Pharmacokinetic interactions between buprenorphine/naloxone and raltegravir in subjects receiving chronic buprenorphine/naloxone treatment

Background: Interactions between human immuno-deficiency virus (HIV) and opioid-dependence therapies can occur. Objectives: We sought to determine whether such interactions occurred between buprenorphine/naloxone and raltegravir. Methods: We performed a within-subject open-labeled pharmacokinetic and pharmacodynamic study in 12 HIV-seronegative subjects stabilized on at least 3 weeks of buprenorphine/naloxone therapy. Subjects underwent baseline and steady-state evaluation of the effect of raltegravir 400 mg BID on buprenorphine/naloxone parameters. Results: Compared with baseline values, buprenorphine AUC0-24 h (58.2 vs. 56.0 hr*ng/mL) and Cmax (7.37 vs. 6.60 ng/mL) did not differ significantly after achieving steady-state raltegravir. Similar analyses of norbuprenorphine, the primary metabolite of buprenorphine, demonstrated no significant difference after raltegravir administration. Naloxone concentrations were unchanged for AUC0-24 h (.595 vs. .581 hr*ng/mL), Cmax (.251 vs. .243 ng/mL) and Tmax (.75 vs.1.08 h). Objective opioid withdrawal was not observed. The AUC0-12 h and Cmax of raltegravir did not significantly differ from historical controls (5543 vs. 4428 h*ng/mL and 1070 vs. 1266 ng/mL), respectively. Conclusion: The addition of raltegravir to stabilized patients receiving buprenorphine/naloxone does not significantly affect buprenorphine/naloxone or raltegravir pharmacokinetic or pharmacodynamic parameters. Copyrigh