Based on drug interaction studies conducted with sofosbuvir/velpatasvir, no clinically significant drug interactions have been observed with dolutegravir. Coadministration of sofosbuvir/velpatasvir (400/100 mg, once daily) and dolutegravir (50 mg once daily) had no effect on the pharmacokinetic parameters of sofosbuvir (AUC and Cmax decreased by 8% and 12%), GS-331007 (AUC and Cmin both decreased by 1%, Cmax increased by 1%), velpatasvir (AUC, Cmax and Cmin decreased by 9%, 6% and 12%) or dolutegravir (AUC, Cmax and Cmin increased by 6%, 6% and 4%) was observed.