Effectiveness, Safety, and Tolerability Study of Oxymorphone Immediate Release (IR) Oral Liquid in Post Surgical Pediatric Subjects

Inclusion Criteria:

1. Males or females between 2 to ≤12 years of age. Females of child-bearing potential must be practicing abstinence or using a medically acceptable form of contraception (eg, intrauterine device, hormonal birth control, or double barrier method). For the purpose of this study, all peri- and post-pubertal females will be considered to be of child-bearing potential unless they are biologically sterile or surgically sterile for more than 1 year
2. Subjects must be at least 10 kg and BMI ≤30
3. Scheduled to have a surgery for which oral opioid analgesia will be needed to manage postoperative pain for at least 24 hours (Single-Dose Phase) or 48 hours (Multiple-Dose Phase)following intraoperative and/or postoperative parenteral analgesia
4. Be hospital inpatients, expected to be hospitalized for at least 24 hours (Single-Dose Phase) and 48 hours (Multiple-Dose Phase) following the initial administration of oxymorphone immediate release
5. Available lab results, either intraoperatively (prior to surgical incision) or from within 21 days preoperatively, for clinical chemistry and hematology laboratory analytes (the results must have been reviewed by the Investigator for study eligibility)
6. Able to provide pain assessment evaluations using an age-appropriate instrument provided in the protocol
7. On an intravenous analgesic regimen utilizing a short-acting opioid analgesic following surgery AND anticipated to be switched to an oral opioid as part of the analgesic regimen (according to institution SOC)
8. Demonstrated the ability to tolerate clear fluids following surgery according to the SOC at each institution
9. Informed of the nature of the study and written informed consent has been obtained from the legally responsible parent(s)/legal guardian(s)
10. Provided assent in accordance with IRB requirements
11. Line in place for blood sampling

Exclusion Criteria:

1. Known allergies or sensitivities to oxymorphone or other opioid analgesics
2. Known sensitivity to any component of the study drug
3. Life expectancy <4 weeks
4. Positive pregnancy test at screening (females of reproductive age only)
5. Pregnant and/or lactating
6. Cyanotic heart disease
7. Respiratory, hepatic, renal, neurological, psychological disease, or any other clinically significant condition that would, in the Investigator's opinion, preclude participation in the study
8. Preoperative opioids administered for a period of more than 72 hours in duration
9. Abdominal trauma that would interfere with absorption of study drug
10. Increased intracranial pressure
11. Respiratory condition requiring intubation
12. History of uncontrolled seizures that are not being managed with anticonvulsants
13. Significant prior history of substance abuse or alcohol abuse
14. Received any investigational drug within 30 days prior to the first dose of study drug, or are scheduled to receive an investigational drug other than oxymorphone HCl immediate-release oral liquid during the course of the study
15. Received a monoamine oxidase inhibitor (MAOI) within 14 days prior to the start of study drug
16. Received oxycodone or oxymorphone within 48 hours prior to study start
17. Investigator anticipates that the subject and/or parent(s)/legal guardian(s) would be unable to comply with the protocol
18. Subject (and/or parent[s]/legal guardian[s]) is(are) unable to communicate effectively with study personnel at an age-appropriate level