CYP3A5 genotype has no impact on plasma trough concentrations of lopinavir and ritonavir in HIV-infected subjects.

CYP3A5 genotype has no impact on the trough plasma concentrations of lopinavir and ritonavir in human immunodeficiency virus (HIV)-infected individuals on stable highly active antiretroviral therapy (HAART). This is ascribed to a drug interaction, such that ritonavir by inhibiting CYP3A activity, may occlude the pharmacokinetic consequences of functional polymorphisms in the CYP3A5 gene. In the clinical setting, where lopinavir and ritonavir are always combined, CYP3A5 genotype is of no consequence on the trough plasma concentrations of these drugs.