Recent advances in vaccination of non-responders to standard dose hepatitis B virus vaccine

Abstract

Hepatitis B virus (HBV) infection is a global health problem. It is estimated there are more than 2 billion individuals exposed to the virus and 250 million are chronically infected. Hepatitis B is the cause of more than 600000 annual deaths due to cirrhosis and hepatocellular carcinoma. An effective vaccine exists and preventative initiatives center around universal vaccination especially in those at highest risk. Effective vaccination algorithms have led to a significant decline in the development of new infections and its devastating consequences. The vaccine is administered intramuscularly in three doses, with 95% showing long lasting serologic immunity. An additional fourth dose or a repeated higher dose three course regimen is given to those that fail to show immunity. Despite these additional regimens, some remain vulnerable to hepatitis B and are deemed non-responders. Individuals with chronic disease states such as kidney disease, liver disease, diabetes mellitus, as well as those with a genetic predisposition, and those on immunomodulation therapy, have the highest likelihood of non-response. Various strategies have been developed to elicit an immune response in these individuals. These include increased vaccination dose, intradermal administration, alternative adjuvants, alternative routes of administration, co-administration with other vaccines, and other novel therapies. These alternative strategies can show improved response and lasting immunity. In summary, HBV vaccination is a major advance of modern medicine and all individuals at risk should be sought and vaccinated with subsequent adequate titers demonstrated.

Keywords: Adjuvants; Hepatitis B vaccine; Intradermal vaccine; Non-responders; Oral vaccine.