The study includes Screening, a Qualification Phase consisting of a Naloxone Challenge and Drug Discrimination crossover study, a Treatment Phase and Follow-up. Following successful completion of the Qualification Phase the participants will be enrolled in the Treatment phase. The Treatment Phase is a randomized, double-blind, double dummy, placebo- and active controlled, 6 treatment, 10-sequence, 6 period crossover, single-dose, Williams square design study in healthy male and/or female adult, non drug-dependent recreational users. On Day 1 of each of the Treatment Phase 6 periods, which will be separated by a washout of at least 14 days, participants will receive an oral dose of either gabapentin 600 mg or 1200 mg alone, or concomitantly with a 20 mg dose of oxycodone HCl or 20 mg monotherapy of oxycodone HCl or a placebo. Study treatments will be administered under fasted conditions (overnight fast and no food until 4 hours after dosing). Water will be allowed without restriction until 1 hour prior to dosing and 1 hour after dosing.
This will be a randomized, double-blind, double-dummy, placebo- and active-controlled, 6 treatment, 6-period crossover single-dose, Williams square design study in healthy male and/or female adult, non-drug-dependent recreational opioid users.