Two new vaccines to prevent tuberculosis (TB) are safe to use in adults and children, but do not protect against all forms of the disease, a large trial published in India has found. BMJ today.
Tuberculosis remains a major global public health concern. In 2023, an estimated 10.8 million people worldwide will be reported to have tuberculosis, with the rate of new infections increasing by 4.6% between 2020 and 2020, highlighting the growing scale of the problem. BCG is currently the only vaccine approved for tuberculosis. However, while it is effective against severe tuberculosis in young children, it is not effective in adolescents or adults.
To address this gap, researchers in India conducted a large-scale trial to assess whether two new tuberculosis vaccines (VPM1002 and Immuvac) can protect against all forms of tuberculosis (pulmonary and extrapulmonary tuberculosis), prevent latent (dormant) infection, and generate an immune response against Mycobacterium tuberculosis.
The study enrolled 12,717 household contacts (aged 6 years and above) of recently diagnosed tuberculosis patients in 18 facilities across six states in India between July 2019 and December 2020.
Participants were randomly assigned to receive an initial dose of either VPM1002, Immuvac, or placebo (4,239 in each group) and were followed for 38 months. The second dose was administered one month later to 11,829 participants. A total of 12,295 participants (96.7% of enrollment) completed the 38-month follow-up.
Although neither vaccine provided general protection against tuberculosis or prevention of latent tuberculosis infection, both vaccines demonstrated the ability to prevent progression to active tuberculosis in patients who developed latent tuberculosis.
Researchers found that while both vaccines did not show efficacy against all tuberculosis and pulmonary tuberculosis (PTB), one of the vaccines, VPM1002, showed efficacy (50.4%) against extrapulmonary tuberculosis (EPTB) across all age groups, including those aged 36 to 60 years (79.5%). These findings suggest potentially significant public health benefits, as extrapulmonary tuberculosis, which affects organs other than the lungs, is often associated with a higher risk of death than pulmonary tuberculosis.
A promising key finding was the protective effect against tuberculosis in children, with VPM1002 providing protection against all tuberculosis, PTB, and EPTB in the 6 to <14 years group, whereas Immuvac only provided protection against EPTB in the 6 to <10 years group.
However, neither vaccine was able to protect low birth weight children or adults. This suggests that nutritional supplementation may be needed along with vaccination, especially for younger children, the authors report.
Both vaccines were found to be safe and elicit an immune response.
Researchers acknowledged that the COVID-19 pandemic affected the study, excluding some participants who missed the second shot and, in some cases, delaying follow-up. Additionally, the findings may not apply to other countries or ethnic groups.
Nevertheless, as the authors reported, this was a large, well-designed study that reflected a real-world scenario, as it included both children and adults, regardless of pre-existing conditions such as diabetes or risk factors. They conclude that further research could be conducted on commonly targeted high-risk groups for tuberculosis.
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Reference magazines:
Shin, M. others. (2026). Efficacy and safety of VPM1002 and Immuvac in tuberculosis prevention: a phase 3 randomized clinical trial (PreVenTB trial). B.M.J. DOI: 10.1136/bmj-2025-085716. https://www.bmj.com/content/393/bmj-2025-085716
