- Subject is a recreational opioid user who is NOT physically dependent on opioids based
on Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision
(DSM-IV-TR) criteria, and the Naloxone Challenge. A recreational opioid user is
defined as recreationally abusing opioids for non-therapeutic purposes (i.e., for
psychoactive effects) on at least 10 occasions within the last year and at least once
in the 12 weeks prior to Visit 1.
- Subject is in generally good health as determined by medical history, physical
examination, vital signs, clinical laboratory tests, and 12-lead electrocardiogram
- Has a history or current diagnosis of substance dependence (excluding caffeine and
nicotine), as assessed by the Investigator using the DSM IV-TR criteria.
- Has participated in, is currently participating in, or is seeking treatment for
substance- and/or alcohol-related disorders (excluding nicotine and caffeine).
- History or presence of any clinically significant illness (e.g., cardiovascular,
pulmonary, hepatic, renal, hematologic, gastrointestinal, endocrine, immunologic,
dermatologic, neurologic, oncologic, musculoskeletal, or psychiatric) or any other
condition, which in the opinion of the Investigator would jeopardize the safety of the
subject or the validity of the study results.
- Has a known allergy or history of hypersensitivity to morphine sulfate, opioids in
general, naltrexone hydrochloride (HCl) or similar compounds and/or the known
excipients in the investigational drug products.
- Has any condition in which an opioid is contraindicated (e.g., significant respiratory
depression, acute or severe bronchial asthma or hypercarbia, or is suspected of having
- Females who are pregnant, lactating, or are planning to become pregnant during the
course of the study. Females with a positive serum pregnancy test at Visit 1 or at any
subsequent study visit will be excluded from participating in the study.