HCV Genotype 6a Escape from and Resistance to Velpatasvir, Pibrentasvir, and Sofosbuvir in Robust Infectious Cell Culture Models.

Strains of HCV genotype 6a isolated from patients can be adapted to propagate in cultured cells, permitting studies of the complete life cycle for this important genotype. The combination of velpatasvir and sofosbuvir is required to block propagation of original HCV genotype 6a, which quickly becomes resistant to single inhibitors via the rapid emergence and persistence of RAS. These features of HCV genotype 6a could compromise treatment.