Determining the Effect of Abiraterone on the Metabolism of Oxycodone in Men With Prostate Cancer (the ENABLE Study)

Inclusion Criteria:

* Diagnosed prostate cancer;
* Males aged 18 years or older;
* Treated with abiraterone 1000 mg once daily for at least 10 days (abiraterone arm).
* Not treated with abiraterone 1000 mg once daily for at least 10 days (control arm).

Exclusion Criteria:

* Use of oxycodone short acting \<48 hours, or long acting \<96 hours prior to the study day;
* Use of other opioids in the 14 days prior to the study day (see also appendix A);
* Use of other medication that has pharmacokinetic or pharmacodynamics interactions with oxycodone (see also appendix A);
* Arm 1: dose reduction or successive days of treatment interruption within 10 days prior to the study day (arm 1);
* Arm 2: treatment with abiraterone within 10 days prior to the study day;
* A body mass index (BMI) outside the range of 18 - 30 kg/m2;
* If hypersensitive to oxycodone;
* patients suffering from diarrhea
* If any type of abnormality; active or symptomatic viral hepatitis or chronic liver disease (e.g. classification with Child-Pugh B, Child-Pugh C);
* Known metastases in the liver that would affect drug metabolism;
* Patients with a CYP3A4 or CYP2D6 polymorphism;
* Moderate-severe renal dysfunction (GFR \<60 ml/min/1.73m2) that affects drug metabolism ;
* Subjects with significant respiratory depression resulting in the need of oxygen therapy or objective hypoventilation (respiratory rate \<12/min);
* Hypercapnia (venous pCO2 outside the range of 5.5 - 6.7; pH outside the range 7.30 - 7.40);
* Subjects with, a history of bronchial asthma, chronic obstructive pulmonary disease or pulmonary heart disease;
* Subjects who started their first cycle of chemotherapy during the 2 weeks before the study day;
* Major surgery within 1 month prior to screening or planned surgery;
* A history of drug abuse
* Patients receiving opioid substitution therapy for opioid addiction (e.g. methadone or buprenorphine) and/or suffering from opioid withdrawal
* Patients with evidence of clinically significant gastrointestinal disease;
* Patients who are contraindicated for blood sampling;
* Unable to swallow solid, oral dosage forms whole with water;
* Participation in a clinical trial study at the time of enrolment or within 30 days or 5 half-lives of enrolment, whichever is longer;
* Previous gastric bypass or gastric band surgery.