find new vaccines against some of the biggest health threats and to build fruitful partnerships to enable their development.

Joining forces to fight TB

Developing a vaccine is not the only field in which GSK is teaming up with others to fight TB.

Potential new medicines are being developed in our R&D unit in Tres Cantos, Spain – a site where GSK and visiting scientists collaborate on research dedicated to developing treatments for diseases that disproportionately affect developing countries.

“As with other global health challenges such as HIV or malaria, we must work together to combat TB,” said Pauline Williams, SVP, Global Health R&D at GSK. “Sharing information and scientific expertise and building public-private partnerships will help address some of the barriers to the development of a new generation of TB interventions.”

Eugenia, scientist, working at Tres Cantos
Eugenia, a senior scientist working in the tuberculosis biology laboratory at Tres Cantos, Madrid

GSK is an active member of several collaborations focused on developing new treatments for TB, including multi-drug resistant forms of the infection. In 2012, we joined the TB Drug Accelerator Program – a partnership with a number of other pharmaceutical and public sector research institutions and the Bill & Melinda Gates Foundation, aiming to speed up the discovery of new medicines by collaborating on early stage research. We are also part of Predict TB, one of the world’s only initiatives focused on tackling some of the very early-stage barriers to the discovery of new TB treatments.

In 2012, our scientists screened our entire library of more than two million compounds – the building blocks of future medicines – for any showing signs of activity against TB. The 200 compounds subsequently identified were made freely available online, for external scientists to carry out their own research. To date, we have shared copies of these compounds with 30 research groups around the world, who are also working to tackle TB.

“When the best scientific minds join forces, we can make great strides in improving global health,” said Pauline.

“We believe that researching TB medicines is an area where we can achieve a united front – opening up our labs, and sharing our resources, our data and our expertise – and help save lives.”

[1] http://www.who.int/tb/strategy/end-tb/en/