The Typbar TCV, a Vo-tetenus conjugate vaccine manufactured by Hyderabad-based vaccine maker Bharat Biotech Ltd is the first typhoid conjugate vaccine to get World Health Organization prequalification. Although the vaccine is approved for use in India, it is not a part of India’s Universal Immunisation Programme as yet.
The intramuscular dose of the conjugate vaccine has shown a robust immune response in infants younger than six years old unlike the earlier typhoid vaccines that could be administered to children 2 years and above. The results, published a year ago in the journal the Lancet, show that Typbar TCV is 87 per cent effective and can be given to infants over six months old. And the prequalification of the vaccine by the World Health Organization at the end of December 2017, along with the recommendation of the Strategic Advisory Group of Experts (SAGE) on immunisation shows that the vaccine meets the acceptable standards of safety, quality and efficacy.
In order to conduct the study and know the strength of the vaccine, Bharat Biotech not only did clinical trials in India but also undertook a ‘human challenge study’ in Oxford, Bharat’s founder and managing director Dr. Krishna Ella said. For the Typbar to reach vulnerable populations, Bharat Biotech has offered the vaccine at the price of $1.50 per dose for procurement for GAVI-supported countries.
For the trial, 100 healthy volunteers in Oxford, most them were medicals students, agreed to swallow the live typhoid bacteria as a part of the study. The major reason causing Typhoid is Salmonella serovar Typhi bacteria which spread largely due to contaminated water. In the most severe cases, the disease can be life threatening and in other cases, it can cause a long lasting intestinal problem. Around 12 million Typhoid cases were reported in the year 2016, which resulted in the death of 1.30 lakh people across the world. Annually, there have been 1.28 lakh deaths due to typhoid.
The disease widely impacts children and adolescents, disrupting the infant’s education and affecting the families’ economic development. It is due to this fact that this vaccine paves the way for countries to introduce it into their immunization programs. According to Ella, the company has spent over Rs 150 crore on the development and study of the vaccine. It has taken 14 years to create the conjugate vaccine, but it has finally proved to be effective. Ella and her team have created the vaccine that would protect a person from the age of 6 months to 65 years.
GAVI supplies vaccines to countries across Africa mostly. Bharat Biotech has donated 50,000 doses to Agra Khan University located in Karachi, Pakistan to vaccinate the children. This is because the population of both Karachi and its neighbour city Hyderabad is resistant to third line antibiotics, said Ella. The university will soon be acquiring an additional 3 lakh doses of the vaccine.
Ella said that India will still have to wait to acquire the vaccine from the company. However, the vaccine, priced at Rs 1500/dose, will still be expensive for the poorer patients who are more prone to the disease.