Hepatitis C genotype 4: A report on resistance-associated substitutions in NS3, NS5A, and NS5B genes.

Treatment response in Hepatitis C virus (HCV) has generated varied effects in patients. Recently, nonresponsive and relapse patients related to host and genotype variabilities have been reported in clinical trials. However, these trials included minimal sample sizes of patients with genotype 4, the most prevalent genotype in Egypt and the Middle East, compared with genotypes 1 and 2. The genetic variabilities that have been detected within the HCV genes, especially the ones associated with genotype 4, and are linked to treatment response, will be the focus of this review with emphasis on direct acting antiviral agents. In addition, the major studies and clinical trials performed globally and their inclusivity of genotype 4 are reported. This review also delineates future study areas and missing data that need further investigation when it comes to genotype 4.