Tackling new psychoactive substances through metabolomics: UHPLC-HRMS study on natural and synthetic opioids in male and female murine models.

Novel psychoactive substances (NPS) represent a broad class of drugs new to the illicit market that often allow passing drug-screening tests. They are characterized by a variety of structures, rapid transience on the drug scene and mostly unknown metabolic profiles, thus creating an ever-changing scenario with evolving analytical targets. The present study aims at developing an indirect screening strategy for NPS monitoring, and specifically for new synthetic opioids (NSOs), based on assessing changes in endogenous urinary metabolite levels as a consequence of the systemic response following their intake. The experimental design involved in-vivo mice models: 16 animals of both sex received a single administration of morphine or fentanyl. Urine was collected before and after administration at different time points; the samples were then analysed with an untargeted metabolomics LC-HRMS workflow. According to our results, the intake of opioids resulted in an elevated energy demand, that was more pronounced on male animals, as evidenced by the increase in medium and long chain acylcarnitines levels. It was also shown that opioid administration disrupted the pathways related to catecholamines biosynthesis. The observed alterations were common to both morphine and fentanyl: this evidence indicate that they are not related to the chemical structure of the drug, but rather on the drug class. The proposed strategy may reinforce existing NPS screening approaches, by identifying indirect markers of drug assumption.

Prevalence of abnormal urine drug tests during COVID-19 pandemic in the cancer patient population: retrospective study.

Background: Opioid misuse is a persistent concern, heightened by the COVID-19 pandemic. This study examines the risk factors contributing to elevated rates of abnormal urine drug tests (UDTs) in the cancer pain patient population during COVID-19. Materials & methods: A retrospective chart review of 500 patient encounters involving UDTs at a comprehensive cancer center. Results: Medication adherence rates increase when UDTs are incorporated into a chronic cancer pain management protocol. Higher positive tests for illicit or nonprescribed substances in patients with specific risk factors: current smokers (tobacco), no active cancer and concurrent benzodiazepine use. Conclusion: This research emphasizes the increased risk of opioid misuse during COVID-19 among cancer pain patients with specific risk factors outlined in the results.

This study looked at how the COVID-19 pandemic has affected opioid use among people with cancer-related pain. The researchers checked the records of 500 patients who had had tests to see if they used opioids correctly. They found that when these tests were part of the treatment plan, patients were more likely to take their medicines correctly. However, they also noticed that certain patients, such as those who smoke, do not have active cancer or are taking another type of medication (i.e., benzodiazepines), are more likely to use opioids or other drugs in ways that deviated from the original intention. This study shows that during the pandemic, which continues to exist, it is even more important to watch how these patients use their painkillers and help them avoid misuse.

N-desethyl isotonitazene detected in polydrug users admitted to hospital in Birmingham, United Kingdom.

INTRODUCTION: Nitazenes are potent synthetic opioids and N-desethyl isotonitazene, a metabolite of isotonitazene, has emerged as a drug in its own right. METHODS: This is an observational case series of patients with suspected or declared substance use who were admitted to hospitals in the Sandwell and West Birmingham National Health Service Trust between July and October 2023. All patients were found on toxicological screening to have been exposed to N-desethyl isotonitazene. RESULTS: Twenty presentations involving 19 patients who tested positive for N-desethyl isotonitazene were included in the study. In 19 presentations, multiple substances were detected on toxicological screening. The number of patients testing positive for other substances were: 19 for cocaine and its main metabolite benzoylecgonine, 13 for morphine, 11 for the heroin-specific metabolite 6-monoacetylmorphine, ten for xylazine, eight for gabapentinoids (pregabalin and/or gabapentin), seven for methadone and/or the metabolite, 2-ethylidene-1, 5-dimethyl-3, 3-diphenylpyrrolidine, six for benzodiazepines and five for the synthetic cannabinoid MDMB-4en-PINACA. Only one patient had no other substances detected apart from N-desethyl isotonitazene. This patient presented with coma, miosis, bradypnoea and hypercapnia and responded to naloxone. In this cohort, the median concentration of N-desethyl isotonitazene was 1.53 µg/L (n = 14; range 0.59-5.48) in whole blood and 27.75 µg/L (n = 16; range 0.51-91.53) in urine. DISCUSSION: The majority of the patients in this cohort presented with features typical of an opioid overdose, which is unsurprising as they were all experienced users of diamorphine. Although these features are also consistent with the known effects of N-desethyl isotonitazene, in only one case is it possible to attribute the patient's features to N-desethyl isotonitazene toxicity alone. CONCLUSIONS: This case series highlights the need for toxicovigilance in the illicit drug market as patterns of substance misuse evolve and novel psychoactive substances continue to emerge.

Stimulant use and opioid-related harm in patients on long-term opioids for chronic pain.

BACKGROUND: There is lack of clarity regarding the impact of and optimal clinical response to stimulant use among people prescribed long-term opioid therapy (LTOT) for pain. OBJECTIVE: To determine if a positive urine drug test (UDT) for stimulants was associated with subsequent opioid-related harm or discontinuation of LTOT. DESIGN: Retrospective cohort study. PATIENTS: People living with and without HIV living in a major metropolitan area with public insurance, prescribed LTOT for chronic, non-cancer pain (n=600). MAIN MEASURES: UDT results from January 2012 to June 2019 were evaluated against 1) opioid-related emergency department (ED) visits (oversedation, constipation, infections associated with injecting opioids, and opioid seeking) or death in each 90-day period following a UDT, using logistic regression, and 2) LTOT discontinuation. RESULTS: There were no opioid overdose deaths within 90 days following a stimulant-positive UDT. A stimulant-positive UDT was not statistically significantly associated with opioid-related ED visits within 90 days (adjusted odds ratio [aOR] 1.39; 95% CI=0.88-2.21). Stimulant-positive UDT was independently associated with subsequent discontinuation of LTOT within 90 days (aOR 2.96; 95% CI=2.13 - 4.12). Living with HIV was independently associated with decreased odds of LTOT discontinuation (aOR 0.65; 95% CI 0.43 - 0.99). CONCLUSIONS: Despite no association between a stimulant-positive UDT and subsequent opioid-related harm, there was an association with subsequent LTOT discontinuation, with heterogeneity across clinical groups. Detection of stimulant use should result in a discussion of substance use and risk, rather than reflex LTOT discontinuation.

Advances in fentanyl testing.

Fentanyl is a synthetic opioid that was approved by the FDA in the late 1960s. In the decades since, non-prescription use of fentanyl, its analogs, and structurally unrelated novel synthetic opioids (NSO) has become a worsening public health crisis. There is a clear need for accessible testing for these substances in biological specimens and in apprehended drugs. Immunoassays for fentanyl in urine are available but their performance is restricted to facilities that hold moderate complexity laboratory licenses. Immunoassays for other matrices such as oral fluid (OF), blood, and meconium have been developed but are not widely available. Point of care tests (POCT), such as lateral flow immunoassays or fentanyl test strips (FTS), are widely available but not approved by the FDA for clinical use. All immunoassays are vulnerable to false positive and false negative results. Immunoassays may or may not be able to detect fentanyl analogs and NSOs. Mass spectrometry (MS) can accurately and reliably measure fentanyl and its major metabolite norfentanyl in urine and oral fluid. MS is available at reference laboratories and large hospitals. Liquid chromatography paired with tandem mass spectrometry (LC-MS/MS) is the most widely used method and has outstanding specificity and sensitivity for fentanyl and norfentanyl. When compared to immunoassays, MS is more expensive, requires more technical skill, and takes longer to result. Newer mass spectrometry methods can measure fentanyl analogs and NSO. Both mass spectrometry assays and immunoassays [in the form of fentanyl test strips (FTS)] have potential use in harm reduction programs.

Technology-Assisted Buprenorphine Treatment in Rural and Nonrural Settings: Two Randomized Clinical Trials.

Importance: Expansion of opioid use disorder treatment is needed, particularly in rural communities. Objective: To evaluate technology-assisted buprenorphine (TAB) efficacy (1) over a longer period than previously examined, (2) with the addition of overdose education, and (3) among individuals residing in rural communities. Design, Setting, and Participants: Two parallel, 24-week randomized clinical trials were conducted at the University of Vermont between February 1, 2018, and June 30, 2022. Participants were adults with untreated opioid use disorder from nonrural (trial 1) or rural (trial 2) communities. These trials are part of a programmatic effort to develop TAB protocols to improve treatment availability in underserved areas. Interventions: Within each trial, 50 participants were randomized to TAB or control conditions. Participants in the TAB group completed bimonthly visits to ingest medication and receive take-home doses via a computerized device. They received nightly calls via an interactive voice response (IVR) system, IVR-generated random call-backs, and iPad-delivered HIV, hepatitis C virus (HCV), and overdose education. Control participants received community resource guides and assistance with contacting resources. All participants received harm reduction supplies and completed monthly assessments. Main Outcomes and Measures: The primary outcome was biochemically verified illicit opioid abstinence across monthly assessments. Secondary outcomes included self-reported opioid use in both groups and abstinence at bimonthly and random call-back visits, treatment adherence, satisfaction, and changes in HIV, HCV, and overdose knowledge among TAB participants. Results: Fifty individuals (mean [SD] age, 40.6 [13.1] years; 28 [56.0%] male) participated in trial 1, and 50 (mean [SD] age, 40.3 [10.8] years; 30 [60.0%] male) participated in trial 2. Participants in the TAB group achieved significantly greater illicit opioid abstinence vs controls at all time points in both trial 1 (85.3% [128 of 150]; 95% CI, 70.7%-93.3%; vs 24.0% [36 of 150]; 95% CI, 13.6%-38.8%) and trial 2 (88.0% [132 of 150]; 95% CI, 72.1%-95.4%; vs 21.3% [32 of 150]; 95% CI, 11.4%-36.5%). High abstinence rates were also observed at TAB participants' bimonthly dosing visits (83.0% [95% CI, 67.0%-92.0%] for trial 1 and 88.0% [95% CI, 71.0%-95.0%] for trial 2). Treatment adherence was favorable and similar between trials (with rates of approximately 99% for buprenorphine administration, 93% for daily IVR calls, and 92% for random call-backs), and 183 of 187 urine samples (97.9%) tested negative for illicit opioids at random call-backs. iPad-delivered education was associated with significant and sustained increases in HIV, HCV, and overdose knowledge. Conclusions and Relevance: In these randomized clinical trials of TAB treatment, demonstration of efficacy was extended to a longer duration than previously examined and to patients residing in rural communities. Trial Registration: ClinicalTrials.gov Identifier: NCT03420313.

Association of Urine Fentanyl Concentration With Severity of Opioid Withdrawal Among Patients Presenting to the Emergency Department.

BACKGROUND AND AIMS: Fentanyl is involved in most US drug overdose deaths and its use can complicate opioid withdrawal management. Clinical applications of quantitative urine fentanyl testing have not been demonstrated previously. The aim of this study was to determine whether urine fentanyl concentration is associated with severity of opioid withdrawal. DESIGN: This is a retrospective cross-sectional study. SETTING: This study was conducted in 3 emergency departments in an urban, academic health system from January 1, 2020, to December 31, 2021. PARTICIPANTS: This study included patients with opioid use disorder, detectable urine fentanyl or norfentanyl, and Clinical Opiate Withdrawal Scale (COWS) recorded within 6 hours of urine drug testing. MEASUREMENTS: The primary exposure was urine fentanyl concentration stratified as high (>400 ng/mL), medium (40-399 ng/mL), or low (<40 ng/mL). The primary outcome was opioid withdrawal severity measured with COWS within 6 hours before or after urine specimen collection. We used a generalized linear model with γ distribution and log-link function to estimate the adjusted association between COWS and the exposures. FINDINGS: For the 1127 patients in our sample, the mean age (SD) was 40.0 (10.7), 384 (34.1%) identified as female, 332 (29.5%) reported their race/ethnicity as non-Hispanic Black, and 658 (58.4%) reported their race/ethnicity as non-Hispanic White. For patients with high urine fentanyl concentrations, the adjusted mean COWS (95% confidence interval) was 4.4 (3.9-4.8) compared with 5.5 (5.1-6.0) among those with medium and 7.7 (6.8-8.7) among those with low fentanyl concentrations. CONCLUSIONS: Lower urine fentanyl concentration was associated with more severe opioid withdrawal, suggesting potential clinical applications for quantitative urine measurements in evolving approaches to fentanyl withdrawal management.

Urine Drug Testing Among Patients Prescribed Long-Term Opioid Therapy: Patient and Clinician Factors.

INTRODUCTION: National guidelines recommend that patients with chronic noncancer pain prescribed long-term opioid therapy (LTOT) undergo periodic urine drug testing (UDT), yet UDT is performed inconsistently, and little evidence supports the utility of this approach. We examined patient and prescriber factors associated with UDT. METHODS: A 1-year retrospective cohort study of 5690 patients prescribed LTOT by 689 clinicians in a network of 13 primary care and specialty clinics. Negative binomial regression examined patient and prescriber factors associated with the number of tests completed, and logistic regression examined prescriber and practice level testing likelihood. Analyses were adjusted for patient and clinician characteristics and accounted for patient clustering within prescribers. RESULTS: A total of 2256 patients (39.6%) had UDT completed at least once. More UDT completion was associated with Black patient race and receipt of more opioid prescriptions, as well as with clinician testing compliance. CONCLUSIONS: UDT was relatively infrequent in patients prescribed LTOT and associated with patient factors not known to confer greater opioid-related risk, such as race. In addition, there was significant clinician-driven variation in UDT. Given the uncertain clinical utility of such testing, these findings signal the need for strategies to address potential biases in the use of UDT.

Detection of 58 fentanyl analogs using ARK fentanyl II and Immunalysis fentanyl immunoassays.

OBJECTIVES: The ability to detect fentanyl analogs in urine aids in patient management. Little is published about the new ARK™ Fentanyl II Assay formulation's ability to detect fentanyl analogs. Norfentanyl (fentanyl metabolite) cross-reactivity with the ARK II assays is 7%, while the Immunalysis SEFRIA assay norfentanyl cross-reactivity is approximately 0.005%. The purpose of this study was to determine the new ARK II and SEFRIA fentanyl assays' detection of 58 fentanyl analogs. DESIGN & METHODS: Drug-free urine was fortified with 0-100 ng/mL (0-0.297 µmol/L) of the fentanyl analog and analyzed using the previously evaluated immunoassays. Results were compared to molecular structure. Of the 58 analogs tested at ≤ 100 ng/mL (0-0.297 µmol/L), the ARK II and SEFRIA assays produced 51 and 57 positive results respectively. The cross-reactivity of the assay was predominantly determined by the location of the modification. Most modifications to the aniline ring and/or amide group did not affect the ARK II or SEFRIA assay. Modifications to the piperidine ring decreased detection by ARK II assay. Of the 7 compounds which were undetected by the ARK II assay, all had modifications to the N-alkyl chain. Norsufentanil was not detected by either assay and was the only analog not detected by the SEFRIA assay. CONCLUSIONS: The ARK II and Immunalysis fentanyl immunoassays can detect a range of fentanyl analogs with acryl, butyryl, or furanyl modifications to the amide group or aniline ring of the molecule. N-alkyl chain and piperidine ring modifications significantly affect the ARK II assay's ability to detect the analogs, while the SEFRIA assay appeared less affected and detected all analogs tested except for norsufentanil, which was also not detected by the ARK II assay.

Novel Receptor-Binding-Based Assay for the Detection of Opioids in Human Urine Samples.

Consumption of opioids is a growing global health problem. The gold standard for drugs of abuse screening is immunochemical assays. However, this method comes with some disadvantages when screening for a wide variety of opioids. Detection of the binding of a compound at the human µ-opioid receptor (MOR) offers a promising alternative target. Here, we set up a urine assay to allow for detection of compounds that bind at the MOR, thus allowing the assay to be utilized as a screening tool for opioid intake. The assay is based on the incubation of MOR-containing cell membranes with the selective MOR-ligand DAMGO and urine. After filtration, the amount of DAMGO in the eluate is analyzed by liquid chromatography tandem mass spectroscopy (LC-MS/MS). The absence of DAMGO in the eluate corresponds to a competing MOR ligand in the urine sample, thus indicating opiate/opioid intake by the suspect. Sensitivity and specificity were determined by the analysis of 200 consecutive forensic routine casework urine samples. A pronounced displacement of DAMGO was observed in 29 of the 35 opiate/opioid-positive samples. Detection of fentanyl intake proved to be the most challenging aspect. Applying a cut-off value of, e.g., 10% DAMGO binding would lead to a sensitivity of 83% and a specificity of 95%. Consequently, the novel assay proved to be a promising screening tool for opiate/opioid presence in urine samples. The nontargeted approach and possible automation of the assay make it a promising alternative to conventional methods.

Urinary Pharmacokinetics of Immediate and Controlled Release Oxycodone and its Phase I and II Metabolites Using LC-MS-MS.

Oxycodone (OC) is a schedule II semisynthetic opioid in the USA that is prescribed for its analgesic effects and has a high potential for abuse. Prescriptions for OC vary based on the dosage and formulation, immediate release (IR) and controlled release (CR). Monitoring OC metabolites is beneficial for forensic casework. The limited studies that involve pharmacokinetics of the urinary excretion of OC metabolites leave a knowledge gap regarding the excretion of conjugated and minor metabolites, pharmacokinetic differences by formulation, and the impact of CYP2D6 activity on the metabolism and excretion of OC. The objectives of this study were to compare urinary excretion of phase I and II metabolites by formulation and investigate if ratio changes over time could be used to predict the time of intake. Subjects (n = 7) received a single 10 mg IR tablet of Oxycodone Actavis. A few weeks later the same subjects received a single 10 mg CR tablet of Oxycodone Actavis. During each setting, urine was collected at 0, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8, 9, 10, 12, 14, 24, 48 and 72 h. Urine samples (100 µL) were diluted with 900 µL internal standard mixture and analyzed on an Acquity UPLC® I-class coupled to a Waters Xevo TQD using a previously validated method. The CYP2D6 phenotypes were categorized as poor metabolizers (PM), intermediate metabolizers (IM), extensive metabolizers (EM) and ultrarapid metabolizers (UM). Comparisons between IR and CR were performed using two-tailed paired t-test at a significance level of P = 0.05. The metabolite ratios showed a general increase over time. Four metabolite to parent ratios were used to predict the time of intake showing that predictions were best at the early time points.

Predictors of the Rate of Illicit Fentanyl Metabolism in a Cohort of Pregnant Individuals.

INTRODUCTION: Illicit fentanyl use is growing in the United States, including among pregnant persons. Despite the prevalence of illicit fentanyl in the drug supply, the pharmacokinetics of fentanyl remains understudied, especially for pregnant individuals. The variability of fentanyl pharmacokinetics influences detection of fentanyl in urine samples, the results of which can have significant legal consequences. For pregnant and parenting individuals, these legal consequences may include termination of parental rights. METHODS: Through this medical-legal lens, we conducted a retrospective cohort analysis using the electronic medical records of women receiving integrated prenatal care and substance use disorder treatment. A total of 420 medical records were reviewed and 112 individuals who had a positive fentanyl immunoassay and met the selection criteria were included. Metabolic ratios (level of norfentanyl/level of fentanyl) were calculated for each study individual. A linear regression analysis was used to determine if the following physiologic factors were predictors of the rate of fentanyl metabolism: hepatic function, renal function, body mass index, medication dosage, gestational age, and maternal age. RESULTS: Results indicated that advanced maternal age predicted a slower conversion of fentanyl to norfentanyl, whereas increased gestational age predicted a faster conversion. CONCLUSIONS: Variations in fentanyl metabolism in pregnancy highlight the importance of clinician vigilance when interpreting fentanyl rests results, especially for individuals with advancing maternal age. In such cases, clinician caution and advocacy may prevent unwarranted and unjust removal of a child from maternal custody.

Rates and types of urine drug screen false negative results compared with confirmatory toxicology testing in major trauma patients.

BACKGROUND: Trauma centers are required to screen patients for alcohol use, and if necessary, intervene and refer to treatment (SBIRT). Similar screening for illicit drug use is recommended but not required. Urine drug screening (UDS) underestimates problematic substance use. This study aimed to estimate the types and rates of UDS false negatives (FN) compared to comprehensive testing by liquid chromatography-mass spectrometry (LC-MS) in trauma patients. METHODS: We performed a prospective cohort study of deidentified urine samples from adult trauma and burn activation patients. Both UDS and LC-MS comprehensive testing of >200 analytes were performed by a reference laboratory on all samples. Iatrogenic medications were excluded from the FN count. Crosstab analyses were conducted for UDS versus LC-MS outcomes to establish FN types and rates. We dichotomized the results by creating an "intentionality" variable (intentional injuries by self/others versus accidental injuries). A series of crosstabs with odds ratios considered intentionality by substance class and demographics. Statistically significant variables by Chi-Square were assessed by logistic regression. RESULTS: Psychoactive FN were detected in 56/100 urine samples analyzed; the most frequent included anticonvulsants (primarily gabapentin, N = 13), opioid agonists (N = 12), antihistamines (primarily diphenhydramine, N = 10), and phenethylamines (primarily bupropion, N = 5). Nonpsychoactive FN were detected in 70/100 samples; the most common were nicotine (N = 33), caffeine (N = 23), acetaminophen (N = 22), and antidepressants (N = 12). Of substance classes included in the UDS and also tested by LC-MS, FN occurred for opiates (3%), amphetamines (5%) and opioids (25%). Polypharmacy was associated with fall injuries in elderly patients. Cocaine (p = 0.015) and cannabinoids (p = 0.002) were significantly associated with intentionality. CONCLUSIONS: Our results indicate that FN for potentially important psychoactive and nonpsychoactive substances are common when toxicologic testing is limited to routine UDS in trauma patients. We recommend expanding SBIRT in this patient population to include misuse of tobacco products, prescription analgesics, and over-the-counter antihistamines.

A Cluster-Randomized Clinical Trial to Decrease Prescription Opioid Misuse: Improving the Safety of Opioid Therapy (ISOT).

BACKGROUND: Interventions to reduce harms related to prescription opioids are needed in primary care settings. OBJECTIVE: To determine whether a multicomponent intervention, Improving the safety of opioid therapy (ISOT), is efficacious in reducing prescription opioid harms. DESIGN: Clinician-level, cluster randomized clinical trial. ( ClinicalTrials.gov : NCT02791399) SETTING: Eight primary care clinics at 1 Veterans Affairs health care system. PARTICIPANTS: Thirty-five primary care clinicians and 286 patients who were prescribed long-term opioid therapy (LTOT). INTERVENTION: All clinicians participated in a 2-hour educational session on patient-centered care surrounding opioid adherence monitoring and were randomly assigned to education only or ISOT. ISOT is a multicomponent intervention that included a one-time consultation by an external clinician to the patient with monitoring and feedback to clinicians over 12 months. MAIN MEASURES: The primary outcomes were changes in risk for prescription opioid misuse (Current Opioid Misuse Measure) and urine drug test results. Secondary outcomes were quality of the clinician-patient relationship, other prescription opioid safety outcomes, changes in clinicians' opioid prescribing characteristics, and a non-inferiority analysis of changes in pain intensity and functioning. KEY RESULTS: ISOT did not decrease risk for prescription opioid misuse (difference between groups = -1.12, p = 0.097), likelihood of an aberrant urine drug test result (difference between groups = -0.04, p=0.401), or measures of the clinician-patient relationship. Participants allocated to ISOT were more likely to discontinue prescription opioids (20.0% versus 8.1%, p = 0.007). ISOT did not worsen participant-reported scores of pain intensity or function. CONCLUSIONS: ISOT did not impact risk for prescription opioid misuse but did lead to increased likelihood of prescription opioid discontinuation. More intensive interventions may be needed to impact treatment outcomes.

Impact of genetic variation in CYP2C19, CYP2D6, and CYP3A4 on oxycodone and its metabolites in a large database of clinical urine drug tests.

Urine drug testing (UDT) is a tool for monitoring drug use, including oxycodone. While variation in cytochrome P450 (CYP) genes is known to alter oxycodone metabolism, its impact on UDT results of oxycodone and its metabolites has not been well-studied. Here, multivariate analysis was performed on retrospective UDT results of 90,379 specimens collected from 14,684 genotyped patients prescribed oxycodone. Genetic variation in CYP2D6 and CYP2C19 had a significant impact on oxymorphone/oxycodone ratios, with a 6.9-fold difference between CYP2D6 ultrarapid metabolizers (UMs) and poor metabolizers (PMs; p < 10-300) and a 1.6-fold difference between CYP2C19 UMs and PMs (p = 1.50 × 10-4). CYP2D6 variation also significantly impacted noroxycodone/oxycodone ratios (p = 6.95 × 10-38). Oxycodone-positive specimens from CYP2D6 PMs were ~5-fold more likely to be oxymorphone-negative compared to normal metabolizers. These findings indicate that multivariate analysis of UDT data may be used to reveal the real-world impact of genetic and non-genetic factors on drug metabolism.

Pharmacological and metabolic characterization of the novel synthetic opioid brorphine and its detection in routine casework.

After their first emergence in 2009, Novel synthetic opioids (NSO) have become an emerging class of New Psychoactive Substances (NPS) on the market for these new drugs. So far, 67 NSO have been reported to the Early Warning system of the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA). It is presumed that NSO mainly target the four known opioid receptors, i.e. the µ-opioid (MOR), the δ-opioid (DOR), the κ-opioid (KOR) and nociceptin receptors and that their consumption can result in serious adverse effects such as massive respiratory depression or death. In the present study we investigated the in vivo and in vitro metabolism of brorphine, a NSO that was first identified on the NPS market in August 2019 in the United States, using both a pooled human liver microsome assay and real forensic case samples. For the detection of metabolites LC-HR-MS/MS was used and quantification of brorphine was performed using an LC-MS/MS method. Additionally, we pharmacologically characterized brorphine regarding its activation of the MOR and KOR via G protein recruitment using the [35S]-GTPγS assay. In forensic urine samples, 14 distinct metabolites were identified, whereas in blood only four metabolites could be found. The pooled human liver microsome assay generated six distinct in vitro phase I metabolites. The most prominent in vivo metabolite was formed by N-oxydation, whereas the main in vitro metabolite was formed by hydroxylation. The pharmacological characterization at the MOR and KOR revealed brorphine to be a potent MOR agonist and a weak, partial KOR agonist in the [35S]-GTPγS assay.

Positive Toxicology Results Are Not Associated with Emergency Physicians' Opioid Prescribing Behavior.

INTRODUCTION: Given the general lack of literature on opioid and naloxone prescribing guidelines for patients with substance use disorder, we aimed to explore how a physician's behavior and prescribing habits are altered by knowledge of the patient's concomitant use of psychotropic compounds as evident on urine and serum toxicology screens. METHODS: We conducted a retrospective chart review study at a tertiary, academic, Level I trauma center between November 2017-October 2018 that included 358 patients who were discharged from the emergency department (ED) with a diagnosis of fracture, dislocation, or amputation and received an opioid prescription upon discharge. We extracted urine and serum toxicology results, number and amount of prescription opioids upon discharge, and the presence of a naloxone script. RESULTS: The study population was divided into five subgroups that included the following: negative urine and serum toxicology screen; depressants; stimulants; mixed; and no toxicology screens. When comparing the 103 patients in which toxicology screens were obtained to the 255 patients without toxicology screens, we found no statistically significant differences in the total prescribed morphine milligram equivalent (75.0 and 75.0, respectively) or in the number of pills prescribed (15.0 and 13.5, respectively). Notably, none of the 103 patients who had toxicology screens were prescribed naloxone upon discharge. CONCLUSION: Our study found no association between positive urine toxicology results for psychotropically active substances and the rates of opioid prescribing within a single-center, academic ED. Notably, none of the 103 patients who had toxicology screens were prescribed naloxone upon discharge. More research on the associations between illicit drug use, opioids, and naloxone prescriptions is necessary to help establish guidelines for high-risk patients.

Simultaneous trace-level monitoring of seven opioid analgesic drugs in biological samples by pipette-tip micro solid phase extraction based on PVA-PAA/CNT-CNC composite nanofibers followed by HPLC-UV analysis.

Electrospun poly(vinyl alcohol)-(PVA)-poly(acrylic acid) (PAA)/carbon nanotubes(CNTs)-cellulose nanocrystal (CNC) (PVA-PAA/CNT-CNC) composite nanofibers were prepared and characterized using Fourier transform-infrared spectroscopy and field emission scanning electron microscopy. The resultant composite was used as an effective and novel sorbent for pipette-tip micro-solid phase extraction (PT-µSPE) of seven opioid analgesics (OAs) in biological samples followed by HPLC-UV analysis. Addition of CNT-CNC with the high specific surface area and plenty of OH-functional groups endows the nanofibers with considerable extraction efficiency. Under the optimum conditions, the linearity was obtained in the range 1.5 to 700.0 ng mL-1 for morphine, codeine, oxycodone, and tramadol, and 0.5 to 1000.0 ng mL-1 for nalbuphine, thebaine, and noscapine with coefficient of determination (r2) ≥ 0.9990. Detection limits (LODs) based on S/N = 3 were in the range of 0.15-0.50 ng mL-1. The relative standard deviations (RSDs) of 4.1-5.4% (intra-day, n = 5) and 5.2-6.4% (inter-day, n = 3) for three consecutive days were achieved. Finally, the efficiency of the PT-µSPE-HPLC-UV method was evaluated for the determination of OAs in human plasma and urine samples with good recoveries (87.3 to 97.8%). A: Schematic illustration for the preparation of PVA-PAA/CNT-CNC composite nanofibers. B: Schematic presentation of applying PVA-PAA/CNT-CNC composite nanofibers as the sorbent in pipette-tip micro solid-phase extraction (PT-µSPE) for the preconcentration of seven opioid analgesic drugs in biological samples before HPLC-UV analysis.

Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry and High-Sensitivity Gas Chromatography-Mass Spectrometry Screening of Classic Drugs and New Psychoactive Substances and Metabolites in Urine of Consumers.

The use of the new psychoactive substances is continuously growing and the implementation of accurate and sensible analysis in biological matrices of users is relevant and fundamental for clinical and forensic purposes. Two different analytical technologies, high-sensitivity gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) were used for a screening analysis of classic drugs and new psychoactive substances and their metabolites in urine of formed heroin addicts under methadone maintenance therapy. Sample preparation involved a liquid-liquid extraction. The UHPLC-HRMS method included Accucore™ phenyl Hexyl (100 × 2.1 mm, 2.6 µm, Thermo, USA) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2 mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2 mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode for substances identification (mass range 100-1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m, 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40-550 m/z). Urine samples from 296 patients with a history of opioid use disorder were examined. Around 80 different psychoactive substances and/or metabolites were identified, being methadone and metabolites the most prevalent ones. The possibility to screen for a huge number of psychotropic substances can be useful in suspected drug related fatalities or acute intoxication/exposure occurring in emergency departments and drug addiction services.