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Anesthesiology Oct 2020The 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... (Review)
Review
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.
Topics: Advisory Committees; Analgesics; Analgesics, Opioid; Anesthetics; Congresses as Topic; Decision Making; Delayed-Action Preparations; Drug Approval; Humans; Opioid-Related Disorders; Oxymorphone; Spiro Compounds; Thiophenes; United States
PubMed: 32773684
DOI: 10.1097/ALN.0000000000003485 -
Frontiers in Pharmacology 2023The United States (US) ranks high, nationally, in opioid consumption. The ongoing increase in the misuse and mortality amid the opioid epidemic has been contributing to...
The United States (US) ranks high, nationally, in opioid consumption. The ongoing increase in the misuse and mortality amid the opioid epidemic has been contributing to its rising cost. The worsening health and economic impact of opioid use disorder in the US warrants further attention. We, therefore, assessed commonly prescribed opioids to determine the opioids that were over-represented versus under-represented for adverse drug events (ADEs) to better understand their distribution patterns using the Food and Drug Administration's Adverse Event Reporting System (FAERS) while correcting for distribution using the Drug Enforcement Administration's Automation of Reports and Consolidated Orders System (ARCOS). Comparing the ratio of the percentage of adverse drug events as reported by the FAERS relative to the percentage of distribution as reported by the ARCOS database is a novel approach to evaluate post-marketing safety surveillance and may inform healthcare policies and providers to better regulate the use of these opioids. We analyzed the adverse events for 11 prescription opioids, when correcting for distribution, and their ratios for three periods, 2006-2010, 2011-2016, and 2017-2021, in the US. The opioids include buprenorphine, codeine, fentanyl, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, oxymorphone, and tapentadol. Oral morphine milligram equivalents (MMEs) were calculated by conversions relative to morphine. The relative ADEs of the selected opioids, opioid distributions, and ADEs relative to distribution ratios were analyzed for the 11 opioids. Oxycodone, fentanyl, and morphine accounted for over half of the total number of ADEs ( = 667,969), while meperidine accounted for less than 1%. Opioid distributions were relatively constant over time, with methadone repeatedly accounting for the largest proportions. Many ADE-to-opioid distribution ratios increased over time, with meperidine (60.6), oxymorphone (11.1), tapentadol (10.3), and hydromorphone (7.9) being the most over-represented for ADEs in the most recent period. Methadone was under-represented (<0.20) in all the three periods. The use of the FAERS with the ARCOS provides insights into dynamic changes in ADEs of the selected opioids in the US. There is further need to monitor and address the ADEs of these drugs.
PubMed: 37033633
DOI: 10.3389/fphar.2023.1163976 -
JMIR Public Health and Surveillance Jun 2020Between 2016 and 2017, the national mortality rate involving opioids continued its escalation; opioid deaths rose from 42,249 to 47,600, bringing the public health...
BACKGROUND
Between 2016 and 2017, the national mortality rate involving opioids continued its escalation; opioid deaths rose from 42,249 to 47,600, bringing the public health crisis to a new height. Considering that 69% of adults in the United States use online social media sites, a resource that builds a more complete understanding of prescription drug misuse and abuse could supplement traditional surveillance instruments. The Food and Drug Administration has identified 5 key risks and consequences of opioid drugs-misuse, abuse, addiction, overdose, and death. Identifying posts that discuss these key risks could lead to novel information that is not typically captured by traditional surveillance systems.
OBJECTIVE
The goal of this study was to describe the trends of online posts (frequency over time) involving abuse, misuse, addiction, overdose, and death in the United States and to describe the types of websites that host these discussions. Internet posts that mentioned fentanyl, hydrocodone, oxycodone, or oxymorphone were examined.
METHODS
Posts that did not refer to personal experiences were removed, after which 3.1 million posts remained. A stratified sample of 61,000 was selected. Unstructured data were classified into 5 key risks by manually coding for key outcomes of misuse, abuse, addiction, overdose, and death. Sampling probabilities of the coded posts were used to estimate the total post volume for each key risk.
RESULTS
Addiction and misuse were the two most commonly discussed key risks for hydrocodone, oxycodone, and oxymorphone. For fentanyl, overdose and death were the most discussed key risks. Fentanyl had the highest estimated number of misuse-, overdose-, and death-related mentions (41,808, 42,659, and 94,169, respectively). Oxycodone had the highest estimated number of abuse- and addiction-related mentions (3548 and 12,679, respectively). The estimated volume of online posts for fentanyl increased by more than 10-fold in late 2017 and 2018. The odds of discussing fentanyl overdose (odds ratios [OR] 4.32, 95% CI 2.43-7.66) and death (OR 5.05, 95% CI 3.10-8.21) were higher for social media, while the odds of discussing fentanyl abuse (OR 0.10, 95% CI 0.04-0.22) and addiction (OR 0.24, 95% CI 0.15-0.38) were higher for blogs and forums.
CONCLUSIONS
Of the 5 FDA-defined key risks, fentanyl overdose and death has dominated discussion in recent years, while discussion of oxycodone, hydrocodone, and oxymorphone has decreased. As drug-related deaths continue to increase, an understanding of the motivations, circumstances, and consequences of drug abuse would assist in developing policy responses. Furthermore, content was notably different based on media origin, and studies that exclusively use either social media sites (such as Twitter) or blogs and forums could miss important content. This study sets out sustainable, ongoing methodology for surveilling internet postings regarding these drugs.
Topics: Adult; Analgesics, Opioid; Epidemiology; Female; Fentanyl; Humans; Hydrocodone; Male; Middle Aged; Odds Ratio; Opioid Epidemic; Oxycodone; Oxymorphone; Population Surveillance; Social Media; Substance-Related Disorders; United States
PubMed: 32597786
DOI: 10.2196/17073 -
Clinical Pharmacokinetics Jul 2023Up to 90% of patients with castration-resistant prostate cancer (CRPC) will develop symptomatic bone metastases requiring pain medication, with opioids being the...
BACKGROUND AND OBJECTIVE
Up to 90% of patients with castration-resistant prostate cancer (CRPC) will develop symptomatic bone metastases requiring pain medication, with opioids being the mainstay of therapy in treating moderate and severe pain. Enzalutamide is an androgen receptor antagonist for the treatment of CRPC and a strong inducer of cytochrome P450 (CYP)3A4. Hereby, enzalutamide potentially reduces the exposure of oxycodone, an opioid metabolized by CYP3A4 and CYP2D6. Our objective was to evaluate the potential drug-drug interaction of enzalutamide and oxycodone.
METHODS
A prospective, nonrandomized, open-label, two-arm parallel study was performed. All patients received a single dose of 15 mg normal-release oxycodone. Patients in the enzalutamide arm (ENZ-arm) received enzalutamide 160 mg once daily. Plasma concentrations of oxycodone and its metabolites were quantified using a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS) method.
RESULTS
Twenty-six patients (13 ENZ-arm; 13 control arm) were enrolled in the study. Enzalutamide decreased the mean AUC and C of oxycodone with, respectively, 44.7% (p < 0.001) and 35.5% (p = 0.004) compared with the control arm. The AUC and C of the active metabolite oxymorphone were 74.2% (p < 0.001) and 56.0% (p = 0.001) lower in the ENZ-arm compared with the control arm. In contrast, AUC and C of the inactive metabolites noroxycodone and noroxymorphone were significantly increased by enzalutamide.
CONCLUSION
Co-administration of enzalutamide significantly reduced exposure to oxycodone and its active metabolite oxymorphone in men with prostate cancer. This should be taken into account when prescribing enzalutamide combined with oxycodone.
Topics: Male; Humans; Oxycodone; Oxymorphone; Chromatography, Liquid; Prospective Studies; Prostatic Neoplasms, Castration-Resistant; Tandem Mass Spectrometry; Analgesics, Opioid; Pain
PubMed: 37162620
DOI: 10.1007/s40262-023-01255-1 -
British Journal of Clinical Pharmacology Apr 2021Prescription drug misuse in the USA increased during the 1990s to 2010. The epidemic stimulated the need new analytical strategies and techniques to understand the...
AIMS
Prescription drug misuse in the USA increased during the 1990s to 2010. The epidemic stimulated the need new analytical strategies and techniques to understand the medications involved, user characteristics and other factors needed to address the epidemic.
METHODS
A strategy of mosaic surveillance has evolved. Using real world evidence, the goal is to paint a more complete profile of a drug's real world misuse using triangulation-integrating results from multiple sources, where each approach has unrelated sources of bias.
RESULTS
Research findings have been remarkably consistent across multiple data sources. The most commonly misused opioid medications: hydrocodone = oxycodone > methadone = buprenorphine = tramadol = fentanyl (prescription form) > morphine > hydromorphone = oxymorphone > tapentadol. This rank order is similar to the number of prescriptions dispensed for each product in the USA. In the USA, prescription opioid misuse started to decrease about 2011. Typically, multiple drugs are misused together, particularly in lethal cases. Immediate release formulations are more commonly misused than extended release formulations. The introduction of tamper resistant formulations to resist crushing were followed by a decrease in misuse of those products.
CONCLUSIONS
The rapid expansion of opioid prescribing was accompanied by increasing misuse and mortality. Interventions such as prescription drug monitoring programmes, increased law enforcement and abuse deterrent formulations have been followed by decreases in misuse of most opioid analgesics.
Topics: Analgesics, Opioid; Humans; Opioid-Related Disorders; Oxycodone; Practice Patterns, Physicians'; Prescription Drug Misuse
PubMed: 33606888
DOI: 10.1111/bcp.14791 -
European Journal of Pharmaceutical... Mar 2024Oxycodone is one of the most commonly used opioids to treat moderate to severe pain. It is metabolized mainly by CYP3A4 and CYP2D6, while only a small fraction of the...
Exploring the impact of CYP2D6 and UGT2B7 gene-drug interactions, and CYP-mediated DDI on oxycodone and oxymorphone pharmacokinetics using physiologically-based pharmacokinetic modeling and simulation.
Oxycodone is one of the most commonly used opioids to treat moderate to severe pain. It is metabolized mainly by CYP3A4 and CYP2D6, while only a small fraction of the dose is excreted unchanged into the urine. Oxymorphone, the metabolite primarily formed by CYP2D6, has a 40- to 60-fold higher mu-opioid receptor affinity than the parent compound. While CYP2D6-mediated gene-drug-interactions (GDIs) and drug-drug interactions (DDIs) are well-studied, they only account for a portion of the variability in oxycodone and oxymorphone exposure. The combined impact of CYP2D6-mediated GDIs and DDIs, CYP3A4-mediated DDIs, and UGT2B7 GDIs is not fully understood yet and hard to study in head-to-head clinical trials given the relatively large number of scenarios. Instead, we propose the use of a physiologically-based pharmacokinetic model that integrates available information on oxycodone's metabolism to characterize and predict the impact of DDIs and GDIs on the exposure of oxycodone and its major, pharmacologically-active metabolite oxymorphone. To this end, we first developed and verified a PBPK model for oxycodone and its metabolites using published clinical data. The verified model was then applied to determine the dose-exposure relationship of oxycodone and oxymorphone stratified by CYP2D6 and UGT2B7 phenotypes respectively, and administered perpetrators of CYP-based drug interactions. Our simulations demonstrate that the combination of CYP2D6 UM and a UGT2B7Y (268) mutation may lead to a 2.3-fold increase in oxymorphone exposure compared to individuals who are phenotyped as CYP2D6 NM / UGT2B7 NM. The extent of oxymorphone exposure increases up to 3.2-fold in individuals concurrently taking CYP3A4 inhibitors, such as ketoconazole. Inhibition of the CYP3A4 pathway results in a relative increase in the partial metabolic clearance of oxycodone to oxymorphone. Oxymorphone is impacted to a higher extent by GDIs and DDIs than oxycodone. We predict oxymorphone exposure to be highest in CYP2D6 UMs/UGT2B7 PMs in the presence of ketoconazole (strong CYP3A4 index inhibitor) and lowest in CYP2D6 PMs/UGT2B7 NMs in the presence of rifampicin (strong CYP3A4 index inducer) covering a 55-fold exposure range.
Topics: Humans; Oxycodone; Oxymorphone; Cytochrome P-450 CYP2D6; Ketoconazole; Cytochrome P-450 CYP3A; Drug Interactions; Cytochrome P-450 CYP3A Inhibitors; Cytochrome P-450 CYP3A Inducers; Guanine Nucleotide Dissociation Inhibitors; Glucuronosyltransferase
PubMed: 38171419
DOI: 10.1016/j.ejps.2023.106689 -
Pharmacy (Basel, Switzerland) Jan 2024The United States (US) opioid epidemic is a persistent and pervasive public health emergency that claims the lives of over 80,000 Americans per year as of 2021. There...
The United States (US) opioid epidemic is a persistent and pervasive public health emergency that claims the lives of over 80,000 Americans per year as of 2021. There have been sustained efforts to reverse this crisis over the past decade, including a number of measures designed to decrease the use of prescription opioids for the treatment of pain. This study analyzed the changes in federal production quotas for prescription opioids and the distribution of prescription opioids for pain and identified state-level differences between 2010 and 2019. Data (in grams) on opioid production quotas and distribution (from manufacturer to hospitals, retail pharmacies, practitioners, and teaching institutions) of 10 prescription opioids (codeine, fentanyl, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, oxymorphone, and tapentadol) for 2010 to 2019 were obtained from the US Drug Enforcement Administration. Amounts of each opioid were converted from grams to morphine milligram equivalent (MME), and the per capita distribution by state was calculated using population estimates. Total opioid production quotas increased substantially from 2010 to 2013 before decreasing by 41.5% from 2013 (87.6 MME metric tons) to 2019 (51.3). The peak year for distribution of all 10 prescription opioids was between 2010 and 2013, except for codeine (2015). The largest quantities of opioid distribution were observed in Tennessee (520.70 MME per person) and Delaware (251.45) in 2011 and 2019. There was a 52.0% overall decrease in opioid distribution per capita from 2010 to 2019, with the largest decrease in Florida (-61.6%) and the smallest in Texas (-18.6%). Southern states had the highest per capita distribution for eight of the ten opioids in 2019. The highest to lowest state ratio of total opioid distribution, corrected for population, decreased from 5.25 in 2011 to 2.78 in 2019. The mean 95th/5th ratio was relatively consistent in 2011 (4.78 ± 0.70) relative to 2019 (5.64 ± 0.98). This study found a sustained decline in the distribution of ten prescription opioids during the last five years. Distribution was non-homogeneous at the state level. Analysis of state-level differences revealed a fivefold difference in the 95th:5th percentile ratio between states, which has remained unchanged over the past decade. Production quotas did not correspond with the distribution, particularly in the 2010-2016 period. Future research, focused on identifying factors contributing to the observed regional variability in opioid distribution, could prove valuable to understanding and potentially remediating the pronounced disparities in prescription opioid-related harms in the US.
PubMed: 38251408
DOI: 10.3390/pharmacy12010014 -
Biological Psychiatry Dec 2023Mu opioid receptors (MORs) are key for reward processing, mostly studied in dopaminergic pathways. MORs are also expressed in the dorsal raphe nucleus (DRN), which is...
BACKGROUND
Mu opioid receptors (MORs) are key for reward processing, mostly studied in dopaminergic pathways. MORs are also expressed in the dorsal raphe nucleus (DRN), which is central for the modulation of reward and mood, but MOR function in the DRN remains underexplored. Here, we investigated whether MOR-expressing neurons of the DRN (DRN-MOR neurons) participate in reward and emotional responses.
METHODS
We characterized DRN-MOR neurons anatomically using immunohistochemistry and functionally using fiber photometry in responses to morphine and rewarding/aversive stimuli. We tested the effect of opioid uncaging on the DRN on place conditioning. We examined the effect of DRN-MOR neuron optostimulation on positive reinforcement and mood-related behaviors. We mapped their projections and selected DRN-MOR neurons projecting to the lateral hypothalamus for a similar optogenetic experimentation.
RESULTS
DRN-MOR neurons form a heterogeneous neuronal population essentially composed of GABAergic (gamma-aminobutyric acidergic) and glutamatergic neurons. Calcium activity of DRN-MOR neurons was inhibited by rewarding stimuli and morphine. Local photo-uncaging of oxymorphone in the DRN produced conditioned place preference. DRN-MOR neuron optostimulation triggered real-time place preference and was self-administered, promoted social preference, and reduced anxiety and passive coping. Finally, specific optostimulation of DRN-MOR neurons projecting to the lateral hypothalamus recapitulated the reinforcing effects of total DRN-MOR neuron stimulation.
CONCLUSIONS
Our data show that DRN-MOR neurons respond to rewarding stimuli and that their optoactivation has reinforcing effects and promotes positive emotional responses, an activity which is partially mediated by their projections to the lateral hypothalamus. Our study also suggests a complex regulation of DRN activity by MOR opioids, involving mixed inhibition/activation mechanisms that fine-tune DRN function.
Topics: Dorsal Raphe Nucleus; Receptors, Opioid, mu; Neurons; Morphine; Analgesics, Opioid; Reward
PubMed: 37285896
DOI: 10.1016/j.biopsych.2023.05.019 -
Biochemical Pharmacology Apr 2022Opioids, and numerous centrally active drugs, are metabolized by cytochrome P450 2D (CYP2D). There are sex and estrous cycle differences in brain oxycodone analgesia....
Opioids, and numerous centrally active drugs, are metabolized by cytochrome P450 2D (CYP2D). There are sex and estrous cycle differences in brain oxycodone analgesia. Here we investigated the mechanism examining the selective role of CYP2D in the brain on sex, estrous cycle, and hormonal regulation. Propranolol, CYP2D-specific mechanism-based inhibitor, or vehicle was delivered into cerebral ventricles 24 h before administering oxycodone (or oxymorphone, negative control) orally to male and female (in estrus and diestrus) rats. Ovariectomized and sham-operated females received no treatment, estradiol, progesterone or vehicle. Analgesia was measured using tail-flick latency, and brain drug and metabolite concentrations were measured by microdialysis. Data were analyzed by two-way or mixed ANOVA. Following propranolol (versus vehicle) inhibition and oral oxycodone, there were greater increases in brain oxycodone concentrations and analgesia, and greater decreases in brain oxymorphone/oxycodone ratios (an in vivo phenotype of CYP2D in brain) in males and females in estrus, compared to females in diestrus; with no impact on plasma drug concentrations. There was no impact of propranolol pre-treatment, sex, or cycle after oral oxymorphone (non-CYP2D substrate) on brain oxymorphone concentrations or analgesia. There was no impact of propranolol pre-treatment following ovariectomy on brain oxycodone concentrations or analgesia, which was restored in ovariectomized females following estradiol, but not progesterone, treatment. Sex, cycle, and estradiol regulation of CYP2D in brain in turn altered brain oxycodone concentration and response, which may contribute to the large inter-individual variation in response to the numerous centrally acting CYP2D substrate drugs, including opioids.
Topics: Analgesia; Analgesics, Opioid; Animals; Brain; Cytochrome P-450 Enzyme System; Estradiol; Estrous Cycle; Female; Male; Oxycodone; Oxymorphone; Pain; Progesterone; Propranolol; Rats; Rats, Wistar
PubMed: 35143755
DOI: 10.1016/j.bcp.2022.114949 -
Frontiers in Veterinary Science 2019To assess the impact of the human opioid epidemic and associated shortages in drug supply on US general practice veterinarians. Cross-sectional study. Members of the...
To assess the impact of the human opioid epidemic and associated shortages in drug supply on US general practice veterinarians. Cross-sectional study. Members of the Veterinary Information Network (VIN). An electronic survey was used to examine veterinarians' views regarding opioid use in veterinary medicine and the impact of the opioid shortage on the provision of care. The survey was distributed via the VIN data collection portal from October 12-November 6, 2018. 697 veterinarians completed the survey. Most (99.7%) reported using, dispensing or prescribing opioids in veterinary practice. The most commonly used opioids were buprenorphine, tramadol and butorphanol. While most veterinarians (83.3%) reported difficulty in ordering opioids over the last 6 months, this decreased to 59.0% in the last month. The most difficult drugs to obtain were hydromorphone, morphine, injectable fentanyl, and oxymorphone. The reported rate of difficulty in obtaining all these drugs lessened over time. However, the opioid shortage caused significant difficulty in providing appropriate pain management for 41.1% of participants, and affected the ability of 44.8% of respondents to provide optimal anesthesia. Veterinarians' ability to provide opioids for their patients has been impacted by the opioid shortage, with a greater impact on full mu opioid agonists as compared to drugs like butorphanol, buprenorphine, and tramadol. The results confirm the important role of opioid analgesics in the delivery of modern veterinary medicine and highlight the importance of medical health professionals being able to access these critical medications.
PubMed: 31334257
DOI: 10.3389/fvets.2019.00222