Pain Therapeutics Inc. announced positive results from a human abuse potential study of its late-stage drug candidate, REMOXY.  Study results indicate that in non-dependent, recreational opioid users, nasal administration of REMOXY resulted in significantly lower abuse potential compared to immediate-release (IR) oxycodone.  All study subjects reported reduced ‘Drug Liking’ ‘Take Drug Again’ and ‘Drug High’ for REMOXY compared to oxycodone IR.  In addition, nasal administration of REMOXY showed lower exposure to oxycodone, lower peak concentrations (Cmax) and longer time to peak drug concentration (Tmax) against comparator drugs, suggesting comparatively lower abuse potential.  This Category 3 nasal abuse potential study was conducted in accordance with the U.S. Food and Drug Administration’s (FDA) Guidance for Industry for Abuse-Deterrent Opioids.  In a randomized, double-blind, active- and placebo-controlled, single-dose, 4-way crossover study, 38 recreational opioid users with a history of intranasal drug abuse were enrolled in the study.  The primary endpoint was ‘Drug Liking’.  Secondary endpoints included ‘Take Drug Again’, ‘Drug High’ and pupil size.  There were four treatment arms: REMOXY 40 mg intact; REMOXY 40 mg microwaved; oxycodone IR 40 mg and placebo.  All treatments were administered nasally.  Thirty-six subjects completed the study.  In addition, the first 20 subjects who completed the double-blind portion of the study also participated in a supplemental FDA Category 2 treatment arm to measure pharmacokinetic parameters following the nasal administration of 40 mg crushed OxyContin®.