Hepatitis B is caused by the hepadnaviridae virus and in many cases, HBV infection is asymptomatic and self-resolves. However, chronic infection occurs in about 5% of cases but this rises in “at risk” groups, particularly immunocompromised.  Transmission from mother to infant is high: chronic infection occurs in around 90% of cases for babies born to infected mothers. Beyond foetal transmission, other common blood-mediated infection routes in developed countries are unprotected sex and shared use of needles between drug addicts. With blood screening for the virus now in place, blood transfusion and transplantation are infrequent sources of transmission.

A protective vaccine has been available since 1982 and this has dramatically reduced the incident rate when used, with over 95% effectiveness. The US incident rate is now around 60,000 pa compared with 260,000 pa prior to the availability of a vaccine – and around 25% of these new cases are from foetal transmission. However, there remain around 1.25 million chronically infected in the US and worldwide, this rises to around 350 million people. HepB is particularly common in parts of Africa and much of Asia: worldwide an estimated 2 billion people have been infected. While prevalence is <1% in many developed countries, it is 8-16% of the population in some countries.

In chronic infection, usually arising if the virus is not cleared within six months of first infection, the virus is either replicating or non-replicating (“latent”). Typically, in time the virus will begin to replicate. In around 15-25% of chronically infected, liver damage occurs, particularly cirrhosis. Resultant liver cancer - hepatocellular carcinoma (“HCC”) – is overwhelmingly fatal, typically within months of diagnosis if untreated, with at best months of life extension with surgical and therapeutic intervention.

Early therapeutic use of hep B immunoglobulin advanced with the introduction of α INF. In around 10% of cases treated, viral eradication is achieved, but the cost of therapy is very high and response levels remains unsatisfactory, as are common side effects. Some anti-viral therapeutics successfully suppress viral replication in some patients for some time, when taken chronically and hence at a cost. Consequently the overall situation remains one of major unmet needs, to address the large number of chronically infected, facing significant life-threatening consequences.

ImmBio’s development programme provides a much-needed new approach to infection management, by efficiently stimulating the body’s own immune system for long-term suppression or eradication of the virus, including in patient groups who do not respond to other approaches. ImmBio is collaborating with the Institute of Cell & Molecular Science, Queen Mary's School of Medicine and Dentistry, The Royal London Hospital.