Objective: To understand the correlation between oxycodone concentration and drug liking response for immediate-release formulations as they relate to different doses and different routes of administration following manipulation involved in opioid misuse and nontherapeutic use.
Methods: Concentration-response and noncompartmental analyses of drug liking and plasma oxycodone data from Category 3 human abuse potential studies (n = 15-29 per study) were conducted, using Phoenix 6.0 software. Time to onset of a set threshold of subjective effects (Tonset) and offset of subjective effects (Toffset) were estimated based on a baseline pharmacodynamic response set at 50 on a bipolar Drug Liking visual analog scale of 0-100 and the threshold for drug liking set at ≥65, based on study qualification criteria. Partial Area Under the Concentration (AUCTonset-Toffset) and Effect (AUETonset-Toffset) profiles were calculated and their correlation with individual partial AUE vs partial AUC was assessed.
Results: The oxycodone concentration-response (drug liking) was best described by a sigmoidal-effect Emax model (S-shaped). Using a defined threshold, drug liking was closely associated with the rate of rise in concentration and the onset of action for oxycodone administered via oral or intranasal route. Partial AUCTonset-Toffset and AUETonset-Toffset showed a strong linear correlation.
Conclusions: Results indicate that oxycodone concentration-response and duration of drug liking following manipulation via different routes of administration may be an approach for further exploring drug liking effects of opioids.
Keywords: Concentration-Response; Drug Liking; Immediate-Release; Misuse; Oxycodone.
Published by Oxford University Press on behalf of the American Academy of Pain Medicine. This work is written by US Government employees and is in the public domain in the US.