IFNL4 Genotype Frequencies in Asian Populations Support Shorter Duration Therapy with Sofosbuvir-Based Hepatitis C Virus Regimens to Increase the Number Cured.

Globally, ∼56.8 million people are chronically infected with hepatitis C virus (HCV), with about half residing in Asia. The cost and efficiency of delivering regimens based on direct-acting antiviral agents for HCV are important considerations in implementing these curative treatments. For sofosbuvir-based regimens, most patients are treated for 12 weeks; however, treatment for 8 weeks has been shown to cure HCV infection in 95% of patients without cirrhosis. Furthermore, virological failure after 8-week treatment occurs in only 1%-2% of individuals without cirrhosis, who have a favorable IFNL4 genotype, which is present in >50% of South Asians and >80% of East Asians. We propose that sofosbuvir-based treatment for 8 weeks, or perhaps shorter, would yield high response rate regimens in Asian countries and markedly increase the number of patients who could be cured for a given cost of the medication. We propose that a noninferiority trial in an East Asian population be conducted to test this hypothesis.