Coadministration had no significant effect on dolutegravir exposure (AUC increased by 1%, Cmax and Ctrough decreased by 3% and 8%). There was no effect on tenofovir exposure. No dosage adjustment is necessary.

Tivicay Summary of Product Characteristics, ViiV Healthcare, March 2019.  

 

Based on drug interaction trial results, tenofovir can be coadministered with dolutegravir without a dose adjustment. Coadministration of tenofovir-DF (300 mg once daily) and dolutegravir (50 mg once daily) was studied in 15 subjects. Dolutegravir Cmax and Ctrough decreased by 3% and 8%, and AUC increased by 1%. Tenofovir Cmax, AUC and Ctrough increased by 9%, 12% and 19%, respectively.

 

Coadministration of dolutegravir (50 mg once daily) and tenofovir-DF (300 mg once daily) was studied in 15 HIV-negative subjects. The pharmacokinetic parameters of tenofovir and dolutegravir when coadministered were comparable to those when given alone, demonstrating no significant drug interaction. Dolutegravir AUC increased by 1%, but Cmax and Ctrough decreased by 3% and 8%, respectively. Tenofovir AUC, Cmax and Ctrough increased by 12%, 9% and 19%, respectively.