Effects of LRYGB on Pharmacokinetics of Nine CYP Probe Drugs
Summary
Due to anatomical and physiological changes caused by the Roux-en-Y gastric bypass (RYGB) bariatric surgery, drug bioavailability after the surgery can be altered. Therefore, post-operative dose adjustment in these patients can be required. The aim of the study was to investigate the effects of laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery on drug pharmacokinetics and cytochrome P450 (CYP) mediated metabolism using a cocktail of nine CYP probe drugs. The cocktail covers nine main CYP enzymes: melatonin (CYP1A2), nicotine (CYP2A6), bupropion (CYP2B6), repaglinide (CYP2C8), losartan (CYP2C9), omeprazole (CYP2C19/CYP3A4), dextromethorphan (CYP2D6), chlorzoxazone (CYP2E1), midazolam (CYP3A4). The changes in pharmacokinetic parameters of the drugs as well as modulation of the activity of CYPs are evaluated before and one year after LRYGB. In the study, the patients administering drug cocktail before surgery and 1 year after LRYGB are served as their own controls.
Timeline
- Start
- 2012-01-27
- Primary completion
- 2014-12-10
- Completion
- 2014-12-10
Drugs
| Evaluation | Drug | Modality | Dose | Route |
|---|---|---|---|---|
| Subject | Bupropion | Small molecule | 37.5 mg | Oral |
| Subject | Chlorzoxazone | Small molecule | 62.5 mg | Oral |
| Subject | Dextromethorphan | Unknown | 30 mg | Oral |
| Subject | Losartan | Other / unclassified | 12.5 mg | Oral |
| Subject | Melatonin | Small molecule | 2 mg | Oral |
| Subject | Midazolam | Small molecule | 1.85 mg | Oral |
| Subject | Nicotine | Unknown | 1 mg | Oral |
| Subject | Omeprazole | Other / unclassified | 10 mg | Oral |
| Subject | Repaglinide | Small molecule | 0.25 mg | Oral |