Despite the widespread use and availability of cannabis products, substantive deficiencies remain regarding the potential risks for cannabis or cannabinoids to precipitate adverse interactions with conventional drugs. Evidence from the few systematic clinical studies that have been conducted suggests that THC and CBD can inhibit metabolism of other drugs, via interactions with cytochrome P450 (CYP) enzymes, a large family of enzymes involved in the metabolism of numerous drugs and foreign chemicals in the body. Accordingly, evaluating the potential for drug-drug interactions between cannabis-derived products and common CYP-metabolized drugs merits further investigation. This double-blind, randomized crossover design study will evaluate whether, and to what extent, oral administration of cannabis extracts containing high doses of CBD and/or THC alter the pharmacokinetics of 5 drugs metabolized via CYP pathways including: caffeine (CYP1A2), omeprazole (CYP2C19), losartan (CYP2C9), dextromethorphan (CYP2D6), and midazolam (CYP3A). Healthy adults will complete three experimental dosing sessions, in which participants will orally ingest brownies containing (1) a high THC cannabis extract with a target THC dose of 40mg, (2) a high CBD cannabis extract with a target CBD dose of 1350mg + a THC dose of 40mg, or (3) placebo. In all three experimental dosing sessions, consumption of the cannabis extract infused brownie will be followed by ingestion of a drug cocktail comprised of commercial formulations of therapeutic or subtherapeutic doses of each drug. This collection of probe drugs, coined the Inje Cocktail, has been demonstrated to be safe, both administered alone and with various CYP450 inhibitors. At baseline and following administration of the study drugs, a battery of subjective, physiological, and cognitive performance assessments will be completed and biological specimens obtained. Each session will consist of a 12-hour outpatient drug administration visit and a 1-hour outpatient visit the subsequent day for additional biospecimen collection, cognitive testing, and subjective drug effect questionnaires. The study will conclude when 18 participants complete all 3 experimental sessions. The outcomes of this study will be useful to inform clinical decision-making regarding co-administration of cannabinoid-containing products with drugs that are either commonly prescribed by physicians or readily available over-the-counter.
This study will evaluate drug-drug interactions between cannabis extracts containing Tetrahydrocannabinol (THC) and THC+ Cannabinoids (CBD) and probe drugs for select CYP450 pathways including: caffeine (CYP1A2), omeprazole (CYP2C19), losartan (CYP2C9), dextromethorphan (CYP2D6), and midazolam (CYP3A).