Abuse-deterrent Opioid Formulations

Review of Opioid Abuse-Deterrent Formulations: Impact and Barriers to Access

The misuse and abuse of opioid analgesics continue to pose a serious public health concern, but for some patients, opioids remain an important analgesic option. Extended-release (ER) opioid formulations are effective for treating chronic pain and are supported by multiple 12-week efficacy studies. ER opioids often contain a high opioid content, and similar to immediate-release (IR) formulations, are subject to abuse, misuse, and diversion. Unintentional misuse may also occur when ER formulations are manipulated for medicinal administration, such as crushing a dose for easier oral intake. As part of a multipronged strategy designed to fight the opioid epidemic, abuse-deterrent formulations (ADFs) were developed to deter misuse, abuse, and diversion of opioids by making manipulation more difficult and nonoral routes of administration less rewarding. Although ADF opioids have been shown to decrease rates of abuse and diversion, they are not equally effective in terms of deterring manipulation for abuse or misuse. Xtampza ER utilizes DETERx technology, which allows it to retain ER characteristics when chewed or crushed, making it the only ER opioid without a boxed warning against these types of manipulation. OxyContin was also developed as an ADF but uses RESISTEC technology, making the tablet hard to crush and viscous in aqueous solutions. ADF utilization has been hampered by patient access issues, including high prices due to lack of insurance coverage. Postmarket real-world studies demonstrate lower rates of abuse, misuse, and diversion for ADF ER opioids compared with non-ADF formulations. However, similar studies comparing abuse-related effectiveness and health care costs for ADF opioids are warranted if clinicians are expected to utilize these potentially safer opioid formulations. These studies would support further education surrounding the benefits and utilization of ADFs and manipulation potential of different ADFs.

Matching study design to prescribing intention: The prevalent new-user design for studying abuse-deterrent formulations of opioids

PURPOSE

In drug studies, research designs requiring no prior exposure to certain drug classes may restrict important populations. Since abuse-deterrent formulations (ADF) of opioids are routinely prescribed after other opioids, choice of study design, identification of appropriate comparators, and addressing confounding by "indication" are important considerations in ADF post-marketing studies.

METHODS

In a retrospective cohort study using claims data (2006-2018) from a North Carolina private insurer [NC claims] and Merative MarketScan [MarketScan], we identified patients (18-64 years old) initiating ADF or non-ADF extended-release/long-acting (ER/LA) opioids. We compared patient characteristics and described opioid treatment history between treatment groups, classifying patients as traditional (no opioid claims during prior six-month washout period) or prevalent new users.

RESULTS

We identified 8415 (NC claims) and 147 978 (MarketScan) ADF, and 10 114 (NC claims) and 232 028 (MarketScan) non-ADF ER/LA opioid initiators. Most had prior opioid exposure (ranging 64%-74%), and key clinical differences included higher prevalence of recent acute or chronic pain and surgery among patients initiating ADFs compared to non-ADF ER/LA initiators. Concurrent immediate-release opioid prescriptions at initiation were more common in prevalent new users than traditional new users.

CONCLUSIONS

Careful consideration of the study design, comparator choice, and confounding by "indication" is crucial when examining ADF opioid use-related outcomes.

Efficacy of high-voltage, long-duration pulsed radiofrequency for the treatment of acute herpes zoster-related trigeminal neuralgia in a patient with permanent pacemaker

Background

Recognizing the seriousness of the misuse and abuse of medical narcotics, the South Korean government introduced the world's first narcotic management system, the Narcotics Information Management System (NIMS). This study aimed to explore the recent one-year opioid prescribing patterns in South Korea using the NIMS database.

Methods

This study analyzed opioid prescription records in South Korea for the year 2022, utilizing the dispensing/administration dataset provided by NIMS. Public data from the Korean Statistical Information Service were also utilized to explore prescription trends over the past four years. The examination covered 16 different opioid analgesics, assessed by the total number of units prescribed based on routes of administration, type of institutions, and patients’ sex and age group. Additionally, the disposal rate for each ingredient was computed.

Results

In total, 206,941 records of 87,792,968 opioid analgesic units were analyzed. Recently, the overall quantity of prescribed opioid analgesic units has remained relatively stable. The most prescribed ingredient was oral oxycodone, followed by tapentadol and sublingual fentanyl. Tertiary hospitals had the highest number of dispensed units (49.4%), followed by community pharmacies (40.2%). The highest number of prescribed units was attributed to male patients in their 60s. The disposal rates of the oral and transdermal formulations were less than 0.1%.

Conclusions

Opioid prescription in South Korea features a high proportion of oral formulations, tertiary hospital administration, pharmacy dispensing, and elderly patients. Sustained education and surveillance of patients and healthcare providers is required.

Fentanyl in cancer pain management: avoiding hasty judgments and discerning its potential benefits

Cancer pain is an important challenge in treatment and requires a rapid onset of action for its control. In particular, breakthrough cancer pain (BTcP) should be adequately controlled with a stable dose of a short-acting oral opioid. Fentanyl is a synthetic, highly selective opioid with many advantageous chemical properties, including high lipophilicity and distinct pharmacokinetic properties. It is recommended for pain management in a variety of settings, including acute pain, chronic pain and BTcP. To date, its variously designed formulations allow non-invasive administration; amongst others, sublingual fentanyl has proven useful in the management of BTcP and in improving the quality of life of patients with cancer. This review provides an update on the management of BTcP with fentanyl, with consideration of safety, as it remains an important tool in the treatment of cancer pain.

A Chewing Study of Abuse-Deterrent Tablets Containing Polyethylene Oxide Using a Robotic Simulator

Abuse-deterrent formulations (ADFs) refer to formulation technologies aiming to deter the abuse of prescription drugs by making the dosage forms difficult to manipulate or extract the opioids. Assessments are required to evaluate the performance of the drugs through different routes including injection, ingestion, and insufflation and also when the drugs are manipulated. Chewing is the easiest and most convenient way to manipulate the drugs and deserves investigation. Chewing is one of the most complex bioprocesses, where the ingested materials are subject to periodic tooth crushing, mixed through the tongue, and lubricated and softened by the saliva. Inter- and intra-subject variations in chewing patterns may result in different chewing performances. The purpose of this study is to use a chewing simulator to assess the deterrent properties of tablets made of polyethylene oxide (PEO). The simulator can mimic human molar grinding with variable chewing parameters including molar trajectory, chewing frequency, and saliva flow rate. To investigate the effects of these parameters, the sizes of the chewed tablet particles and the chewing force were measured to evaluate the chewing performance. Thirty-four out of forty tablets were broken into pieces. The results suggested that the simulator can chew the tablets into smaller particles and that the molar trajectory and saliva flow rate had significant effect on reducing the size of the particles by analysis of variance (ANOVA) while the effect of chewing frequency was not clear. Additionally, chewing force can work as an indicator of the chewing performance.

Association between recent overdose and chronic pain among individuals in treatment for opioid use disorder

Chronic pain increases risk for opioid overdose among individuals with opioid use disorder. The purpose of this study is to evaluate the relationship between recent overdose and whether or not chronic pain is active. 3,577 individuals in treatment for opioid use disorder in 2017 or 2018 were surveyed regarding recent overdoses and chronic pain. Demographics from the 2017 Treatment Episode Data Set, which includes all U.S. facilities licensed or certified to provide substance use care, were used to evaluate the generalizability of the sample. χ2 tests and logistic regression models were used to compare associations between recent overdoses and chronic pain. Specifically, active chronic pain was associated with opioid overdose among people in treatment for opioid use disorder. Individuals with active chronic pain were more likely to have had a past month opioid overdose than those with no history chronic pain (adjusted OR = 1.55, 95% CI 1.16-2.08, p = 0.0003). In contrast, individuals with prior chronic pain, but no symptoms in the past 30 days, had a risk of past month opioid overdose similar to those with no history of chronic pain (adjusted OR = 0.88, 95% CI 0.66-1.17, p = 0.38). This suggests that the incorporation of treatment for chronic pain into treatment for opioid use disorder may reduce opioid overdoses.

Opioid epidemic: lessons learned and updated recommendations for misuse involving prescription versus non-prescription opioids

INTRODUCTION

In the past decades, the opioid crisis has heavily impacted parts of the US society and has been followed by an increase in the use of opioids worldwide. It is of paramount importance that we explore the origins of the US opioid epidemic to develop best practices to tackle the rising tide of opioid overdoses.

AREAS COVERED

In this expert review, we discuss opioid (over)prescription, change in perception of pain, and false advertisement of opioid safety as the leading causes of the US opioid epidemic. Then, we review the evidence about opioid dependence and addiction potential and provide current knowledge about predictors of aberrant opioid-related behavior. Lastly, we discuss different approaches that were considered or undertaken to combat the rising tide of opioid-related deaths by regulatory bodies, pharmaceutical companies, and health-care professionals. For this expert review, we considered published articles relevant to the topic under investigation that we retrieved from Medline or Google scholar electronic database.

EXPERT OPINION

The opioid epidemic is a dynamic process with many underlying mechanisms. Therefore, no single approach may be best suited to combat it. In our opinion, the best way forward is to employ multiple strategies to tackle different underlying mechanisms.

Controlling drug release by introducing lipase inhibitor within a lipid formulation

Drug overdose connected to marketed pharmaceutical products, particularly opioids, occurs at an alarming rate. Novel strategies through innovative formulation approaches that reduce the likelihood of overdose while allowing safe therapeutic outcomes are urgently required. The current study provides a proof-of-concept for a new formulation approach by co-formulating drug with a lipase inhibitor within a solid lipid formulation in order to prevent or reduce the harmful effects of taking multiple doses of an oral solid dose form. Lipase inhibitor controlled-release (LICR) formulations were created using a simple hot melt method to co-formulate the inhibitor (orlistat) and ibuprofen, as the model drug, within the lipid matrix. The digestion and drug release kinetics were determined using an in vitro lipolysis model. Above a threshold level of orlistat there was decreased digestibility of multiple doses of the LICR formulations, leading to reduced drug release. Upon administration of the formulations in capsules to rats, the LICR formulation displayed the lowest exposure of ibuprofen during the pharmacokinetic studies. This novel formulation approach shows promise in preventing accidental drug overdose after oral administration of multiple doses of formulation.

An overview of the use and misuse/abuse of opioid analgesics in different world regions and future perspectives

Opioids are an important therapeutic option for severe resistant chronic pain but, in the absence of proper oversight, their use has risks. The level of prescription opioid misuse/abuse differs among countries, due to differences in healthcare systems and pain management approaches. However, evaluating the true dimension of prescription opioid misuse/abuse is complicated by statistical reporting which often does not differentiate between prescription and illicit opioid use, or between prescription opioid use by patients and nonpatients, highlighting a need for greater uniformity. Parallel efforts to educate patients and the general public about opioid risks, facilitate appropriate analgesic prescribing and identify alternative formulations or options to use instead of or with opioids, may contribute to optimizing prescription opioid use for pain management.

Emerging trends in Abuse-Deterrent Formulations: Technological insights and Regulatory considerations

BACKGROUND

Opioid medications are an integral part in the management of acute and chronic severe pain. However, non-medical practice of these prescription drug products is emerging as a serious public health problem. To control this opioid epidemic, USFDA is encouraging pharmaceutical companies to develop Abuse Deterrent Formulations (ADFs). Abuse Deterrent Formulations are much more difficult to manipulate and abuse when compared to their conventional formulations. This feature of ADFs is due to their ability to incumber extraction of active ingredients, to prevent administration through alternative routes and making abuse of altered product less rewarding.

OBJECTIVE

The main objective of this review is to abridge different ADFs and various laboratory-based in vitro manipulation and extraction studies, demonstrating that these approved ADFs have capabilities to deter abuse.

METHODS

The method includes collection of data from different search engines like PubMed, FDA guidance documents, ScienceDirect, Google Patents to get coverage of literature in order to get appropriate information regarding ADFs.

RESULTS

Various in vitro studies demonstrate that ADFs are effective in minimizing opioid drug abuse including opioid overdose. However, real impact of these ADFs on reducing the drug abuse can be concluded only after receiving the post marketing data.

CONCLUSION

ADFs are embracing fundamentally different paradigm in management of severe pain. We believe that development of abuse deterrent technologies would shift the architype, deterring multipill abuse and can prove as a breakthrough strategy in controlling this opioid epidemic menace.

Abuse-Deterrent Opioids: A Survey of Physician Beliefs, Behaviors, and Psychology

Objective

Evaluate beliefs and behaviors pertaining to abuse-deterrent opioids (ADFs).

Design

Survey in 2019 by invitation to all licensed physicians.

Setting

Commonwealth of Kentucky.

Participants

374 physicians.

Methods

Descriptive statistics, and hypothesis test that early adopter prescribers would have greater endorsement of opioid risk management.

Results

Of all prescribers, 55% believed all opioid analgesics should have ADF requirements (15% were unsure); 74% supported mandating insurance coverage. Only one-third considered whether an opioid was ADF when prescribing, motivated by patient family diversion (94%) and societal supply reduction (88%). About half believed ADFs were equally effective in preventing abuse by intact swallowing, injection, chewing, snorting, smoking routes. Only 4% of OxyContin prescribers chose it primarily because of ADF properties. Instead, the most common reason (33%) was being started by another prescriber. A quarter of physicians chose not to prescribe ADFs because of heroin switching potential. Early adopters strongly believed ADFs were effective in reducing abuse (PR 3.2; 95% CI 1.5, 6.6) compared to mainstream physicians. Early-adopter risk-management practices more often included tools increasing agency and measurement: urine drug screens (PR 2.0; 1.3, 3.1), risk screening (PR 1.3; 0.94, 1.9). While nearly all respondents (96%) felt that opioid abuse was a problem in the community, only 57% believed it was a problem among patients in their practice. Attribution theory revealed an externalization of opioid abuse problems that deflected blame from patients on to family members.

Conclusions

The primary motivator for prescribing ADFs was preventing diversion by family members, not patient-level abuse concerns.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00343-z.

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.

Oxycodone in the Opioid Epidemic: High 'Liking', 'Wanting', and Abuse Liability

It is estimated that nearly a third of people who abuse drugs started with prescription opioid medicines. Approximately, 11.5 million Americans used prescription drugs recreationally in 2016, and in 2018, 46,802 Americans died as the result of an opioid overdose, including prescription opioids, heroin, and illicitly manufactured fentanyl (National Institutes on Drug Abuse (2020) Opioid Overdose Crisis. https://www.drugabuse.gov/drugs-abuse/opioids/opioid-overdose-crisis . Accessed 06 June 2020). Yet physicians will continue to prescribe oral opioids for moderate-to-severe pain in the absence of alternative therapeutics, underscoring the importance in understanding how drug choice can influence detrimental outcomes. One of the opioid prescription medications that led to this crisis is oxycodone, where misuse of this drug has been rampant. Being one of the most highly prescribed opioid medications for treating moderate-to-severe pain as reflected in the skyrocketed increase in retail sales of 866% between 1997 and 2007, oxycodone was initially suggested to be less addictive than morphine. The false-claimed non-addictive formulation of oxycodone, OxyContin, further contributed to the opioid crisis. Abuse was often carried out by crushing the pills for immediate burst release, typically by nasal insufflation, or by liquefying the pills for intravenous injection. Here, we review oxycodone pharmacology and abuse liability as well as present the hypothesis that oxycodone may exhibit a unique pharmacology that contributes to its high likability and abuse susceptibility. We will discuss various mechanisms that likely contribute to the high abuse rate of oxycodone including clinical drug likability, pharmacokinetics, pharmacodynamics, differences in its actions within mesolimbic reward circuity compared to other opioids, and the possibility of differential molecular and cellular receptor interactions that contribute to its selective effects. We will also discuss marketing strategies and drug difference that likely contributes to the oxycodone opioid use disorders and addiction.

Evaluation of the impact of abuse deterring agents on the physicochemical factors of tramadol-loaded tablet and the definition of new abuse deterrent index

In the design of abuse-deterrent formulations (ADFs), pharmaceutical strategies that do not modify the physical and chemical properties of opioid dosage forms should be investigated. Among these, four major drug abusing factors, including particle size by physical modification, swellability, dissolution rate, and solvent extraction, were mainly characterized for evaluating abuse deterrence of narcotics. Tramadol hydrochloride (TMD) was chosen as a model drug. In this study, the frequently used eight generally recognized as safe (GRAS)-listed pharmaceutical excipients, including polyvinyl alcohol (PVA), hydroxypropyl methylcellulose (HPMC 4,000, HPMC 100,000), xanthan gum (XG), cellulose acetate (CA), polyethylene oxide (PEO), carbomer 940 NF, and Compritol® 888 ATO, were selected as abuse deterring agents and used to prepare TMD-loaded tablet. A new abuse-deterrent index (ADI) for compressed TMD-loaded tablets was originally defined and considered as an index of drug abuse deterrence, based on the assumption that it was proportional to particle size and swellability but inversely proportional to dissolution and solvent extraction rates after assigning the categorized five scale scores (one to five) to the four experimental data. The resulting ADI of the selected eight abuse deterring agents in deionized water was given in decreasing order: HPMC 4000 > carbomer 940 > Compritol® 888 ATO > XG > PVA > HPMC 100,000 > PEO, and CA while in 40% hydro-alcoholic solution in the decreasing order: carbomer 940 > HPMC 4,000 ≒ XG > PVA > HPMC 100,000 > PEO > Compritol® 888 ATO > CA. Interestingly, the HPMC 4,000 and carbomer 940 showed the highest ADI and gave drug abuse deterrent potential. This study could provide a pharmaceutical strategy that utilizes a variety of abuse-deterring agents and resist to extraction solvents in designing drug abuse-deterrent formulations and establishing their standard guidelines for regulatory authorities.

Long-term Safety and Tolerability of NKTR-181 in Patients with Moderate to Severe Chronic Low Back Pain or Chronic Noncancer Pain: A Phase 3 Multicenter, Open-Label, 52-Week Study (SUMMIT-08 LTS)

OBJECTIVE

To evaluate the long-term safety of NKTR-181, a novel mu-opioid receptor agonist that may have reduced human abuse potential, in patients with moderate to severe chronic low back pain (CLBP) or other chronic noncancer pain (CNP).

DESIGN

Uncontrolled, multicenter, open-label, long-term study of NKTR-181 comprised of three periods: screening (≤21 days), treatment (52 weeks), and safety follow-up (∼14 days after the last dose of NKTR-181).

SETTING

Multicenter, long-term clinical research study.

METHODS

NKTR-181 administered at doses of 100-600 mg twice daily (BID) was evaluated in opioid-naïve and opioid-experienced patients. Patients were enrolled de novo or following completion of the randomized, placebo-controlled phase 3 efficacy study (SUMMIT-07). Safety assessments included adverse event documentation, measurements of opioid withdrawal, and clinical laboratory tests. Effectiveness was assessed using the modified Brief Pain Inventory Short Form (mBPI-SF).

RESULTS

The study enrolled 638 patients. The most frequently reported treatment-emergent adverse events (TEAEs) were constipation (26%) and nausea (12%). Serious TEAEs, reported in 5% of patients, were deemed by investigators to be unrelated to NKTR-181. There were no deaths or reported cases of respiratory depression. A sustained reduction in mBPI-SF pain intensity and pain interference from baseline to study termination was observed throughout treatment. Only 2% of patients discontinued NKTR-181 due to lack of efficacy, and 11% discontinued due to treatment-related AEs. NKTR-181 doses of up to 600 mg BID were generally well tolerated, and patients experienced low rates of opioid-related adverse events.

CONCLUSIONS

The study results support the premise that NKTR-181 is a safe and effective option for patients with moderate to severe CLBP or CNP.

Factors mediating pain-related risk for opioid use disorder

Pain is a complex experience with far-reaching organismal influences ranging from biological factors to those that are psychological and social. Such influences can serve as pain-related risk factors that represent susceptibilities to opioid use disorder. This review evaluates various pain-related risk factors to form a consensus on those that facilitate opioid abuse. Epidemiological findings represent a high degree of co-occurrence between chronic pain and opioid use disorder that is, in part, driven by an increase in the availability of opioid analgesics and the diversion of their use in a non-medical context. Brain imaging studies in individuals with chronic pain that use/abuse opioids suggest abuse-related mechanisms that are rooted within mesocorticolimbic processing. Preclinical studies suggest that pain states have a limited impact on increasing the rewarding effects of opioids. Indeed, many findings indicate a reduction in the rewarding and reinforcing effects of opioids during pain states. An increase in opioid use may be facilitated by an increase in the availability of opioids and a decrease in access to non-opioid reinforcers that require mobility or social interaction. Moreover, chronic pain and substance abuse conditions are known to impair cognitive function, resulting in deficits in attention and decision making that may promote opioid abuse. A better understanding of pain-related risk factors can improve our knowledge in the development of OUD in persons with pain conditions and can help identify appropriate treatment strategies. This article is part of the special issue on 'Vulnerabilities to Substance Abuse.'.

Abuse-Deterrent Opioid Formulations and the Opioid Crisis: A Pharmacist's Perspective

BACKGROUND

For over 20 years, the United States has suffered the detrimental effects of an opioid epidemic. Extended-release opioid products are particularly prone to abuse due to the high amount of opioid present. By bypassing the controlled-release mechanisms and nonoral administration, individuals experience intense and dangerous "highs." Abuse-deterrent opioid formulations have been recommended as a potential solution to the crisis, but widespread utilization has been stunted and their role in therapy remains unclear owing to limited real-world efficacy data and affordability issues. This review discusses abuse-deterrent opioid formulations, the mechanisms and data underlying available products, and a pharmacist's perspective of their role in the opioid crisis.

METHODS

The authors reviewed PubMed, MEDLINE, and Google Scholar electronic databases for premarketing and postmarketing studies on OxyContin, Xtampza ER, and Hysingla ER.

RESULTS

Studies showed lower rates of abuse (19% reduction), opioid use disorder (27%), overdose (34%), and fatalities (85%) with the reformulated OxyContin when compared with the original product and comparator opioids. However, these studies revealed the potential for bypassing abuse-deterrent mechanisms and diverting abuse to other drugs. Postmarketing studies are unavailable for Xtampza ER or Hysingla ER, although premarketing studies suggested that some controlled-release properties persist when the product is manipulated, indicating that abuse may be more difficult and less rewarding.

CONCLUSIONS

Abuse-deterrent opioid products may lead to reductions in abuse, overdose, and overdose fatalities. However, cost, loopholes in deterrence mechanism, and possible diversion to other substances hinder their role in the opioid crisis. Multiple approaches must be used to improve opioid safety, and further postmarketing and real-world analyses should be performed on available opioid formulations to assess their impact on abuse-related adverse events.

Analgesic opioid use disorders in patients with chronic non-cancer pain: A holistic approach for tailored management

Chronic pain is a major public health issue that frequently leads to analgesic opioid prescriptions. These prescriptions could cause addiction issues in high-risk patients with associated comorbidities, especially those of a psychiatric, addictive, and social nature. Pain management in dependent patients is complex and is yet to be established. By combining the views of professionals from various specialties, we conducted an integrative review on this scope. This methodology synthesizes knowledge and results of significant practical studies to provide a narrative overview of the literature. The main results consisted in first proposing definitions that could allow shared vocabulary among health professionals regardless of their specialties. Next, a discussion was conducted around the main strategies for managing prescription opioid dependence, as well as pain in the context of opioid dependence and associated comorbidities. As a conclusion, we proposed to define the contours of holistic management by outlining the main guidelines for creating a multidisciplinary care framework for multi-comorbid patients with chronic pathologies.

An evaluation of online discussion relating to nonmedical use of prescription opioids within the UK

AIM

To identify and describe the nature of online discussion relating to prescription opioids within the UK.

METHODS

We performed analysis of posts originating in the UK related to buprenorphine, hydrocodone, oxycodone and tramadol using Social Studio, a web-monitoring platform. The study included posts published between January 2014 and December 2016. The data were cleaned to produce a final dataset consisting only of substantive mentions, which were then categorised by defined themes.

RESULTS

The final dataset included a total of 17 361 substantive mentions (2936 buprenorphine, 2894 hydrocodone, 3826 oxycodone and 7705 tramadol). The most common theme for all 4 drugs was sharing experience or opinion comprising over 90% of mentions for each drug, while discussion related to polysubstance use was present in >1/4 of mentions across drug substances. Mentions related to diversion were more common for hydrocodone and oxycodone (8.1% [6.3-10.1 95% confidence interval] and 7.8% [6.5-9.2], respectively) than buprenorphine or tramadol (4.1 and 3.9% [3.5-4.3], respectively).

CONCLUSION

This investigation shows that there is substantial online discussion relating to a variety of nonmedical use (NMU) behaviours of prescription opioids within the UK, including for hydrocodone, which is not medically available. Web monitoring provides useful data and merits future investigation; this could include expansion to other categories of drugs and a more in-depth analysis of motivations behind NMU, both of which could add timely evidence regarding the current situation in the UK and help inform public health interventions for NMU of prescription drugs.

Extended release pellets prepared by hot melt extrusion technique for abuse deterrent potential: Category-1 in-vitro evaluation

The objective of the present study was to develop extended-release (ER) hot-melt extruded (HME) abuse-deterrent pellets of acetaminophen, a model drug, by utilizing high molecular weight polyethylene oxide (PEO) and gelling agents (xanthan gum, guar gum, and gellan gum). The HME pellets were evaluated for their abuse-deterrence (AD) potential by Category-1 laboratory in-vitro evaluation parameters, including particle size reduction (PSR), small volume extraction, dissolution, viscosity, syringeability, and injectability. Further, the pellets were investigated for resistance to physical (crushing) and thermal (oven and microwave) manipulation to evaluate the strength of the AD properties. Physical manipulation studies demonstrated that the pellets were intact, extremely hard, and resistant to PSR and manipulation to bypass ER properties. Dissolution of all intact and physically manipulated pellets led to complete drug release within 8 h, and resistance to dose-dumping in 40% ethanol was observed. The drug extraction was <50% in 10 mL of ingestible and non-ingestible solvents under static, agitation, and thermal manipulation conditions with an incubation time of 30 min. The PEO/xanthan gum-based formulation showed higher viscosity, syringe and injection forces, and lower syringeable volume in all manipulation conditions compared with plain PEO pellets. These findings supported the AD potential of PEO and xanthan gum pellets against intravenous abuse.

Anesthetic and Analgesic Drug Products Advisory Committee Activity and Decisions in the Opioid-crisis Era

The United States Food and Drug Administration is tasked with ensuring the efficacy and safety of medications marketed in the United States. One of their primary responsibilities is to approve the entry of new drugs into the marketplace, based on the drug’s perceived benefit–risk relationship. The Anesthetic and Analgesic Drug Product Advisory Committee is composed of experts in anesthesiology, pain management, and biostatistics, as well as consumer and industry representatives, who meet several times annually to review new anesthetic-related drugs, those seeking new indications, and nearly every opioid-related application for approval. The following report describes noteworthy activities of this committee since 2017, as it has grappled, along with the Food and Drug Administration, to balance the benefit–risk relationships for individual patients along with the overarching public health implications of bringing additional opioids to market. All anesthesia advisory committee meetings since 2017 will be described, and six will be highlighted, each with representative considerations for potential new opioid formulations or local anesthetics.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Replacement of current opioid drugs focusing on MOR-related strategies

The scarcity and limited risk/benefit ratio of painkillers available on the market, in addition to the opioid crisis, warrant reflection on new innovation strategies. The pharmacopoeia of analgesics is based on products that are often old and derived from clinical empiricism, with limited efficacy or spectrum of action, or resulting in an unsatisfactory tolerability profile. Although they are reference analgesics for nociceptive pain, opioids are subject to the same criticism. The use of opium as an analgesic is historical. Morphine was synthesized at the beginning of the 19th century. The efficacy of opioids is limited in certain painful contexts and these drugs can induce potentially serious and fatal adverse effects. The current North American opioid crisis, with an ever-rising number of deaths by opioid overdose, is a tragic illustration of this. It is therefore legitimate to develop research into molecules likely to maintain or increase opioid efficacy while improving their tolerability. Several avenues are being explored including targeting of the mu opioid receptor (MOR) splice variants, developing biased agonists or targeting of other receptors such as heteromers with MOR. Ion channels acting as MOR effectors, are also targeted in order to offer compounds without MOR-dependent adverse effects. Another route is to develop opioid analgesics with peripheral action or limited central nervous system (CNS) access. Finally, endogenous opioids used as drugs or compounds that modify the metabolism of endogenous opioids (Dual ENKephalinase Inhibitors) are being developed. The aim of the present review is to present these various targets/strategies with reference to current indications for opioids, concerns about their widespread use, particularly in chronic non-cancer pains, and ways of limiting the risk of opioid abuse and misuse.

Development of Abuse-Deterrent Formulations Using Sucrose Acetate Isobutyrate

The objective of the present investigation was to understand the effect of sucrose acetate isobutyrate (SAIB) on abuse-deterrent properties (ADPs) of abuse-deterrent formulations (ADFs) based on Polyox™. SAIB would enhance ADPs of Polyox™-based formulations due to its glassy liquid and hydrophobic properties. Formulations were prepared by granulation followed by compression and heat curing at 90°C. The formulations were evaluated for surface morphology, hardness, manipulation in coffee grinder, particle size distribution, drug (pseudoephedrine hydrochloride) extraction in water, alcohol, 0.1 N HCl, 0.1 N NaOH at room temperature and elevated temperature using microwave and oven, syringeability and injectability, and dissolution. The heat curing of formulations significantly increased the hardness (> 490 N). Addition of SAIB imparted elasticity to formulations and decreased brittleness as indicated by lower values of work done and gradient compared to control formulations. After grinding, about 7.7-25.6% of the powder remained on the sieve (1 mm pore opening), D₉₀ was 53.1-136.7 μm more, and Q (fraction < 500 μm) was 17.8-40.7% less in SAIB-based formulations compared to control formulations. Drug extraction between control and test intact formulations was similar. However, drug extraction was 23.9-42.5% (water), 20.6-26.1% (0.1 N HCl), and 37.4-50.6% (0.1 N NaOH) less in SAIB-based powder cured and uncured formulations compared to control formulations. Dissolution varied from 65.6 ± 4.2 to 97.6 ± 4.0% in 9 h from the formulations. In conclusion, addition of SAIB to Polyox™-based ADFs has synergistic effect on ADPs. This would further decrease potential of drug abuse/misuse by various routes.

Pharmacokinetic and pharmacodynamic considerations in developing a response to the opioid epidemic

Introduction: Opioids continue to be used widely for pain management. Widespread availability of prescription opioids has led to opioid abuse and addiction. Besides steps to reduce inappropriate prescribing, exploiting opioid pharmacology to make their use safer is important.Areas covered: This article discusses the pathology and factors underlying opioid abuse. Pharmacokinetic and pharmacodynamic properties affecting abuse liability of commonly abused opioids have been highlighted. These properties inform the development of ideal abuse deterrent products. Mechanisms and cost-effectiveness of available abuse deterrent products have been reviewed in addition to the pharmacology of medications used to treat addiction.Expert opinion: The opioid crisis presents unique challenges to managing pain effectively given the limited repertoire of strong analgesics. The 5-point strategy to combat the opioid crisis calls for better preventive, treatment, and recovery services, better data, better pain management, better availability of overdose-reversing drugs and better research. There is an urgent need to decrease the cost of abuse deterrent opioids which deters their cost-effectiveness. In addition, discovery of novel analgesics, further insight into central and peripheral pain mechanisms, understanding genomic risk profiles for efficient targeted efforts, and education will be key to winning this fight against the opioid crisis.

Polysubstance Use: A Broader Understanding of Substance Use During the Opioid Crisis

Objectives. To understand important changes in co-occurring opioid and nonopioid drug use (i.e., polysubstance use) within the opioid epidemic in the United States.Methods. We analyzed survey data on the past month co-use of prescription and illicit opioids and 12 nonopioid psychoactive drug classes from a national sample of 15 741 persons entering treatment of opioid use disorder.Results. Past-month illicit opioid use increased from 44.8% in 2011 to 70.1% in 2018, while the use of prescription opioids alone dropped from 55.2% to 29.9%, yet overall remained high (94.5% to 85.2%). Past-month use of at least 1 nonopioid drug occurred in nearly all participants (> 90%), with significant increases in methamphetamine (+85%) and decreases across nonopioid prescription drug classes (range: -40% to -68%).Conclusions. Viewing opioid trends in a "silo" ignores the fact not only that polysubstance use is ubiquitous among those with opioid use disorder but also that significant changes in polysubstance use should be monitored alongside opioid trends.Public Health Implications. Treatment, prevention, and policymaking must address not only the supply and demand of a singular drug class but also the global nature of substance use overall.

The prescription opioid conundrum: 21st century solutions to a millennia-long problem

Health-care professionals are faced with a daunting task: balancing appropriate care for chronic pain with their responsibility to keep patients and others safe from treatment-related harm. Whereas opioids have historically been considered an effective tool in the analgesic armamentarium, the rise of opioid abuse has caused the pendulum to swing away from prescribing opioids to an emphasis on safety. This paradigm shift risks neglecting the very real consequences of untreated/undertreated pain. Using data from the medical literature, this review examines influences on the real and perceived benefit-to-risk ratio for opioids and provides clinicians with a practical approach to prescribing opioids that minimizes the risk for abuse/misuse. There is appreciable clinical trial and observational evidence of efficacy/effectiveness with opioids used for pain management over the short or long term when considered in the context of pharmacologic alternatives. Enhancing the relative safety and minimizing the risk for abuse/misuse may be achieved through proactive prescription practices that include careful patient selection, risk assessment, individualized and multimodal treatment plans with established goals, initiating opioid treatment cautiously with an exit plan in place, ongoing assessments of response to therapy, and routine patient monitoring. Additionally, prescribing opioids with a lower potential for abuse or misuse (e.g. abuse-deterrent formulations) may provide a benefit. Using a pragmatic approach to prescribing practices, we postulate that the balance between benefit and risk can be favorable for opioid therapy in select patients, even for long-term treatment of chronic pain.

Combining opioids and non-opioids for pain management: Current status

Pain remains a global health challenge. For decades, clinicians have been primarily relying on μ-opioid receptor (MOR) agonists and nonsteroidal anti-inflammatory drugs (NSAIDs) for pain management. MOR agonists remain the most efficacious analgesics available; however, adverse effects related to MOR agonists use are severe which often lead to forced drug discontinuation and inadequate pain relief. The recent opioid overdose epidemic urges the development of safer analgesics. Combination therapy is a well-established clinical pharmacotherapeutic strategy for the treatment of various clinical disorders. The combination of MOR agonists with non-MOR agonists may increase the analgesic potency of MOR agonists, reduce the development of tolerance and dependence, reduce the diversion and abuse, overdose, and reduce other clinically significant side effects associated with prolonged opioid use such as constipation. Overall, the combination therapy approach could substantially improve the therapeutic profile of MOR agonists. This review summarizes some recent developments in this field. This article is part of the Special Issue entitled 'New Vistas in Opioid Pharmacology'.

Causal inference for evaluating prescription opioid abuse using trend-in-trend design

PURPOSE

One response to the opioid crisis in the United States has been the development of opioid analgesics with properties intended to reduce non-oral use. Previous evaluations of abuse in the community have relied on population averaged interrupted time series Poisson models with utilization offsets. However, competing interventions and secular trends complicate interpretation of time-series analyses. An alternative research design, trend-in-trend, accounts for heterogeneity in per capita opioid dispensing and unmeasured time-varying confounding, which provides a causal evaluation, provided that underlying assumptions are met.

METHODS

Trend-in-trend can be modeled using a logistic regression framework. In logistic regression, exposure was any product-specific outpatient dispensing by three-digit ZIP code and calendar quarter, for 22 opioids. The outcome was any product-specific abuse case ascertained from poison centers and drug treatment programs, covering 94% of the US population, between July 2009 and December 2016. Product-specific odds ratios compared places without dispensing with places with any dispensing; the causal contrast represents the odds of product-specific abuse in the community given exposure.

RESULTS

Dispensing of new and low-volume opioids varied considerably across the country, with no region showing high of all products. Of 22 opioids analyzed, the three with approved labeling as intended to deter abuse ranked near the lowest in both absolute (population-adjusted rates: 1.7, 0.9, and 8.2 per million people per quarter, respectively) and relative measures (trend-in-trend ORs: 1.96, 1.79, 1.69, respectively).

CONCLUSIONS

Postmarketing studies of prescription opioid abuse may benefit by evolving from unadjusted surveillance rates to a causal inference approach.

Pain Management for Patients With Advanced Cancer in the Opioid Epidemic Era

Use of opioids for the treatment of pain is necessary for the majority of patients with advanced cancer, however its use has become challenging in the face of the opioid epidemic and the emerging evidence that patients with cancer are also at risk for nonmedical opioid use. This article proposes an assessment and treatment plan that incorporates universal screening with monitoring for all patients with cancer who are considered for opioid treatment to assess their risk for opioid misuse and harm. Timely identification with appropriate management, including referral of at-risk patients, will allow oncology professionals to optimize the risk-to-benefit and support the safe use of opioids for patients with cancer.

Determining Abuse Deterrence Performance of Poly (ethylene oxide) Using a Factorial Design

Purpose: The purpose of this study was to determine the effects of thermal processing and antioxidant formulation variables on the abuse deterrence performance of a high molecular weight poly(ethylene oxide) (PEO) polymer.

Methods: A 2⁴ factorial design with one categorical factor (antioxidant type) and three continuous factors (curing time, curing temperature, % antioxidant) was used. Abuse deterrence performance was evaluated using solution viscosity, surface melting temperature, and mechanical strength. Thermal degradation of PEO powders before compaction was also studied using DSC, FTIR spectroscopy, and viscosity analysis.

Results: Our results showed that curing temperature and type of antioxidant can significantly affect the deterrence performance of PEO. The main effect plot for viscosity shows the most prominent factors affecting viscosity are curing temperature and type of antioxidant. However, curvature in the linear model obtained was not sufficient to completely describe the behavior. For surface melting temperature, butylated hydroxytoluene was associated with higher surface melting temperatures compared to ascorbic acid. Additionally, higher percent of antioxidant resulted in higher melting temperature. Particle size distribution to indicate mechanical strength showed no significant effects of tested factors. This suggests that comminution method has more prominent effect on tablet fragment size than the formulation and processing factors studied.

Conclusion: While heat confers the mechanical strength to the polymer, it can diminish its physical stability and solution state viscosity. The experimental studies showed that prolonged exposure to high temperatures, even in the presence of antioxidants, can severely hamper polymer deterrence performance in both solid and solution states.