New Opioid-Like drug put to the test: will it be less addictive?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Key Inclusion Criteria: * Experienced opioid user who meets the following criteria: (1) has used opioids for nontherapeutic purposes (i.e., for psychoactive effects) on at least 10 occasions in the year prior to Screening; (2) has used opioids at least once in the 12 weeks prior to Screening; and (3) self-reported intranasal use of drugs of abuse on at least 3 occasions in the year prior to Screening. * Subjects must be in good health as determined by medical history, physical examination, 12-lead ECG and vital signs measures (pulse rate, systolic and diastolic blood pressure, respiratory rate and oxygen saturation using pulse oximetry) at Screening. * Subjects must be willing to comply with the requirements and restrictions of the study. Key Exclusion Criteria: * Drug or alcohol dependence in the 12 months prior to Screening (except nicotine), as defined by the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR), or any self-reported dependence or "addiction" within the subject's lifetime (except nicotine or caffeine). * Subjects who have ever been in treatment for substance use disorder(s) (except smoking cessation). * History or presence of any clinically significant cardiac, psychiatric, endocrine, hematologic, hepatic, immunologic, metabolic, urologic, pulmonary, neurologic, dermatologic, renal or other disease at Screening, which, in the opinion of the investigator, would jeopardize the safety of the subject or the validity of the study results. * Clinically significant abnormalities in the intranasal cavity (including a deviated septum, perforated nasal septum, rhinorrhea, or excessive sneezing) or any condition that, in the opinion of the investigator, would interfere with the study procedures, data integrity or would compromise the safety of the subject. Subjects with nasal piercings/nose rings will be required to remove them for the duration of their inpatient stay.