Chronic Hepatitis B Overview
Hepatitis B, an infectious disease caused by the hepatitis B virus (“HBV”), affects the liver and occurs in both acute and chronic modalities. Patients who test positive for HBsAg, an HBV surface protein antigen, for more than six months are said to be chronic and are at risk of developing liver disease. The virus is transmitted by exposure to infectious blood or bodily fluid but is preventable by vaccination.
Currently there are about 350 million chronic HBV patients worldwide and 786,000 reported HBV-related deaths in 2010. The United States is the largest individual market with the highest absolute growth rate of HBV patients at around 15.4% through 2033 and around 9% growth in much of Europe.
Individuals with chronic hepatitis B are significantly more prone to developing cirrhosis of the liver and liver cancer. 20%-30% of all chronic hepatitis B patients develop these complications, and individuals with chronic hepatitis B are 100 times more likely to develop liver cancer than non-infected individuals. The limited efficacy of treatments for liver cancer and low survival rate (15%) mean that any treatment targeted at suppressing HBV replication before these complications arise is important to increase longevity.