Disposition of amodiaquine and desethylamodiaquine in HIV-infected Nigerian subjects on nevirapine-containing antiretroviral therapy

Artesunate plus amodiaquine is used for malaria treatment in regions with overlapping HIV endemicity. Co-administration of artesunate/amodiaquine with antiretroviral therapy (ART) may result in drugdrug interactions, but minimal data exist. This study evaluated the impact of nevirapine-based ART, containing a backbone of zidovudine and lamivudine, on the disposition of amodiaquine and its active metabolite, desethylamodiaquine (DEAQ). This was an open-label, parallel-group pharmacokinetic comparison between HIV-infected, adult subjects receiving steady-state nevirapine-based ART (n10) and ART-naive subjects (control group, n11). All subjects received a loose formulation of artesunate/amodiaquine (200/600 mg) daily for 3 days, with serial pharmacokinetic sampling over 96 h following the final dose of artesunate/amodiaquine. Amodiaquine and DEAQ were quantified using a validated HPLC method with UV detection. Pharmacokinetic parameters were determined using standard non-compartmental methods. Exposures to both amodiaquine and DEAQ were significantly lower in the nevirapine-based ART group compared with the control group (amodiaquine AUC(024) 145 versus 204 ngh/mL, P0.02; DEAQ AUC(096) 14571 versus 21648 ngh/mL, P0.01). The AUC(DEAQ)/AUC(amodiaquine) ratio was not different between groups (ART group 116 versus control group 102, P0.67). Subjects on nevirapine-based ART had lower exposure to both amodiaquine and DEAQ (28.9 and 32.7, respectively). Consequently, this may negatively impact the effectiveness of artesunate/amodiaquine in HIV-infected individuals on this ART combination.