A repeat patch application study to determine what the body does to oxycodone in combination with tocopheryl phosphate mix, when delivered through the skin using different methods of repeat application.

Exclusion Criteria20

• History or evidence of drug abuse and/or positive repeat urine results prior to start of the study. History or evidence of alcohol abuse and/or positive repeat urine/breath test results prior to start of the study.
• Individuals who smoked an average of one or more cigarette or tobacco form (including cigars) per month in the last 12 months.
• Current use of central nervous system (CNS) depressants including: other opioids, sedative/hypnotics, phenothiazines, tranquillisers, skeletal muscle relaxants or sedating antihistamines.
• Use of macrolide antibiotics (e.g., Erythromycin), azole antifungal agents (e.g., Ketoconazole) or protease inhibitors (e.g., Ritanovir) within 30 days of study dosing.
• Evidence of clinically relevant oral, cardiovascular, haematological, gastrointestinal, hepatic, renal, endocrine, pulmonary, neurologic, psychiatric or skin disorders.
• History of epilepsy.
• History of coronary diseases, peripheral vascular diseases, cerebrovascular accident, transient ischaemic attack, uncontrolled hypertension or signs/symptoms of ischaemic heart disease e.g., Hypertension where blood pressure (BP) is persistently greater than 140/95 mmHg.
• Any pre-existing medical conditions predisposing the subject to hypoventilation or hypoxaemia.
• Known allergy or hypersensitivity reactions to naltrexone or to oxycodone, or other opioid analgesics (codeine, fentanyl, hydrocodone, morphine etc.), or allergy to any contents of the gel or patch materials.
• Known allergy or hypersensitivity to Tegaderm patches or to topical preparations, such as sunscreens.
• A calculated creatinine clearance (CL) of less than 85ml/min.
• Positive screening test for Human Immunodeficiency Virus (HIV) antibodies, Hepatitis B surface antigen or Hepatitis C antibody.
• Use of any prescription medication during the 14 days prior to study dosing, unless approved by both the Principal Investigator (PI) and the Sponsor. If necessary, paracetamol (acetaminophen) may be received for mild analgesia prior to, or during, the study.
• Use of any over the counter product, herbal product, diet aid, hormone supplement, etc., within 14 days prior to dosing unless approved by both the PI and the Sponsor.
• Have participated in a clinical trial or receipt of an experimental therapy within 30 days prior to dosing, other than subjects who undertook the Naltrexone challenge successfully as alternates for earlier cohorts of this study.
• Blood donation of greater than 550 mL within 90 days before the first dose administration.
• Have a history of low BP or severe motion sickness e.g., hypotension where BP is persistently less than 90/50 mmHg.
• Consumption of grapefruit or grapefruit juice within 14 days prior to the first day of study confinement and through to completion of the confinement period.
• Regularly drink more than four (4) units of alcohol daily (1 unit = 300 mL beer, 1 glass of wine, 1 measure of spirit) or who may have difficulty abstaining from alcohol during the 36 hours prior to dose administration and until completion of blood sampling.
• Any tattoos on the area where the study drug is to be applied.