CHENNAI: Scientists at ICMR’s National Institute for Research in Tuberculosis in Chennai plan to initiate a study on BCG booster dose for children and adolescents who are household contacts of tuberculosis patients. The aim of the study is to understand whether a booster dose of BCG can prevent the development of tuberculosis in them. For this, more than 9,000 children will be enrolled across seven sites in India.
The primary objective of this study is to assess the efficacy of BCG re-vaccination compared to oral chemoprophylaxis in preventing tuberculosis (TB) in household contacts aged 6–18 years. Children will be randomized into 2 study groups: BCG and oral chemoprophylaxis.
The Bacille Calmette Guerin (BCG) vaccine is one of the most widely used vaccines in the world to reduce the risk of natural tuberculosis infection. The efficacy of BCG vaccination in newborns is well known and has a protective effect against meningitis and disseminated TB in children.
However, there is considerable uncertainty over BCG vaccination. It is known that BCG vaccination enhances the immune response, but it is not yet established that BCG vaccination can help prevent TB disease in household contacts.
“The study is designed as a multicenter randomized controlled trial with two groups of healthy household contacts aged 6-18 years who received BCG vaccine or oral chemoprophylaxis. To compare the incidence of TB disease in each arm. They will be followed up for 24 months. This study will demonstrate the effect of BCG revaccination as compared to oral chemoprophylaxis on the incidence of Mycobacterium tuberculosis disease in healthy household contacts aged 6-18 years,” said Dr. C Padmapriyadarshini, Director, NIRT. Told Mint.
“ICMR has held a round of talks with the health ministry and another meeting is to be held next week. As of now, there is no data on how many children in this age group develop TB and how many die due to this disease,” said Dr C Padmapriyadarshini.
“All children will be household contacts of microbiologically confirmed pulmonary TB patients. Contacts of adults with multidrug-resistant (MDR) TB will also be included in the study. Both the C-TB skin test positive and negative will be included in children. Similarly both malnourished and malnourished children will be included. All children would be followed up for 24 months after recruitment and the incidence of TB (all forms) between groups would be compared. The diagnosis of TB will be done as per the National TB Elimination Program (NTEP) and latent TB infection (LTBI) will be based on the results of the C-TB skin test.
The scientists are aiming to start the study as soon as they wait for the funds to be released. They have set a target of completing the study by 2025 to match the deadline of the Ministry of Health’s TB eradication target by 2025.