[83-85] IFNβ is a natural non-pegylated agent that is administered three or more times per week either by intravenous injection or infusion. IFNβ binds to the same type I IFN receptors as IFNα and exhibits the same antiviral effect, but with a different adverse reaction profile. It is recommended for patients affected by depression who are considered unsuitable for IFNα. In a meta-analysis (n = 837) of randomized clinical controlled trials conducted overseas in 1993, the

IFN therapy group had an HBeAg negative conversion rate of 33% and an HBV DNA negative conversion rate of 37%. The corresponding rates for the untreated group were 12% and 17% respectively. These findings demonstrate the benefit of IFN therapy.[86] AZD8055 manufacturer Negative conversion for HBsAg was also higher at 7.8% for the IFN group compared to 1.8% for the untreated group. Sustained ongoing HBeAg seroconversion was observed in almost 90% of Navitoclax mw cases, as well as delayed seroconversion (occurring one or two years after the conclusion of therapy) in 10%–15% of cases.[87-89] Thus, in cases where IFN therapy in HBeAg positive patients successfully bring about HBeAg seroconversion, there is an ongoing effect that acts to hinder progression to cirrhosis and HCC, and the prognosis is therefore much improved.[90] Reports from Asia however suggest that the effect is not sustained

in the long term, with negative conversion of HBsAg being relatively rare.[87, 90] This may be attributable to host-specific factors such as race as well as genotype, infection period, and route of infection. Collation of 24 studies of therapeutic outcomes in HBeAg positive patients with chronic hepatitis B in Japan[91] yielded HBeAg negative conversion rates of 29% after one year of IFN therapy and 55% after two years, and HBeAg seroconversion rates of 12% after one year and 29% after two years. These figures are higher than the corresponding natural conversion rates of 10% and 5% respectively, indicating the efficacy of IFN therapy. However, there have

also been reports of cases that revert to HBeAg positive status after completion of treatment, and hepatitis fails to subside. It should be noted that at the time these studies were conducted, most IFN MCE therapy regimens in Japan lasted only four weeks. With a longer IFN treatment regimen, the HBeAg negative conversion rate six months after the completion of the therapy is considerably higher at 29%.[91] Japanese national medical insurance does not cover conventional IFN therapeutic agents for the treatment of HBeAg negative chronic hepatitis B. Overseas studies, mainly from Europe, report impressive biochemical and virological therapeutic benefit rates of 60%–90% in HBeAg negative patients following IFN therapy.