The approval has sent a clear message to BMS' peers with a host of clinical data suggesting that its drug is significantly more successful on patient management of the virus than GlaxoSmithKline's lamivudine, Novartis' telbivudine, or Gilead Sciences' Hepsera.
All four drugs are nucleoside analogues, which disrupt the enzyme that reproduces the HBV virus.
Chronic hepatitis B is not only a preventable but also a treatable disease, demonstrated by this spate of new therapeutic options available in 2006 There are currently 5 Food and Drug Administration (FDA) approved therapies for the treatment of chronic HBV.
Baraclude has already received FDA approval in March last year and has also been launched in Australia, China, Indonesia, Philippines and Singapore this year.
The drug is an oral antiviral therapy specifically designed to block the replication of hepatitis B virus (HBV). The drug is expected to be available in some countries in the European Union, the Middle East and Africa beginning in the third quarter of 2006.
"Baraclude specifically targets the viral polymerase enzyme that is responsible for replicating hepatitis B DNA," said Richard Colonno, Vice President, Infectious Disease Drug Discovery, BMS, who was speaking at the 12th International Symposium on Viral Hepatitis and Liver Disease held in Paris, Palais des Congrès, July 1-5, 2006.
"The drug substitutes for the natural substrate utilised by the viral polymerase and thus incorporation of entecavir terminates synthesis of viral DNA and interrupts the production of new hepatitis B viruses."
Chronic HBV infection is a potentially life-threatening disease and is a serious global public health issue. More than 2bn people worldwide have been infected by the virus and about 400m people worldwide have chronic hepatitis B. In Europe, an estimated 1 million people are infected with hepatitis B each year.
Hepatitis B is the 10th leading cause of death worldwide, causing 1.2m deaths annually, and chronic hepatitis B infection is the Number 1 cause of hepatocellular carcinoma, a form of liver cancer. The HBV is 100 times more infectious than HIV, the virus that causes AIDS.
Measuring the amount of the HBV in a person's bloodstream - also known as the viral load - can be an important way to predict a person's progression to serious liver disease and liver cancer.
Recent studies have shown that among hepatitis B patients who have the highest viral load levels, there is a significantly increased future risk of eventually developing cirrhosis and liver cancer.
"Hepatitis B is a serious disease and it is important for patients and physicians to have potent treatments with good tolerability," said Michael Manns, Professor, Chairman and Director, Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany.
"With the approval of Baraclude, we have an important new medication to treat chronic hepatitis B and lower patients' viral load to undetectable levels."
The benefits seen in studies of Baraclude relate to its ability to slow the progression of chronic HBV infection. This was shown in three clinical studies in patients naive to previous antiviral treatment and in patients with resistance to lamivudine, another anti-hepatitis B agent, infected by wild type virus (HBeAg positive), pre-core mutant virus (HBeAg negative) and with compensated liver disease.
After 48 weeks of treatment - or two years for those with only a virological response initially - patients receiving Baraclude achieved greater or similar responses compared to patients receiving lamivudine, with regard to improvement in the liver inflammation and degree of liver fibrosis (scarring) caused by HBV, reduction in the amount of virus in the blood, normalisation of liver function and seroconversion.
Among nucleoside-naive patients without evidence of lamivudine resistance at baseline, no resistance has emerged through 96 weeks of treatment with Baraclude. Furthermore, Baraclude was well-tolerated, similar to lamivudine.
Baraclude has a favourable benefit-risk profile based on the efficacy, resistance and safety data from clinical studies, supporting its use in the treatment of chronic hepatitis B infection in adults.