A Randomized, Double-Blind, Double-Dummy Study to Evaluate the Intranasal Human Abuse Potential and Pharmacokinetics of a Novel Extended-Release Abuse-Deterrent Formulation of Oxycodone

A Cross-Sectional Study of Tampering in Xtampza ER, an Abuse-Deterrent Formulation of an Extended-Release Opioid, in a Treatment Center Population

BACKGROUND AND OBJECTIVE

While the current landscape of opioid use disorder (OUD) is complicated by the increase in use of non-prescription opioids, prescription opioids continue to be frequently used in non-medical ways. In response to this abuse, pharmaceutical companies have developed abuse deterrent formulations (ADFs) for extended-release (ER) opioids. To test the effectiveness of Xtampza ER ADF (oxycodone myristate) at reducing tampering, its rate of tampering in a treatment-center population was compared to immediate release (IR) single entity (SE) oxycodone, other ER oxycodone opioids, and ER oxymorphone.

METHODS

Data were collected between the third quarter of 2018 and the third quarter of 2021 from individuals entering nationally distributed opioid treatment programs. To determine odds of tampering with Xtampza ER compared to each comparator, a logistic model was fit with a random intercept allowing for multiple drugs in each subject. Within-subject correlation was assumed to have a compound symmetric relationship.

RESULTS

Overlap among the categories of drug tampering was high. Logistic regression analyses found that oxycodone myristate had lower odds of tampering when compared to both IR SE oxycodone (OR = 0.23 [95% CI 0.11, 0.50], p = 0.0002) and ER oxymorphone (OR = 0.30 [95% CI 0.14, 0.67], p = 0.0038). Oxycodone myristate was not significantly different from other ER oxycodone opioids (OR = 0.5 [95% CI 0.24, 1.03], p = 0.0612). These findings did not change when the estimates were adjusted for age and sex.

CONCLUSIONS

Drugs employing ADF technology may reduce the likelihood of tampering when compared to non-ADF formulations in a treatment-center population, which represents an opportunity for intervention in OUD among those still requiring pain management.

Pharmacokinetics of Buprenorphine Buccal Film and Orally-administered Oxycodone in a Respiratory Study: An Analysis of Secondary Outcomes from a Randomized Controlled Trial

OBJECTIVE

To evaluate pharmacokinetic (PK) parameters and oxygen saturation as markers of abuse potential after administration of buprenorphine buccal film (BBF) and immediate-release (IR) oxycodone.

METHODS

This was a secondary analysis of data from a phase I randomized controlled trial. A total of 19 healthy subjects who self-identified as recreational opioid users were enrolled, with 15 completing the study. Subjects were administered 300, 600, and 900 µg BBF; 30 and 60 mg orally-administered oxycodone; and placebo. For PK analysis, blood samples were collected before dosing and at 0.5, 1, 2, 3, 4, and 6 h postdose. Respiratory drive/ventilatory response to hypercapnia and oxygen saturation were evaluated before dosing and up to 8 h after administration of test drugs.

RESULTS

Median time to maximum concentration (T_max) was 2.17 h for 900 µg BBF and 1.17 h for 60 mg oxycodone and was similar across all doses for each drug. Mean maximum concentration (C_max) was 1.06 ng/mL for 900 µg BBF and 132 ng/mL for 60 mg oxycodone. The abuse quotient, defined as C_max/T_max, was substantially higher for oxycodone compared to BBF. Respiratory depression (maximum decrease in minute ventilation) was similar for all 3 doses of BBF, consistent with a potential ceiling effect. In addition, respiratory depression occurred sooner with oxycodone vs BBF, and a greater mean decrease in oxygen saturation was observed for oxycodone 30- and 60-mg doses, compared with BBF.

CONCLUSION

These results indicate that BBF may have a decreased risk of abuse and respiratory depression compared with the full µ-opioid receptor agonist oxycodone.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03996694.

Association of partial systemic exposure and abuse potential for opioid analgesics with abuse deterrence labeling claims supporting product-specific guidance

BACKGROUND

Over the past decade, U.S. FDA has approved 10 opioid analgesics in abuse-deterrent formulations (ADFs). ADFs are intended to reduce abuse of a prescription opioid through manipulation of the product to use one or more routes of abuse. Although it is critically needed for evaluation of the abuse deterrent properties of an opioid product, the relationship between systemic exposure and likelihood of abuse of the opioid has not been fully characterized. To fill the current knowledge gap, we have evaluated the association of subjective measures predictive of abuse potential (e.g., scores of "drug liking," "take drug again"), which are referred to as 'pharmacodynamic (PD)' responses for measuring abuse potential, with systemic exposure of the opioid using the data from all the clinical abuse potential trials submitted to FDA in support of the approval of innovator ADFs.

METHODS

Extensive pharmacokinetic (PK) and subjective response data from 11 clinical abuse potential trials in recreational opioid users following oral and nasal administration of intact and manipulated oxycodone, hydrocodone and morphine products from the FDA internal database were utilized for the present analysis. This retrospective study used data collected from January 11^th, 2010 until March 25^th, 2015. The potential relationship between PK metrics, especially those for early exposure measures, and the subjective measures of drug liking and take drug again as PD metrics of abuse potential were explored using linear and logistic regression analyses. Heterogeneity analysis was conducted to assess study-to-study variation and multi-level logistic regression analysis was used to affirm the identified PK-PD relationship based on pooled data.

FINDINGS

Following oral and nasal administration of intact and manipulated opioids, the maximum visual analogue scale (VAS) for Drug Liking was generally achieved no later than the time to peak plasma drug concentration. Both heterogeneity analysis and multi-level logistic regression indicated insignificant inter study variability for the evaluated PK-PD relationships. Duration of Drug Liking response (i.e., VAS ≥ 65) lasted for 2 to 4 h after drug administration. The early portion of the systemic area under the plasma concentration-time curve (AUC), e.g., partial AUCs in the first 3 h and 4 h were found to be associated with abuse potential measures including maximum Drug Liking VAS and maximum Taking Drug Again VAS. Neither a formulation factor (e.g., immediate-release vs. extended-release, intact vs. manipulated) nor a route of administration was identified as a significant factor together with early partial AUCs to predict the probability of maximum Drug Liking or maximum Take Drug Again responses being greater than or equal to 65.

INTERPRETATION

Our assessment indicates that the measure of early systemic drug exposure of opioids is the best predictor of the abuse potential response in recreational opioid users following oral or nasal administration of a single dose of an intact or manipulated abuse deterrent opioids. Our findings support FDA's recommendation of comparative PK studies with early partial AUCs as a supportive PK metric for the assessment of abuse deterrent properties of generic opioid drug products in the general and product-specific guidance's of ADFs.

FUNDING

The study was partially funded by Fiscal Year 2017 Critical Path of the Center for Drug Evaluation and Research at the U.S. Food and Drug Administration.

Oxycodone Effect on Pupil Constriction in Recreational Opioid Users: A Pharmacokinetic/Pharmacodynamic Meta-Analysis Approach

INTRODUCTION

Understanding the effect of oxycodone pharmacokinetics (PK) on µ-opioid receptor binding benefits from an integrated approach to compiling the results of multiple studies. The current pharmacokinetic/pharmacodynamic (PK/PD) model analysis brings together various studies to support the interpretation of newly collected PK/PD data, putting the new results into the perspective of the full concentration-effect curve.

METHODS

A two-step modeling approach was applied to characterize the PK of oxycodone and its PK/PD relationship for the pupil diameter as a biomarker for µ-opioid receptor binding in recreational opioid users. First, a model-based meta-analysis (MBMA) was used to quantify the state-of-the-art knowledge from seven published studies, each of which contained part of the data needed for full characterization. Subsequently, the estimated parameters with uncertainty from the MBMA were used as prior information for a model developed on newly collected clinical data after intranasal administration in a clinical abuse potential trial.

RESULTS

The inclusion of intravenous data in the MBMA showed that the PK of oxycodone can be described by a two-compartmental model, and allowed for the estimation of absolute bioavailability after intranasal and oral administration. A hysteresis loop was observed when plotting plasma concentrations and pupil constriction, which was approximated using an effect compartment. The totality of literature data enabled the identification of a Hill equation for the drug effect. The model with prior information fitted successfully to the newly collected data, where most parameter estimates had their confidence intervals overlapping with the prior distribution. The new data led to a slightly lower intranasal absorption rate constant, explaining the longer apparent half-life of oxycodone in the newly collected data. The PK/PD model parameters were confirmed by the new data, leading to the following estimates: half maximal inhibitory concentration (IC₅₀) of 26.5 ng/mL, maximum pupil restriction of 66.0% from baseline, and a Hill factor of 1.05.

CONCLUSIONS

The new data confirmed the PK profile and the PK/PD relationship identified using the MBMA, resulting in similar parameter estimates except for the intranasal absorption rate constant. The latter was lower than in the MBMA and explained the slightly longer apparent half-life of oxycodone in the newly collected data.

An overview of abuse-deterrent opioids and recommendations for practical patient care

Despite advances in the treatment of severe intractable pain, opioids remain a critical and appropriate component of treatment. However, abuse, misuse, and diversion of prescription opioids are significant public health concerns. Opioid abuse-deterrent formulations (ADFs) are one component of an opioid risk management plan to manage patient’s pain relief and quality of life while offering some protection against potentially harmful consequences of opioids from misuse and abuse. Opioid ADFs are designed to make manipulation more difficult and administration via non-oral routes less appealing. There are currently nine extended-release and one immediate-release opioid pain medications with US Food and Drug Administration-approved ADF labeling. All use physical/chemical barriers or agonist/antagonist combinations to deter manipulation and abuse. Evidence suggests that opioid ADFs decrease rates of abuse and diversion of opioids in the USA; however, some opioid ADFs are not yet commercially available or have not been on the market long enough to undergo post-marketing data analyses. Opioid ADFs along with the use of prescription drug monitoring programs, clinical assessment tools, toxicology testing, and co-prescribing of naloxone are all tools that can be used to reduce opioid abuse. Patient education on the risks of abuse and diversion is vital and includes a discussion of appropriate use of medication and proper storage. Physician assistants and nurse practitioners are on the “front lines” in battling opioid abuse and serve a key role in recognizing and mitigating the risks of prescription opioid diversion, abuse, and misuse (intentional and unintentional) and in identifying patients at risk for abuse while still providing pain relief to patients.

In Vitro Drug Release After Crushing: Evaluation of Xtampza® ER and Other ER Opioid Formulations

Background and Objective

Extended-release (ER) opioids are associated with high rates of abuse. Recreational opioid users often manipulate ER formulations to achieve a high plasma concentration in a short amount of time, resulting in a more rapid and intense high. Patients may also manipulate ER tablets to facilitate swallowing, without recognizing that manipulation could increase release rate. The goal of this study was to assess the ability of oxycodone DETERx (Xtampza^® ER, Collegium Pharmaceutical, Inc., Canton, MA, USA) and other commercially available ER opioid formulations with and without physicochemical abuse-deterrent characteristics to be manipulated by crushing in an in vitro setting.

Methods

In vitro dissolution techniques were used to compare the opioid release from a variety of ER opioid formulations. Dissolution was assessed for intact and crushed dosage forms. Opioid release was quantified using high-performance liquid chromatography.

Results

Intact formulations exhibited drug release rates characteristic of 12- or 24-h dosage forms. After crushing using commonly available household tools, only Xtampza ER maintained ER of opioid.

Conclusions

Xtampza ER maintained its ER characteristics after crushing, unlike many other commercially available opioid formulations, including some formulated with abuse-deterrent properties. As such, Xtampza ER may be less appealing to abusers and offer a margin of safety for patients who manipulate dosage forms to facilitate swallowing.

Oxycodone DETERx®: A Novel Abuse-Deterrent, Extended-Release Analgesic Option for the Treatment of Patients with Chronic Pain

BACKGROUND

Extended-release (ER) opioid analgesics are commonly used to provide safe and effective pain relief to treat pain severe enough to require around-the-clock, long-term dosing. These ER opioid formulations usually contain more drug per dosage unit than immediate-release (IR) agents, and therefore bring with them challenges related to both opioid abuse and misuse, often through manipulation of the dosage form. Oxycodone DETERx® (Xtampza® ER, Collegium Pharmaceutical, Inc.) is a novel abuse-deterrent, ER formulation developed to deter common methods of manipulation. In addition to having abuse-deterrent properties, oxycodone DETERx was developed to provide alternative modes of administration for patients with chronic pain and difficulty swallowing.

SCOPE

Using published articles, abstracts, and prescribing information, data supporting the use of oxycodone DETERx are reviewed.

FINDINGS

Oxycodone DETERx was effective at reducing chronic pain in patients enrolled in a pivotal clinical trial, and had a tolerability profile expected of opioids. In addition to administration of the intact capsule, oxycodone DETERx can also be administered by sprinkling directly into the mouth from a dosing cup, onto soft foods, or through nasogastric or gastrostomy tubes, thus providing flexible dosing options for patients who have difficulty swallowing. In vitro studies demonstrated the reduced ability of oxycodone DETERx to be manipulated by common techniques used by abusers to defeat the ER characteristics or prepare the formulation for injection. Pharmacokinetic studies demonstrated that the ER characteristics of oxycodone DETERx are maintained if chewed or crushed. As a result, oxycodone DETERx is currently the only ER-formulated opioid without a boxed warning against crushing or chewing. Human abuse-potential studies conducted in a population of recreational opioid users demonstrated lower drug-liking scores for oxycodone DETERx administered intranasally and orally when compared with IR oxycodone.

FUNDING

Collegium Pharmaceutical, Inc.