Liverpool HEP Interactions

Based on drug interaction studies conducted with Epclusa, no clinically significant drug interactions have been observed with atazanavir/ritonavir. Coadministration of atazanavir/ritonavir (300/100 mg once daily with emtricitabine and tenofovir-DF) and sofosbuvir/velpatasvir (400/100 mg once daily) was studied in 24 subjects. Cmax and AUC of sofosbuvir increased by 12% and 22%; Cmax, AUC and Cmin of GS-331007 increased by 21%, 32% and 42% respectively. Velpatasvir Cmax, AUC and Cmin increased by 55%, 142%, and 301%. Atazanavir Cmax, AUC and Cmin increased by 9%, 20% and 39%, respectively; ritonavir Cmax and AUC decreased by 11% and 3%, but Cmin increased by 29%.

Epclusa Prescribing Information, Gilead Science Inc., June 2021.

Coadministration of sofosbuvir/velpatasvir (400/100 mg, once daily) with atazanavir/ritonavir (300/100 mg once daily, with emtricitabine and tenofovir-DF) was studied in 24 healthy volunteers in a cross-over study. Sofosbuvir AUC and Cmax increased by 22% and 12%; AUC, Cmax and Cmin of GS-331007 increased by 32%, 21% and 42%, respectively. Velpatasvir AUC, Cmax and Cmin increased by 142%, 55% and 301%, respectively. Atazanavir AUC, Cmax and Cmin increased by 20%, 9% and 39%, respectively. Ritonavir AUC and Cmax decreased by 3% and 11%, but Cmin increased by 29%. Sofosbuvir/velpatasvir and atazanavir/ritonavir-containing regimens may be coadministered without dose adjustment.

Drug-drug interaction studies between Hepatitis C Virus antivirals sofosbuvir/velpatasvir and boosted and unboosted Human Immunodeficiency Virus antiretroviral regimens in healthy volunteers. Mogalian E, Stamm L, Osinusi A, et al. Clin Infect Dis, 2018, 67(6): 934-940.