GlaxoSmithKline has announced that its IAVI-partnered experimental tuberculosis (TB) vaccine candidate significantly reduced the occurrence of pulmonary tuberculosis disease.
The impressive results showed that M72/AS01E demonstrated an overall vaccine efficacy of 50% during the three years after patients received the vaccine. According to GSK, the vaccine has an acceptable safety and reactogenicity profile.
The trial took place in TB-endemic regions (Kenya, South Africa and Zambia), and involved 3,573 HIV-negative adults between the ages of 18 and 50 years. The participants, who received two doses of either M72/AS01E or placebo, were observed for three years to detect evidence of TB.
The final analysis of the data showed that 13 participants in the vaccine group developed TB compared to 26 participants in the placebo group. Also among those who received the vaccine was an increased M72-specific immune response which was sustained throughout the duration of those three years.
“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,” said Thomas Breuer, chief medical officer of GSK vaccines.
“I want to thank our scientists for their dedicated effort and scientific innovation in developing this impactful vaccine candidate in partnership with IAVI and other key organisations,” he added.
An estimated one-quarter of the global population has latent TB infection, with approximately 10% going on to develop the active form of the disease.
There are multi-drug resistant strains of TB – a form of the disease which is unresponsive to at least two of the first-line of anti-TB drugs – emerging globally, with the only available vaccine, BCG, not providing a proven and consistent protection in adults in TB-endemic countries.
According to GSK, a more effective vaccine is needed to achieve the World Health Organization’s target of decreasing the number of new cases by 90% and the number of TB deaths by 95% between 2015 and 2035. The aim is to develop the vaccine so that it can provide long-term protection against the disease, including resistant strains.
“These final results show that M72/AS01E could be an important tool in the fight against pulmonary tuberculosis,” said Mark Feinberg, president and CEO of IAVI.
“While additional trials need to be conducted to confirm these findings in other populations, we have never before seen a vaccine that provides protection in adults who are already infected with the bacteria that cause tuberculosis,” he added.
GSK has made vaccines a pillar of its strategy since taking control of Novartis’ vaccine business in 2014, which it then followed up with a $190m deal for vaccine specialist GlycoVaxyn in 2015.
In an analyst call earlier this year, GSK head of global vaccines Roger Connor said that the company is particularly excited about the three respiratory syncytial virus (RSV) vaccines coming through development – one for children, one for maternal use, and one for older adults – and a therapeutic vaccine targeting bacteria that cause exacerbations in chronic obstructive pulmonary disease (COPD).