HCV Response-Guided Therapy: Should Treatment Length Be Shortened or Extended?

The role of interferon in the new era of hepatitis C treatments

Interferon has been the backbone of HCV treatment since this agent was first introduced nearly two decades ago. Interferon acts to eradicate HCV via two mechanisms: by directly inhibiting HCV replication via an indirect anti-viral mechanism and by modulating an immune response against hepatocytes infected with HCV. The current treatment of chronic HCV genotype 1 is the combination of peginterferon, ribavirin and a single direct acting anti-viral agent (DAA). Within the next 1-2 years multiple DAA combinations will eradicate and cure HCV at high rates without interferon. The role interferon will play in the next era of HCV treatment will depend upon balancing cost, efficacy and the development of an interferon with a more favorable adverse event profile.

Triple therapy with boceprevir or telaprevir for treatment naïve HCV patients

Boceprevir and telaprevir are the first two protease inhibitors available for the treatment of patients infected with HCV genotype 1. In treatment naïve patients, a sustained virologic response (SVR) of 70-80% is observed when either of these protease inhibitors is used with peginterferon and ribavirin A rapid virologic response (RVR) is observed in 56-60% of them allowing a shorter course of 24-28 weeks of therapy with an excellent SVR rate of 90% or even higher. Patients who do not achieve RVR, and those with cirrhosis should be treated for 48 weeks. Both drugs, boceprevir and telaprevir, achieve similar SVR rates but treatment strategies are completely different for each drug. The decision of which protease inhibitor to utilize should weigh several factors including the treatment strategy, duration of therapy, the likelihood of achieving an RVR, adverse event profile, and cost. Besides, the physician's experience with each drug and the wishes of the patient also have to be considered.

Triple therapy for HCV genotype 1 infection: telaprevir or boceprevir?

Boceprevir and telaprevir are the first two protease inhibitors available for the treatment of patients infected with hepatitis C virus (HCV) genotype 1. A sustained virological response (SVR) of 70-80% is observed when either of these protease inhibitors is utilized with pegylated interferon (PEG-IFN) and ribavirin (RBV) in treatment naïve patients. Both agents are also highly effective in patients who failed to achieve a SVR during previous treatment with PEG-IFN/RBV. A rapid virological response (RVR) is observed in 56-60% of treatment naïve patients. Patients who achieve a RVR can be treated with a shorter course of therapy (24-28 weeks) and still achieve a SVR rate of 90% or higher. Patients who do not achieve a RVR, those with cirrhosis and certain prior non-responders should be treated for 48 weeks. Although the SVR rates observed with boceprevir and telaprevir are quite similar both globally and within sub-populations, the treatment algorithms for the two agents are unique. The decision of which protease inhibitor to use should assess several factors including the treatment scheme, duration of therapy, adverse event profile, cost and the likelihood of achieving a RVR. The latter is highly dependent upon IFN sensitivity and the IL28B genotype.

Interferon-free regimens: the near future, the likely and the not so likely

Remarkable progress has been achieved in the treatment of chronic hepatitis C virus (HCV) since interferon was first used to treat this pathogen more than 20 years ago. This article reviews the mechanisms through which interferon is believed to suppress HCV and lead to SVR. These observations are used to speculate as to whether an all-oral antiviral cocktail could "cure" HCV in the near future.