Single-dose pharmacokinetics of amprenavir coadministered with grapefruit juice.

In this crossover study in 12 healthy volunteers, coadministration of amprenavir (1,200 mg; single dose) with grapefruit juice slightly reduced the maximum concentration of drug in serum (Cmax) compared to administration with water (7.11 versus 9.10 microg/ml), slightly increased the time to Cmax (1.13 versus 0.75 h), and did not affect the area under the concentration-time curve from 0 to 12 h (AUC(0-12)), the AUC(0-infinity), or the concentration at 12 h. Therefore, grapefruit juice does not clinically significantly affect amprenavir pharmacokinetics.

A comparison of the steady-state pharmacokinetics and safety of abacavir, lamivudine, and zidovudine taken as a triple combination tablet and as abacavir plus a lamivudine-zidovudine double combination tablet by HIV-1-infected adults.

STUDY OBJECTIVE: To investigate the steady-state pharmacokinetics of a triple combination tablet containing abacavir (ABC) 300 mg, lamivudine (3TC) 150 mg, and zidovudine (ZDV) 300 mg taken twice/day, and those of ABC 300 mg twice/day plus a double combination tablet containing 3TC 150 mg and ZDV 300 mg twice/day (ABC-COM). DESIGN: Open-label, crossover study. SETTING: Two hospital-based clinical research units. PATIENTS: Twelve men infected with human immunodeficiency virus-1. INTERVENTION: Steady-state pharmacokinetics of ABC, 3TC, and ZDV were assessed after dosing with ABC-COM and the triple combination tablet. MEASUREMENTS AND MAIN RESULTS: Steady-state pharmacokinetics of ABC, 3TC, and ZDV were similar for the triple combination tablet versus ABC-COM for the following: geometric mean (GM) area under the serum concentration-time curve, ABC 6.08 versus 5.87, 3TC 5.51 versus 5.53, and ZDV 1.38 versus 1.46 microg x hr/ml; GM maximum serum concentration (Cmax-ss), ABC 3.09 versus 3.19, 3TC 1.26 versus 1.40, and ZDV 1.19 versus 1.15 microg/ml; median time to Cmax-ss, ABC 0.75 versus 0.75, 3TC 1.50 versus 1.24, and ZDV 0.75 versus 0.75 hours; and GM oral clearance, ABC 51 versus 49, 3TC 27 versus 27, and ZDV 217 versus 206 L/hour. The GM half-lives of ABC and ZDV were similar for both treatments, 1.69 versus 1.58 and 2.30 versus 2.08 hours, respectively. CONCLUSION: Steady-state pharmacokinetics of ABC, 3TC, and ZDV were similar in patients who took them as ABC-COM or as a triple combination tablet.