Study to Evaluate the Subjective Effects of PTI-801 in Non-Physically Dependent Subjects With a History of Drug Abuse
Condition: Opioid-Related Disorders
MeSH terms: Substance-Related Disorders; Opioid-Related Disorders
Study type: Interventional
Phase: Phase 2

Summary: 
      This is a single-center, randomized, 7-way crossover, double-blind, active and
      placebo-controlled study to evaluate the subjective effects of oxycodone combined with
      ultra-low dose naltrexone in comparison to oxycodone alone in non-physically dependent
      subjects with a history of opioid abuse. Approximately 14 subjects will be randomized to one
      of fourteen sequences selected from a balanced 7x7 Latin square design and its mirror image.
    

Detailed description: 
      At the conclusion of a screening period, qualifying subjects with a negative urine drug
      screen and ethanol breath test will be admitted to an inpatient research unit. After a 24
      hour observation period confirming that the subject is not undergoing opioid withdrawal,
      subjects will randomly receive either 30 mg oxycodone or matching placebo over two
      consecutive days in a double-blind fashion. The purpose of this oxycodone vs. placebo
      qualifying period is to select for subjects with a positive drug liking response and to
      orient subjects to the various scales. Only subjects with a positive response on the visual
      analog "Liking" scale of at least 20 points higher on active oxycodone vs. placebo will be
      eligible to continue in the double-blind 7-way crossover study. Fourteen subjects will be
      randomized to one of fourteen sequences.

      Each subject will receive a single dose of one of the following 7 treatments:

      Placebo, oxycodone 20 mg, oxycodone 40 mg, oxycodone 20 mg/naltrexone 0.001 mg, oxycodone 40
      mg/naltrexone 0.001 mg,oxycodone 20 mg/naltrexone 0.0001 mg, oxycodone 40 mg/naltrexone
      0.0001 mg.

      Oxycodone and naltrexone will be formulated in combination as a single tablet. All tablets
      will be identical in appearance. The identity of each treatment will be unknown to all study
      personnel and subjects.

      Immediately prior to and at specified time points after administration of a single dose of
      study drug, subjects will complete the following subjective scales: visual analog scales
      (VAS) for any drug effect, high, good effects, bad effects, liking, and sick; and adjective
      ratings (agonist and antagonist scales). Subjects will also be asked to complete a money
      versus drug questionnaire at various time points after drug administration. Observers will
      complete an adjective rating scale. Safety will be monitored by vital signs (heart rate,
      blood pressure, respiratory rate, and pulse oximetry), adverse events assessments, clinical
      laboratory tests, physical examinations and electrocardiograms (ECGs). In addition, pupil
      diameter (measured by photographs) will be obtained to monitor for physiological signs of
      opioid effects.

      The first double-blind dose of study drug will be administered at least 24 hours after the
      last dose of the two day qualifying period. Dosings will be separated by a washout period of
      at least 120 hours (see sample calendar in Section 6.5). The observation period for safety
      will continue for 24 hours following the final dose of study drug.
    

Intervention name(s): oxycodone and naltrexone
Intervention type(s): Drug
Intervention description(s): tablets containing 20 mg or 40 mg oxycodone
/ tablets containing 20 mg or 40 mg oxycodone combined w/0.001 mg or 0.0001 mg naltrexone
Intervention MeSH terms: Naltrexone; Oxycodone
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Treatment
Keywords: Non-physically dependent subjects; history of opioid abuse