Simeprevir response

NOTE: ARCHIVED ON 15 JULY 2020 BECAUSE SIMEPREVIR IS NO LONGER LICENSED FOR USE IN THE USA. THIS SUMMARY IS FOR HISTORIAL REFERENCE ONLY AND WILL NOT BE UPDATED. Simeprevir is a hepatitis C virus (HCV) protease inhibitor used in combination with other drugs to treat chronic hepatitis genotype 1 or 4 infection. Previously, the standard care of patients with HCV infection was peginterferon alfa and ribavirin, but ~40-50% of patients with HCV genotype 1 infection had a suboptimal sustained virological response (SVR). A SVR is defined as undetectable HCV RNA by the end of treatment and at a specific number of weeks after the end of treatment. The addition of simeprevir increased the SVR in patients with HCV genotype 1 infection who were previously untreated. However, there were reports of treatment failure, most commonly in adults, who failed to respond to previous peginterferon and ribavirin treatment. The FDA-approved drug label for simeprevir contains information regarding a genetic variant near the IFNL3 gene (a C to T change; rs12979860), which is a strong predictor of response to peginterferon alfa and ribavirin treatment. The label states that in phase 3 clinical trials, SVR rates were lower in patients with CT and TT genotypes, compared to patients with the CC genotype. However, patients of all IFNL3 genotypes had highest SVR rates when being treated with regimens that included simeprevir. In addition, the label strongly recommends patients with HCV genotype 1a infection should be screened for the presence of virus with the S3 Q80K polymorphism. If Q80K is detected, the label strongly recommends that alternative therapy be considered.

Medical Genetics Summaries