Study of the Abuse Liability of Oxycodone HCl/Niacin in Subjects With a History of Opioid Abuse

In the Treatment Phase, subjects randomly received oxycodone HCl 40 mg administered in
combination with niacin 240 mg and oxycodone HCl 40 mg alone in crossover design. 15 subjects
were randomized to receive oxycodone/niacin first followed by oxycodone with a 48 hour
washout between doses. 15 subjects randomized to receive oxycodone before the
oxycodone/naicin dose with a 48 hour washout between doses. The purpose of the Treatment
Phase was to assess the abuse liability and abuse deterrence potential of 4 times the
recommended 2-tablet dose of Acurox® Tablets 5/30 mg versus oxycodone HCl 40 mg alone (8
tablets per dose).

All 30 subjects received a single dose of each study treatment. Subjects were fasted prior to
dosing on all dose days.

Inclusion Criteria:

- Subject is male or female between 18 and 55 years of age

- Subject meets DSM-IV Criteria for the Diagnosis of Opioid Substance Abuse and subject
is unlikely to experience an idiosyncratic reaction or respiratory depression after
ingesting 40 mg of oxycodone

- Body weight is not more than 20% above or below ideal body weight

- Subject agrees to abstain from any Rx or OTC drugs (except as authorized by the
Investigator) or alcohol

- Subject is in generally good health

- Subject is reliable, willing, cooperative, able to communicate effectively, and has a
minimum of a 6th grade reading level

- Subject has an acceptable score on the MMSE for cognitive impairment

- For women of child-bearing potential: woman is not pregnant and not nursing, and is
practicing an acceptable method of birth control

Exclusion Criteria:

- Subject has a disease that may endanger the subject or the validity of the data

- Subject is currently physically dependent on opiates or alcohol

- Subject was exposed to any investigational drug within 30 days prior to the inpatient
phase

- Subject has a history of hypersensitivity to any drug, or a known allergy to any
component of the study drug formulation

- Subject has a positive urine drug screen for a non-opiate drug

- Subject has a predisposing condition that may place the subject at risk for receiving
niacin or oxycodone, or confound the study analyses

- Subject ingested niacin at doses higher than SDI within 14 days prior to the inpatient
phase

- Subject has an abnormal bleeding tendency