Yes, testing for NS5A RAVs at positions 28, 30, 31, and 93 is recommended prior to initiation of Zepatier® therapy for patients with HCV genotype 1a.6,9 In addition, NS5A testing prior to initiation of daclatasvir plus sofosbuvir therapy should be considered for patients with genotype 1a and cirrhosis.5
Naturally occurring NS5A RAVs conferring moderate to high levels of resistance have been found at a low prevalence in HCV genotype 1a and 1b patients.10,11 However, the impact of these baseline variants on treatment efficacy with combination DAA regimens in other circumstances may be limited and further studies are warranted.3,4,12
The AASLDand IDSAguidelines suggest consultation with an expert in the treatment of HCV infection if uncertainty remains regarding the applicability of NS5A RAV testing.9