Dysgeusia (alteration of taste) was an adverse event reported at an increased frequency in subjects receiving VICTRELIS in combination with peginterferon alfa and ribavirin compared with subjects receiving peginterferon alfa and ribavirin alone. Adverse events such as dry mouth, nausea,vomiting and diarrhea were also reported at an increased frequency in subjects receiving VICTRELIS in combination with peginterferon alfa and ribavirin. The proportion of subjects with decreased neutrophil and platelet counts was higher in the VICTRELIS containing arms compared to subjects receiving PegIntron/REBETOL alone

VICTRELIS® (boceprevir) is indicated for the treatment of chronic hepatitis C genotype 1 infection, in combination with peginterferon alfa and ribavirin, in adult patients (18 years and older) with compensated liver disease, including cirrhosis, who are previously untreated or who have failed previous interferon and ribavirin therapy. The following points should be considered when initiating VICTRELIS for treatment of chronic hepatitis C infection: • VICTRELIS must not be used as monotherapy and should only be used in combination with peginterferon alfa and ribavirin. • VICTRELIS efficacy has not been studied in patients who have previously failed therapy with a treatment regimen that includes VICTRELIS or other HCV NS3/4A protease inhibitors. • VICTRELIS in combination with peginterferon alfa and ribavirin has not been studied in patients documented to be historical null responders (less than a 2-log10 HCV-RNA decline by treatment week 12) during prior therapy with peginterferon alfa and ribavirin. The clinical studies included subjects who were • poorly interferon responsive. Subjects with less than 0.5- log10 HCV-RNA decline in viral load at Treatment Week 4 with peginterferon alfa plus ribavirin alone are predicted to have a null response (less than 2-log10 viral load decline at Treatment Week 12) to peginterferon alfa and ribavirin therapy [see Clinical Studies (13)]. Poorly interferon responsive patients who were treated with VICTRELIS in combination with peginterferon alfa and ribavirin have a lower likelihood of achieving a sustained virologic response (SVR), and a higher rate of detection of resistance-associated substitutions upon treatment failure, compared to patients with a greater response to peginterferon alfa and ribavirin.