IFNL4 Genotype for Predicting Response to Ledipasvir/Sofosbuvir

Overview

Background: Hepatitis C virus (HCV) infection is a leading cause of hepatocellular carcinoma and end-stage liver disease. Ledipasvir/sofosbuvir is used to treat chronic HCV. The drug name for it is Harvoni. It is a very effective treatment, but it is expensive. Researchers have found a genetic variation that predicts how people will respond to this treatment. They want to learn more about this genetic link. It could help develop better treatments for HCV. Objective: To study if certain inherited genetic differences and other factors affect the different ways patients respond to treatment with Harvoni. Eligibility: Adults ages 18 who are members of the Kaiser Health Plan and have recently been treated for hepatitis C with Harvoni Design: Researchers will review medical records to identify a group of people who could be in the study. Participants will provide a saliva sample at home. They will get instructions and kit to collect it in. Participants will spit into a funnel until it reaches a mark on the funnel. It will be about 1 teaspoon of saliva with no bubbles. They will return the sample in a prepaid mailer. Researchers will do genetic tests on the samples. The participant data will be kept confidential. It will not be given to insurance companies. Participants will not be given any test results. ...

Hepatitis C virus (HCV) infection is a leading cause of hepatocellular carcinoma (HCC) and end stage liver disease - successful treatment markedly reduces those risks. Ledipasvir/sofosbuvir is a highly effective, but expensive, treatment for chronic hepatitis C. Previously, we demonstrated that genetic variation in IFNL4 predicts response to this regimen. We now propose to examine the association between genotype for the functional IFNL4-DeltaG/TT polymorphism and treatment response among patients enrolled in a large managed care organization. In a two-stage design, limited demographic and clinical data for patients who have been treated with ledipasvir/sofosbuvir will be ascertained from an electronic database. In the second stage, additional demographic and clinical data will be extracted from medical records and consented patients will provide a specimen for IFNL4 genotyping. These data will be combined to examine associations of IFNL4-DeltaG/TT genotype and other variables with response to ledipasvir/sofosbuvir. We will also develop a clinical prediction model for response to ledipasvir/sofosbuvir treatment. These results could inform more efficient treatment of HCV in the United States and globally.