An open-label multicentre pilot study evaluating the pharmacokinetics (PK) of co-administered lopinavir (LPV) and nevirapine (NVP) in HIV+ adults

Methods In this prospective, 48-week (wk), multicentre study, 40 patients (39 ART-naive) were recruited to receive LPV/r SGC (533/133 mg BID) plus NVP (200 mg BID) and undergo PK sampling (0–12 hr) at wk 4 and wk 48. In one of the two participating centres, switches to the LPV/r tablet formulation (400/100 mg BID) were allowed between wk 4 and 48, once HIV-RNA was <50 copies/ml. LPV concentrations were determined by HPLC-MS/MS and NVP concentrations via HPLC-UV. PK parameters were calculated via non-compartmental analysis and within-subject changes assessed by geometric mean ratios (GMR) with 95% confidence intervals (95% CI).