Hepatitis B is a virus, which infects the liver of humans and other primates. It is spread by contaminated blood or other bodily fluids. Infection can be either acute (short term rapid onset) or chronic (a longer-term persistent infection). Acute symptoms are liver inflammation, vomiting, jaundice and occasionally, death. Chronic infections can result in liver cirrhosis and liver cancer.
In 2004 it was estimated that 350 million people were infected with the disease. The prevalence rates range from over 10% in areas of Asia and Africa, to less than 0.5% in Europe and North America. About one third of the world’s population have been infected with Hepatitis B.
The first vaccine against Hepatitis B was produced in 1981. Current vaccines are based on a protein purified from the virus coat, produced in cultured yeast or mammalian cells. This makes it relatively expensive. The recommended vaccine regime involves 3 vaccinations, the second one month after the first and the final 6 months after the second. The relatively high cost of the vaccine, combined with the lengthy treatment schedule make, the vaccine impractical to use in many countries where it is most needed. Additionally, even three doses of the vaccine only give protection in 95% of people.
BigDNA’s primary vaccine candidate is a Hepatitis B vaccine, based on our novel patented bacteriophage delivery technology. In preliminary pre-clinical trials, our vaccine gave responses, which were significantly better than those produced by a commercially available protein vaccine. This data indicates that we may get a protective immune response after 1 or 2 vaccinations. This increased immune response, potentially reduced number of immunisations, combined with the cheapness and ease of production result in a vaccine product with large potential markets in both developed and developing countries.