Abuse-deterrent and tamper-resistant opioids: how valuable are novel formulations in thwarting non-medical use?

Remote local photoactivation of morphine produces analgesia without opioid-related adverse effects

BACKGROUND AND PURPOSE

Opioid-based drugs are the gold standard medicines for pain relief. However, tolerance and several side effects (i.e. constipation and dependence) may occur upon chronic opioid administration. Photopharmacology is a promising approach to improve the benefit/risk profiles of these drugs. Thus, opioids can be locally activated with high spatiotemporal resolution, potentially minimizing systemic-mediated adverse effects. Here, we aimed at developing a morphine photo-derivative (photocaged morphine), which can be activated upon light irradiation both in vitro and in vivo.

EXPERIMENTAL APPROACH

Light-dependent activity of pc-morphine was assessed in cell-based assays (intracellular calcium accumulation and electrophysiology) and in mice (formalin animal model of pain). In addition, tolerance, constipation and dependence were investigated in vivo using experimental paradigms.

KEY RESULTS

In mice, pc-morphine was able to elicit antinociceptive effects, both using external light-irradiation (hind paw) and spinal cord implanted fibre-optics. In addition, remote morphine photoactivation was devoid of common systemic opioid-related undesired effects, namely, constipation, tolerance to the analgesic effects, rewarding effects and naloxone-induced withdrawal.

CONCLUSION AND IMPLICATIONS

Light-dependent opioid-based drugs may allow effective analgesia without the occurrence of tolerance or the associated and severe opioid-related undesired effects.

LINKED ARTICLES

This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.

Abuse Deterrent Formulations in Constraining the Abuse Potential of Prescription Medicines: A Myth or Truth

BACKGROUND

Diverse pain killers used for the management of varied categories of pain are being misused in order to have extreme pleasant effect by a large number of populations. To overcome the misuse of prescription drugs, regulatory bodies have given stress on development of abuse resistance.

METHODS

We studied numerous literatures: (1) Research and review papers including the guidelines for pain management, abuse, and abuse deterrence; (2) Description and categorization of pain along with the management approaches; (3) advantages and disadvantages of the abuse deterrent formulations were described.

RESULTS

Abuse deterrent formulations are the contemporary remedial treatment for pain with reduced prospects of being abused. But these comprise the huge expense in contrast to the generic drugs as well as the non-deterrent branded equivalents.

CONCLUSION

Many challenges are faced throughout the development of abuse deterrent formulations. These formulations displayed substantial drop in abuse incidences but it may lead to other modes of abuse which may prove more harmful for the users.

Pragmatic Opioid Use in Painful Diabetic Neuropathy

The management of painful diabetic neuropathy poses a tough clinical challenge. Although opioid analgesics are considered as second- or third-line agents in the management of moderate-to-severe neuropathic pain, prescription of opioids for this indication is higher than expected. This narrative review is a recommendation on how to ensure pragmatic use of opioids for those with painful diabetic neuropathy while avoiding complications such as opioid overdose, opioid diversion and the development of opioid-use disorder. Risk mitigation strategies at the level of the clinician include periodic assessment and documentation of clinical details, treatment history and psychosocial status. Using a multimodal approach to pain management, medication counselling, adherence monitoring programmes, evidence-based opioid dosing strategies and empowering patients to make treatment decisions are effective strategies in reducing risk associated with prolonged opioid use. At the organisational and policy level, using prescription drug monitoring programmes, carrying out periodic opioid utilisation reviews and providing training to patients and physicians on safe opioid use are useful, implementable strategies.

Important statistical considerations in the evaluation of post-market studies to assess whether opioids with abuse-deterrent properties result in reduced abuse in the community

PURPOSE

Abuse, misuse, addiction, overdose, and death associated with non-medical use of prescription opioids have become a serious public health concern. Reformulation of these products with abuse-deterrent properties is one approach for addressing this problem. FDA has approved several extended-release opioid analgesics with abuse-deterrent labeling, the bases of which come from pre-market studies. As all opioid analgesics must be capable of delivering the opioid in order to reduce pain, abuse-deterrent properties do not prevent abuse, nor do pre-market evaluations ensure that there will be reduced abuse in the community. Utilizing data from various surveillance systems, some recent post-market studies suggest a decline in abuse of extended-release oxycodone after reformulation with abuse-deterrent properties. We discuss challenges stemming from the use of such data.

METHODS

We quantify the relationship between the sample, the population, and the underlying sampling mechanism and identify the necessary conditions if valid statements about the population are to be made. The presence of other interventions in the community necessitates the use of comparators. We discuss the principles under which the use of comparators can be meaningful.

CONCLUSIONS

Results based on surveillance data need to be interpreted with caution as the underlying sampling mechanisms can bias the results in unpredictable ways. The use of comparators has the potential to disentangle the effect due to the abuse-deterrence properties from those due to other interventions. However, identifying a comparator that is meaningful can be very difficult.

Decreased diversion by doctor-shopping for a reformulated extended release oxycodone product (OxyContin)

BACKGROUND

Doctor-shopping (obtaining prescriptions from multiple prescribers/pharmacies) for opioid analgesics produces a supply for diversion and abuse, and represents a major public health issue.

METHODS

An open cohort study assessed changes in doctor-shopping in the U.S. for a brand extended release (ER) oxycodone product (OxyContin) and comparator opioids before (July, 2009 to June, 2010) versus after (January, 2011 to June, 2013) introduction of reformulated brand ER oxycodone with abuse-deterrent properties, using IMS LRx longitudinal data covering >150 million patients and 65% of retail U.S. prescriptions.

RESULTS

After its reformulation, the rate of doctor-shopping decreased 50% (for 2+ prescribers/3+ pharmacies) for brand ER oxycodone, but not for comparators. The largest decreases in rates occurred among young adults (73%), those paying with cash (61%) and those receiving the highest available dose (62%), with a 90% decrease when stratifying by all three characteristics. The magnitude of doctor-shopping reductions increased with increasing number of prescribers/pharmacies (e.g., 75% reduction for ≥2 prescribers/≥4 pharmacies).

CONCLUSIONS

The rate of doctor-shopping for brand ER oxycodone decreased substantially after its reformulation, which did not occur for other prescription opioids. The largest reductions in doctor-shopping occurred with characteristics associated with higher abuse risk such as youth, cash payment and high dose, and with more specific thresholds of doctor-shopping. A higher prescriber and/or pharmacy threshold also increased the magnitude of the decrease, suggesting that it better captured the effect of the reformulation on actual doctor-shoppers.

The Clinical Applications of Extended-Release Abuse-Deterrent Opioids

Opioids are the mainstay for treatment of acute pain and cancer pain, and also have a role in the treatment of chronic non-malignant pain. There has been, however, a growing public health problem stemming from the misuse of opioid analgesics leading to serious consequences. To deter abuse, new formulations of extended-release opioid analgesics and tamper-resistant opioids have recently been developed. The concept of abuse-deterrent extended-release opioids is relatively new and, although abuse may not be completely prevented, the utilization of such abuse-deterrent extended-release opioids could reduce this risk. Extended-release abuse-deterrent opioids have been found to have important clinical applications in cancer, acute pain, and chronic non-malignant pain for analgesia control with decreased incidence of tampering and abuse. In this review, different extended-release formulations of opioids available for clinical applications are presented with descriptions of the formulations, their physical properties, and the clinical studies performed to provide physicians with a better understanding of their uses.

How Resistant to Tampering are Codeine Containing Analgesics on the Market? Assessing the Potential for Opioid Extraction

Introduction

Misuse of opioid analgesics, in combination with diversion, dependence, and fatal overdoses, presents a serious problem for public health, which affects many countries worldwide. Within this context, tampering with opioids has been associated with serious harm. The aim of the present study was to assess the tampering potential of codeine combination analgesics on the market (containing codeine/non-opioid analgesics) by the extraction of codeine.

Methods

Codeine was extracted from three combination formulations sold lawfully from licensed pharmacies without a medical prescription in Denmark and the UK. Extraction of codeine followed tampering procedures available on the Internet. The amounts of codeine and accompanying non-opioid analgesics in tampering products were analysed with liquid chromatography and tandem mass spectrometry (LC–MS/MS).

Results

LC–MS/MS showed recoveries of the total amounts of codeine in tampering products of 81–84% from Product 1 (codeine/acetylsalicylic acid); 61–67% from Product 2 (codeine/ibuprofen); and 42–71% from Product 3 (codeine/paracetamol). Recoveries of non-opioid analgesics ranged between: 57–73% acetylsalicylic acid; 5.5–8.5% ibuprofen, and 5.0–9.2% paracetamol.

Conclusion

With the tampering procedures used, high amounts of codeine were separated from the accompanying analgesics in some, but not in all of the codeine containing formulations. Evidence-based medicine regulation, treatment for opioid dependence, and information to minimise risks to the public are essential components of an effective public health strategy to address the harms of tampering and misuse.

Funding

Marie Pedersen and Jensine Heiberg Foundation.

Opioid Analgesics

Chronic pain is an international health issue of immense importance that is influenced by both physical and psychological factors. Opioids are useful in treating chronic pain but have accompanying complications. It is important for clinicians to understand the basics of opioid pharmacology, the benefits and adverse effects of opioids, and related problematic issues of tolerance, dependence, and opioid-induced hyperalgesia. In this article, the role of psychiatric comorbidity and the use of validated assessment tools to identify individuals who are at the greatest risk for opioid misuse are discussed. Additionally, interventional treatment strategies for patients with chronic pain who are at risk for opioid misuse are presented. Specific behavioral interventions designed to improve adherence with prescription opioids among persons treated for chronic pain, such as frequent monitoring, periodic urine screens, opioid therapy agreements, opioid checklists, and motivational counseling, are also reviewed. Use of state-sponsored prescription drug monitoring programs is also encouraged. Areas requiring additional investigation are identified, and the future role of abuse-deterrent opioids and innovative technology in addressing issues of opioid therapy and pain are presented.

Opioid misuse in Canada and critical appraisal of aberrant behavior screening tools

The incidence of prescription opioid misuse in Canada is increasing. Initiatives for safe prescribing practices for opioid medications include risk assessment for current and future opioid misuse. A clinical screening tool that can be universally applied to all patient populations is currently not available. Our objective was to provide a brief narrative review on opioid misuse from a Canadian perspective as well as a critical appraisal of the available clinical screening tools for detecting aberrant behaviors associated with opioid misuse. The Drug Abuse Screening Test, Addiction Behaviors Checklist, Diagnosis, Intractability, Risk and Efficacy Inventory, Pain Assessment and Documentation Tool, Prescription Drug Use Questionnaire, Prescription Opioid therapy Questionnaire, Screener and Opioid Assessment for Patients with Pain (SOAPP), Revised SOAPP, Pain Medication Questionnaire, Opioid Risk Tool and Current Opioid Misuse Measure were included in the following review. Overall, a wide variability in quality, sensitivity and specificity was observed between screening tools. There is an overall lack of applicability to diverse patient populations as the majority of screening tools have been validated in pain clinic populations only. To conclude, there is a great need for a validated and convenient aberrant behaviors risk assessment tool that can be applied to a diverse patient population in a clinical setting.