Neither branded nor generic lopinavir/ritonavir produces adequate lopinavir concentrations at a reduced dose of 200/50 mg twice daily.

We assessed pharmacokinetic (PK) parameters of reduced dose lopinavir/ritonavir(LPV/r) and compared generic and branded tablets. Twenty HIV-infected patients using protease inhibitors with HIV RNA <50 copies per milliliter were randomized to generic or branded LPV/r 200/50mg twice daily (BID). At week 2, PK-sampling was performed. Patients crossed over to the other arm until week 12, with another PK-sampling at week 4. Subtherapeutic lopinavirconcentrations were observed in 10/40 samples. PK parameters were comparable between branded and generic tablets. All patients remained virologically suppressed at week 12. In conclusion, LPV/r 200/50mg BID does not lead to adequate lopinavirplasma concentrations. Generic and branded LPV/r have comparable PK-parameters.