he Indian Council of Medical Research (ICMR) has launched India’s first large-scale trial for two new TB vaccines, a report in the IE has indicated. This is the first time a large preventive TB vaccine trial involving more than 12,000 healthy household contacts of newly diagnosed TB patients from across six states of India are set to be enrolled.
For these trials, the six states including Delhi, Maharashtra, Odisha, Telangana and Karnataka, with two thousand participants from each state are to be enrolled over the next seven to eight months. Further, seven main centres will have six sub-sites, where these trials will be conducted.
In this first of its kind roll out, the report in IE adds that candidates in this trial will be at high risk of contracting the disease. Therefore, they will be vaccinated with either of the two new vaccines, and compared with placebo to assess its efficacy.
Many questions related to tuberculosis vaccine history may already be racing through your mind. For instance, is TB vaccine necessary when BCG vaccine is already known to be effective? Can you get TB after BCG vaccine is administered?
Let’s understand more about TB vaccines in India and why new vaccines are the need of the hour.
Data shows us that TB incidence in the country is pegged at almost 2.8 million every year coupled with drug-resistant TB incidence at 1,47,000 annually. The source of this data is from the Ministry of Health and Family Welfare’s Central TB division.
A more disturbing statistic in the report pertains to the fact that India contributes to around 27 per cent of the world’s TB burden, marking the highest share at a global level. However, in 2017, the Centre committed itself to eliminate TB by the year 2025.
As you are already aware, treating TB involves multi-drug course that usually spans six months, sometimes this can be further stretched in case of treatment for drug-resistant TB.
A perusal of ICMR’s website highlights the critical need for new TB vaccines other than BCG – or Bacille Calmette-Guerin, which most of you are familiar with, as a vaccine that is now more than a hundred years old.
Also, the BCG vaccine is known to be immunoprotective against TB and TB meningitis in children, but its protection provided for pulmonary TB in adults is variable, as per ICMR. Therefore, with the persistent threat of TB incidence globally, new vaccines are the need of the hour.
The ICMR also points out that the pipeline of TB vaccines includes whole-cell derived vaccines, recombinant BCGs, and several other proteins and adjuvant combinations along with mycobacterial extracts. Note that sixteen different TB vaccine candidates are in clinical trials globally and many more are in pre-clinical development. These vaccines aim to prevent infection (pre-exposure) or prevent primary progression or reactivation of latent TB infection (post-exposure), all of which have a critical role to play in India’s big fight against TB!
So, what hope do ICMR’s two new vaccines offer to the common man?
First, you need to know the names of the two new TB vaccines: Immuvac manufactured by Cadila Pharmaceuticals and VPM 1002 manufactured by Institute of India, Pune.
Second, let’s understand the three testing phases of these trials. The trials are likely to undergo three testing phases. In the first phase, a small group of individuals take the trial vaccine, in the second phase, it is given to those with characteristics that seem similar to those for whom this new vaccine is intended. In the last phase, it is administered to several thousands of individuals, thus tested for safety as well as efficacy.
Based on the results, recommendations are to be sent to the Union Ministry of Health and Family Welfare. Though the vaccines are manufactured by Indian pharmaceutical companies, the price of the vaccines will be set by the government.