BASEL, Switzerland -- The first study reporting on the use of PEGASYS (peginterferon alfa-2a) for the treatment of chronic hepatitis B virus (HBV) was published today in the Journal of Viral Hepatitis (1). The study found that PEGASYS is superior in efficacy to conventional interferon, the initial therapy recommended by a recent International Consensus Conference (2).
The 194 patients in the Phase II study were treated with either conventional interferon three times weekly or PEGASYS (at 90 micrograms, 180 micrograms or 270 micrograms) once weekly for a 24-week-period, and were then observed with no further treatment for another 24 weeks. The study assessed what is referred to as the 'combined response' of patients. This response includes the loss of viral protein, suppression of HBV DNA levels and the normalisation of the liver's function, all strong indicators of treatment efficacy.
Overall, 28 percent of patients who received PEGASYS for six months at the180 (g dose achieved a 'combined response.' In sharp contrast, only 12 percent of patients who received conventional interferon achieved a combined response.
"The viral reduction achieved with PEGASYS is substantially more pronounced than what's achieved with conventional interferon. It appears that PEGASYS enhances the patient's immune response against the virus as well as profoundly inhibiting the virus," said Prof. Graham Cooksley, the author of the study and senior principal research fellow, Clinical Research Centre, Royal Brisbane Hospital, Australia. "One reason this study was undertaken was because of the short-comings with current therapies, including nucleoside analogues, which offer less than optimal efficacy, often require long-term or continuous administration and have been associated with drug resistance."
In the paper, the authors note that the beneficial effects of PEGASYS were also observed in difficult to treat patients, for example those with cirrhosis, those with low ALT or high HBV DNA levels at baseline, and those with HBV genotype C. The rapid and sustained reductions in HBeAg and HBV DNA levels indicated that PEGASYS has a more profound impact on HBV than conventional interferon alfa-2a.
The paper notes that the primary treatment goal in chronic hepatitis B remains sustained suppression of HBV replication in the absence of therapy. HBeAg loss and "e" seroconversion (antibodies against the viral antigens) are indicative that this goal has been reached. Importantly, seroconversion significantly lowers a patient's risk of developing end-stage liver disease or death. "For this reason, the documented seroconversion rate of 33 percent in six months seen in this study with peginterferon alfa-2a (40KD), an agent with both antiviral and immunomodulatory properties, is eminently promising."
Hepatitis B is a blood-born virus that attacks the liver and is the most common serious liver infection in the world. The hepatitis B virus is highly contagious and is relatively easy to transmit from one infected individual to another. It is 100 times more infectious than the HIV virus.
Despite a highly effective vaccine, more than 2 billion people have been infected by HBV and 350 million people have chronic infection, which can be easily transmitted by blood-to-blood contact, during birth, sex, and by sharing needles. HBV and HCV rank in the top four causes of cancer deaths in most countries in Asia and the Western Pacific rim. (3) For those chronically infected with HBV, treatment is the only option.
PEGASYS, a new generation hepatitis therapy that is different by design, provides significant benefit over conventional interferon therapy in patients infected with HBV and HCV.
Roche is committed to the viral hepatitis disease area, having introduced Roferon-A for hepatitis B and C, followed by PEGASYS in hepatitis C and now PEGASYS is demonstrating similar superior efficacy over conventional interferon in hepatitis B.
(i) Cooksley, W. Graham E et al. Peginterferon alfa-2a (40KD): An advance in the treatment of HBeAg-Positive Chronic Hepatitis B. J. Viral Hepatitis. 2003;10: 298-305.
(ii) EASL (European Association for the Study of the Liver) International Consensus Conference on Hepatitis B, 13-14 September 2002 Geneva, Switzerland, Consensus statement. Journal of Hepatology 38 (2003) 533-540.
(iii) Chu, CM. Natural History of Chronic Hepatitis B Virus Infection in Adults with Emphasis on the Occurrence of Cirrhosis and Hepatocellularcarcinoma. J Gastroenterol. Hepatol. 2000; 15 (suppl.):E25-30.
Source: Roche Pharmaceuticals