Hepatitis C: cost of illness and considerations for the economic evaluation of antiviral therapies.

Chronic hepatitis C virus (HCV) infection affects 170 million individuals worldwide. As it is detected incidentally through the evaluation of liver function tests or at the time of blood donor testing, it is usually clinically silent until the advanced stages of liver disease have occurred, when treatment is less effective and shortages of donor liver organs limit the therapeutic options. Combination therapy with ribavirin and pegylated interferon has resulted in sustained viral negative response rates of 54-61%. Because treatment is expensive and not uniformly effective, and because not all chronically infected patients will develop complications, concerns have arisen regarding the cost effectiveness of combination therapy. This paper reviews the public health and individual implications of HCV infections. Because of the latency of infection, numerous country-specific population analyses suggest that HCV will cause an increasing number of liver-related deaths over the next 10 years, despite the dramatic drop in incidence over the past 10-15 years. These deaths will be related to prevalent HCV infection from transfusion and injection drug use prior to identification of the virus and availability of screening tests in the late 1980s and early 1990s. HCV can reduce life expectancy and impair quality of life, yet not all patients will develop progressive liver disease, and antiviral treatment may have associated adverse effects. Finally, to assess the value of antiviral drugs for HCV infection, this paper reviews studies examining the costs of antiviral drugs and of the disease itself along with response to antiviral therapy and the cost effectiveness of antiviral therapy. Although antiviral therapy appears to be expensive, when also considering the likelihood of sustained viral response to therapy, and the cost savings, quality-of-life improvement and prolongation of life expectancy from the prevention of HCV complications, antiviral treatment for HCV appears to be cost effective when compared with other well accepted medical interventions.