The All India Institute for Medical Sciences (AIIMS) pathology department is working upon a nano technology platform for oral vaccine for Hepatitis B. For the past three years, researchers at AIIMS have conducted a series of trials on mice and guinea pigs. They were fed orally and results were effective. In the nano technology platform, polymeric particles 60 nano meter was loaded with Hepatitis B protein antigen on mice.
The oral vaccine is likely to be in the market in the next three years or so after the human trials are successful on the lines of World Health Organisation (WHO) guidelines. Once this oral vaccine comes in the market, India will be the first country in the world to provide safe, cost effective and non-invasive method suitable for mass vaccination.
Professor of Pathology at the AIIMS Dr Amit K Dinda said, “We have made the spherical particle into nano size with 60 nano meters from a polymer which totally bio compatible (poly carprolactone). This polymer degrades very slowly inside the body and safe polymer for the human body. Initial hypothesis was, if we can load the antigen in this polymeric nano sphere and put inside the body this will be taken by antigen presenting cell. It can slowly reveal the antigen for long time with generation of effective prolonged immune responses.”
“Normally, after giving up injection for H-B, we need to give booster dose. Here, only in a single application over four months plus. We have administrated in mouse model, after giving orally directly absorbed through intestine and goes through lymphoid nodes which is very important for vaccination.”
Currently, the vaccine for H-B is available in the market has got lot of side effects. Researchers compared the results of oral vaccine with that of Alum- based formulation like Shanvac-B vaccine available in the market. Dr Dina said two groups of mice which were given oral dose were responding well and other group of mice which was given Shanvac-B vaccine started to lose their immunity after two weeks. “This second group of mice needed booster dose.”
The major advantage would be that the vaccine is oral dose. No booster dose needed after this oral vaccination, he said. Two months in mice is equivalent to nine to 10 years in human beings, Dr Dinda said.
Dr Dinda said in a rural vaccination programme for the developing countries like India, the dropout rates for the booster doses is very high defeating the purpose of mass immunisation. “The current efficacy of the nanocarrier system for efficient antigen presentation disseminated in peripheral lymphoid tissues following administration with a prolonged antibody response, which can minimise the requirement of booster dose” adding that this whole development of the oral H-B vaccine is published in Journal by Elsevier ‘Vaccine.’
Hepatitis B, a viral infection affects the liver and cause lifelong liver related disorder leading to cancer. India has over 40 million Hepatitis B infected patients, second only to China.
WHO statistics said two to five per cent of India’s population may be affected by this virus. Each year, one lakh patients die of viral Hepatitis (including Hepatitis B and C) in the country. Researchers hope to launch oral vaccine for other infectious diseases such as Tuberculosis after the novel nanocarrier for oral Hepatitis B vaccine is launched. It may be noted that whole research work was conducted at AIIMS laboratory and was funded by the bio technology department.