Inclusion Criteria:
1. Informed of the nature of the study, agreed to, and able to read, review, and sign the informed consent document prior to dosing. The informed consent document will be written in English; therefore, the subject must have the ability to read and communicate in English.
2. Completed the screening process within 60 days prior to dosing. Subjects screened as a part of an IRB-approved General Screening Protocol at the clinical research site may be included in this study without additional screening procedures provided all the required screening procedures have been performed within 60 days prior to dosing.
3. Healthy male and non-pregnant female subjects between ages 18 and 55, inclusive, at the time of dosing.
4. Body mass index (BMI) between 18.0 kg/m2 to 35.0 kg/m2, inclusive, and weigh at least 60 kg.
5. Judged by the Investigator and/or designee to be in good health as documented by the medical history, physical examination (including but may not be limited to an evaluation of the cardiovascular, gastrointestinal, respiratory and central nervous systems), vital sign assessments along with oxygen saturation, 12-lead electrocardiogram (ECG), clinical laboratory assessments, and by general observations. Any abnormalities or deviations outside the normal ranges for any of clinical testing (laboratory tests, ECG, etc.) can be repeated at the discretion of the Investigator and/or designee and judged to be not clinically significant for study participation. Any abnormalities or deviations outside the normal range for vital signs can be repeated by clinical staff and judged to be not clinically significant for study participation.
6. Subjects with glomerular filtration rate (GFR) of greater than or equal to 60.
Exclusion Criteria:
1. More than three digits absent from the hands due to congenital or accidental cause(s).
2. Reports receiving any investigational drug within 30 days prior to dosing.
3. Reports any personal history of substance abuse (including drug/alcohol abuse or addiction) or mental illness (e.g. major depression) within one year prior to screening visit.
4. Presence of any clinically significant results from laboratory tests, vital signs assessments, as judged by the Investigator.
5. Reports a clinically significant illness during the 30 days prior to dosing (as determined by the Investigator).
6. Reports a history of allergic response(s) to opiates or related drugs, or any of the interferents listed in Section 13 of the protocol.
7. Reports history of respiratory depression (e.g., sleep apnea).
8. Current severe hypotension (i.e., systolic blood pressure \<90 mmHg).
9. With the exception of the five smokers (study subjects 90-95, see Appendices A and B of the protocol), reports a history of tobacco use (smoking, chewing, vaping) within previous two weeks.
10. Report history/current condition of seizures, increased intracranial pressure, brain tumor, head injuries or impaired consciousness.
11. Reports known or suspected gastrointestinal obstruction including, paralytic ileus.
12. Unwilling to consume meals provided by the clinical site.
13. Demonstrates a positive pregnancy screen (females only).
14. Any subject for whom dosing with codeine sulfate as described in this protocol is contraindicated (see Section 9.3.2 and Appendix B of the protocol).
15. If, in the opinion of the Investigator, the subject is not suitable for the study.
