Protease inhibitors for hepatitis C: economic implications

Chronic hepatitis C virus (HCV) infection, a blood-borne virus, is the leading cause of chronic liver disease and liver transplantation worldwide. Chronic HCV infection is usually asymptomatic in the early stages of the disease, making an estimation of the total population affected difficult to elicit. The gold standard treatment option to date has been a combination of pegylated interferon and ribavirin. Recent developments have led to the introduction of two protease inhibitors for use in chronic HCV-boceprevir and telaprevir. Phase III studies have shown both agents have the potential to significantly increase the probability of attaining a sustained virologic response (the primary outcome of interest in chronic HCV) in genotype 1 infections. However, the added cost of these agents also presents the need for decision makers to determine their place on drug formularies. The protease inhibitors are to be administered as triple therapy with the existing gold standard. However, significant variation exists as to the proposed duration of triple therapy, use of lead-in pegylated interferon and ribavirin and subsequent pegylated interferon therapy after finishing the course of triple therapy. Treatment algorithms also exist for the use of stopping rules in the case of early non-responders.The aim of this review is to highlight the current understanding of the economic impact protease inhibitors may have on health care systems and considerations required in the treatment of HCV. Economic and health-related quality of life issues are addressed from multiple viewpoints. The major aspects of the economic evaluations, to date, that included triple therapy as an alternative in the treatment of chronic HCV are brought to light. Future economic evaluations in alternative settings would be useful. The review also emphasizes the challenges for future research. This includes the potential for new therapies to no longer require inclusion of pegylated interferon and/or ribavirin, as well as the use of protease inhibitors in non-genotype 1 patients or those with significant co-morbidities such as HIV/AIDS.