Sample Mining and Data Mining: Combined Real‐Time and Retrospective Approaches for the Identification of Emerging Novel Psychoactive Substances

Activity-based detection of synthetic cannabinoid receptor agonists in plant materials

BACKGROUND

Since late 2019, fortification of 'regular' cannabis plant material with synthetic cannabinoid receptor agonists (SCRAs) has become a notable phenomenon on the drug market. As many SCRAs pose a higher health risk than genuine cannabis, recognizing SCRA-adulterated cannabis is important from a harm reduction perspective. However, this is not always an easy task as adulterated cannabis may only be distinguished from genuine cannabis by dedicated, often expensive and time-consuming analytical techniques. In addition, the dynamic nature of the SCRA market renders identification of fortified samples a challenging task. Therefore, we established and applied an in vitro cannabinoid receptor 1 (CB1) activity-based procedure to screen plant material for the presence of SCRAs.

METHODS

The assay principle relies on the functional complementation of a split-nanoluciferase following recruitment of β-arrestin 2 to activated CB1. A straightforward sample preparation, encompassing methanolic extraction and dilution, was optimized for plant matrices, including cannabis, spiked with 5 µg/mg of the SCRA CP55,940.

RESULTS

The bioassay successfully detected all samples of a set (n = 24) of analytically confirmed authentic Spice products, additionally providing relevant information on the 'strength' of a preparation and whether different samples may have originated from separate batches or possibly the same production batch. Finally, the methodology was applied to assess the occurrence of SCRA adulteration in a large set (n = 252) of herbal materials collected at an international dance festival. This did not reveal any positives, i.e. there were no samples that yielded a relevant CB1 activation.

CONCLUSION

In summary, we established SCRA screening of herbal materials as a new application for the activity-based CB1 bioassay. The simplicity of the sample preparation, the rapid results and the universal character of the bioassay render it an effective and future-proof tool for evaluating herbal materials for the presence of SCRAs, which is relevant in the context of harm reduction.

Exploring trends in benzodiazepine-positive fatal drug overdoses in Tennessee, 2019-2021

BACKGROUND

Benzodiazepine-positive overdoses increased between 2019 and 2021 in Tennessee. We sought to determine the changes in the number and characteristics of prescription and illicit benzodiazepine-positive fatal drug overdoses during this period.

MATERIALS AND METHODS

A statewide study was conducted to determine changes in the number and characteristics of benzodiazepine-positive drug overdose decedents using 2019-2021 data from the Tennessee State Unintentional Drug Overdose Reporting System. The analyses were limited to Tennessee residents aged ≥ 18 years. A benzodiazepine-positive overdose was defined as any benzodiazepine on toxicology, regardless of the presence of other substances. Frequencies were generated to compare demographics, circumstances, prescription history, and toxicology between 2019 and 2021 for illicit and prescription benzodiazepine-positive fatal overdoses.

RESULTS

Between 2019 and 2021, 1666 benzodiazepine-positive unintentional or undetermined fatal drug overdoses out of 5916 total overdoses that occurred among adult Tennessee residents with available toxicological information. Prescription benzodiazepines were identified in 80.7% of deaths, whereas illicit benzodiazepines were identified in 12.0% of deaths. Many decedents had an anxiety disorder (45.5%), while over half of all decedents had a history of substance use disorder (52.3%). Most benzodiazepine-positive overdoses involved fentanyl (71.3%).

CONCLUSIONS

This analysis can inform local and regional public health workers to implement focused prevention and intervention efforts for people with co-occurring mental health conditions and substance use disorders to curb overdose epidemics among persons using benzodiazepines in Tennessee. Public health campaigns should focus on educating people on appropriate prescription medication use and the dangers of obtaining substances illicitly. Given the high proportion of opioids in this population, further education also is needed on the dangers of polysubstance drug use. The differences between prescription and illicit benzodiazepine-positive fatal overdoses indicate the need to develop substance-specific prevention and treatment strategies.

Identification of Emerging Novel Psychoactive Substances by Retrospective Analysis of Population-Scale Mass Spectrometry Data Sets

Over the last two decades, hundreds of new psychoactive substances (NPSs), also known as "designer drugs", have emerged on the illicit drug market. The toxic and potentially fatal effects of these compounds oblige laboratories around the world to screen for NPS in seized materials and biological samples, commonly using high-resolution mass spectrometry. However, unambiguous identification of a NPS by mass spectrometry requires comparison to data from analytical reference materials, acquired on the same instrument. The sheer number of NPSs that are available on the illicit market, and the pace at which new compounds are introduced, means that forensic laboratories must make difficult decisions about which reference materials to acquire. Here, we asked whether retrospective suspect screening of population-scale mass spectrometry data could provide a data-driven platform to prioritize emerging NPSs for assay development. We curated a suspect database of precursor and diagnostic fragment ion masses for 83 emerging NPSs and used this database to retrospectively screen mass spectrometry data from 12,727 urine drug screens from one Canadian province. We developed integrative computational strategies to prioritize the most reliable identifications and tracked the frequency of these identifications over a 3 year study period between August 2019 and August 2022. The resulting data were used to guide the acquisition of new reference materials, which were in turn used to validate a subset of the retrospective identifications. Last, we took advantage of matching clinical reports for all 12,727 samples to systematically benchmark the accuracy of our retrospective data analysis approach. Our work opens up new avenues to enable the rapid detection of emerging illicit drugs through large-scale reanalysis of mass spectrometry data.

Comprehensive toxicological screening of common drugs of abuse, new psychoactive substances and cannabinoids in blood using supported liquid extraction and liquid chromatography-quadrupole time-of-flight mass spectrometry

Immunoassay (IA) is currently the most widely used technique for toxicological screening in drug-impaired driving investigations. However, practical limitations in the scope of testing, and the emergence of new psychoactive substances (NPSs), have highlighted the need for alternative approaches, particularly mass spectrometry-based screening. High-resolution mass spectrometry broadens the scope of testing to include NPSs and increases analyte specificity compared to IA. In addition, it provides a platform with increased flexibility and adaptability to incorporate emerging drugs of interest due to the transient drug market. In this study, a comprehensive screening procedure was developed to identify >200 drugs of interest, including cannabinoids and NPSs in whole blood. Supported liquid extraction and liquid chromatography-quadrupole time-of-flight mass spectrometry using All Ions data acquisition were used. The method was validated in accordance with published recommendations, and all compounds of interest were identified at recommended cutoffs for driving under the influence of drug investigations. Cannabinoids, including 11-nor-9-carboxy-∆9-tetrahydrocannabinol, fentanyl analogs, buprenorphine, novel synthetic opioids and synthetic cannabinoids, were identified at low- to sub-nanogram/milliliter concentrations in whole blood using both positive and negative electrospray ionization acquisition methods.

N,N-Dimethylpentylone (dipentylone)-A new synthetic cathinone identified in a postmortem forensic toxicology case series

Synthetic cathinones emerged on the novel psychoactive substance (NPS) drug market as alternatives to controlled stimulants and entactogens such as methamphetamine and 3,4-methylenedioxymethamphetamine. The majority of synthetic cathinones can be subclassified into two groups: beta-keto amphetamines (i.e., NPS with the suffix "drone") and beta-keto methylenedioxyamphetamines (i.e., NPS with the suffix "lone"). Although a significant number of beta-keto amphetamines have been identified, beta-keto methylenedioxyamphetamines have dominated the NPS market, including notable drugs like methylone, butylone, N-ethyl pentylone (ephylone), eutylone and now N,N-dimethylpentylone. N,N-Dimethylpentylone, also known as dipentylone or beta-keto-dimethylbenzodioxolylpentanamine, emerged into the illicit drug supply <2 months of the international control of eutylone (September 2021). A novel standard addition method was developed and validated for N,N-dimethylpentylone, pentylone and eutylone, and 18 postmortem cases were quantitated using the method described in this manuscript. The resulting blood concentration range for N,N-dimethylpentylone in this case series was 3.3 to 970 ng/mL (median: 145 ng/mL, mean: 277 ± 283 ng/mL). Pentylone, a metabolite of N,N-dimethylpentylone, was detected in all cases (range: 1.3-420 ng/mL, median: 31 ng/mL and mean: 88 ± 127 ng/mL). Due to the rise in identifications of N,N-dimethylpentylone in postmortem investigations as well as the potential misidentification of N,N-dimethylpentylone as N-ethyl pentylone, samples testing positive for pentylone should be additionally confirmed for the presence of N,N-dimethylpentylone. Based on prior trends of new synthetic cathinones, it can be theorized that N,N-dimethylpentylone may predominate the US synthetic stimulant market for the next 1-2 years; however, given the emergence of additional closely related isomeric compounds, it is important to utilize methodology capable of differentiating N,N-dimethylpentylone from its isomers (N-isopropylbutylone, N-ethyl pentylone, N-ethyl N-methyl butylone, hexylone, N-propylbutylone, diethylone and tertylone).

Method development, validation, and application for simultaneous determination of 56 new psychoactive substances in surface water by LC-MS/MS

Despite preventive legislation, the popularity and consumption of new psychoactive substances (NPS) have been steadily increasing in recent years. This study provides a rapid and sensitive method for the quantitation and the detection of 56 NPS from surface water. Sample clean-up and pre-concentration were performed by solid-phase extraction (SPE) with Oasis HLB (6 cc/500 mg) cartridge. Following the chromatographic separation with Shim-pack FC-ODS column, the all substances were quantified by liquid chromatography-tandem mass spectrometry. The method was optimized and validated for all NPS. Despite the wide variety of physicochemical properties of the analytes, the recoveries for all compounds studied were in the range of 69-117%. The limit of quantitation (LOQ) ranging from 2.5 to 15 ng/L was reached for reliable and accurate quantification of analytes. The analytical method developed was successfully applied to the surface water samples. While synthetic cannabinoids were not detected, mephedrone from the synthetic cathinone group was detected under the LOQ. This novel method was expected to be a part of future environmental routine analyses as a satisfactory method.

A Collaborative Platform for Novel Compound Identification - Characterization of Designer Phencyclidines (PCPs) POXP, PTHP, and P2AP

With the sustained prevalence and introduction of new emerging drugs throughout the world there is a need for continued development and maintenance of platforms that enable rapid identification and characterization of unknown compounds. To complement existing efforts, a collaborative platform between the National Institute of Standards and Technology (NIST) and practicing forensic agencies is being deployed which enables laboratories to leverage techniques and expertise that may not exist at their facilities. Using this approach, unknown compounds are identified and characterized using a suite of analytical tools to obtain (1) a rapid preliminary identification followed by (2) a more complete characterization and confirmation of the preliminary identification. To demonstrate this platform, the characterization of three previously unreported analogs of phencyclidine (PCP) - POXP, PTHP, and P2AP - are described. A preliminary identification of the three substances was obtained using direct analysis in real time mass spectrometry (DART-MS) with confirmation by nuclear magnetic resonance (NMR) spectroscopy, gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detection (GC-FID).

Opioid overdoses involving xylazine in emergency department patients: a multicenter study

INTRODUCTION

Illicit opioids, consisting largely of fentanyl, novel synthetic opioids, and adulterants, are the primary cause of drug overdose fatality in the United States. Xylazine, an alpha-2 adrenergic agonist and veterinary tranquilizer, is being increasingly detected among decedents following illicit opioid overdose. Clinical outcomes in non-fatal overdose involving xylazine are unexplored. Therefore, among emergency department patients with illicit opioid overdose, we evaluated clinical outcome differences for patients with and without xylazine exposures.

METHODS

This multicenter, prospective cohort study enrolled adult patients with opioid overdose who presented to one of nine United States emergency departments between 21 September 2020, and 17 August 2021. Patients with opioid overdose were screened and included if they tested positive for an illicit opioid (heroin, fentanyl, fentanyl analog, or novel synthetic opioid) or xylazine. Patient serum was analyzed via liquid chromatography quadrupole time-of-flight mass spectroscopy to detect current illicit opioids, novel synthetic opioids, xylazine and adulterants. Overdose severity surrogate outcomes were: (a) cardiac arrest requiring cardiopulmonary resuscitation (primary); and (b) coma within 4 h of arrival (secondary).

RESULTS

Three hundred and twenty-one patients met inclusion criteria: 90 tested positive for xylazine and 231 were negative. The primary outcome occurred in 37 patients, and the secondary outcome occurred in 111 patients. Using multivariable regression analysis, patients positive for xylazine had significantly lower adjusted odds of cardiac arrest (adjusted OR 0.30, 95% CI 0.10-0.92) and coma (adjusted OR 0.52, 95% CI 0.29-0.94).

CONCLUSIONS

In this large multicenter cohort, cardiac arrest and coma in emergency department patients with illicit opioid overdose were significantly less severe in those testing positive for xylazine.

Acute Intoxications and Fatalities Associated With Benzimidazole Opioid (Nitazene Analog) Use: A Systematic Review

BACKGROUND

Synthetic benzimidazole opioids (BOs) are highly potent µ-opioid receptor agonists with heroin-like effects. Isotonitazene was first available in 2019 in the drug market, although new analogs have multiplied recently. The authors aimed to identify BO use trends and gather toxicological data from BO-related cases to assist in clinical and forensic investigations.

METHODS

A systematic literature search was conducted according to the PRISMA guidelines. PubMed and Scopus databases were accessed in October 2021 to identify scientific reports of BO-related intoxication and fatalities. Publication dates, case descriptions, symptoms, autopsy findings, and concentrations of BOs and metabolites in biological matrices were compiled.

RESULTS

Data from 8 case reports with 93 fatalities involving isotonitazene ( n = 65), metonitazene ( n = 20), etonitazepyne ( N -pyrrolidino etonitazene) ( n = 8), flunitazene ( n = 4), and/or butonitazene ( n = 1), and 1 acute intoxication involving etonitazepyne were collected. Autopsy findings included pulmonary congestion/high lung weight (66%), cardiomegaly/high cardiac weight (39%), cerebral edema (22%), gastric contents in the airways (22%), and organ congestion (22%). Median peripheral blood concentrations were 1.7 ng/mL for isotonitazene (0.4-9.5 ng/mL, n = 13), 5.4 ng/mL for metonitazene (0.52-33 ng/mL, n = 17), 5.4 ng/mL for etonitazepyne (2.4-8.3 ng/mL, n = 2), 1.3 ng/mL for flunitazene (0.58-2.1 ng/mL, n = 2), and 3.2 ng/mL for butonitazene ( n = 1). Central nervous system depressants were almost always coadministered.

CONCLUSIONS

Isotonitazene was predominant in cases from 2019 to mid-2020 and was replaced by metonitazene after scheduling in the United States. Typical findings on opioid overdoses have been reported. Peripheral blood concentrations were consistent with a potency similar to that of fentanyl. These results must be interpreted carefully, considering the scarcity of reports on BO-related cases and drug co-exposures.

Liquid Chromatography High Resolution Mass Spectrometry in Forensic Toxicology: What Are the Specifics of Method Development, Validation and Quality Assurance for Comprehensive Screening Approaches?

The use of High Resolution Mass Spectrometry (HRMS) has increased over the past decade in clinical and forensic toxicology, especially for comprehensive screening approaches. Despite this, few guidelines of this field have specifically addressed HRMS issues concerning compound identification, validation, measurement uncertainty and quality assurance. To fully implement this technique, certainly in an era in which the quality demands for laboratories are ever increasing due to various norms (e.g. the International Organization for Standardization's ISO 17025), these specific issues need to be addressed. This manuscript reviews 26 HRMS-based methods for qualitative systematic toxicological analysis (STA) published between 2011 and 2021. Key analytical data such as samples matrices, analytical platforms, numbers of analytes and employed mass spectral reference databases/libraries as well as the studied validation parameters are summarized and discussed. The article further includes a critical review of targeted and untargeted data acquisition approaches, available HRMS reference databases and libraries as well as current guidelines for HRMS data interpretation with a particular focus on identification criteria. Moreover, it provides an overview on current recommendations for the validation and determination measurement uncertainty of qualitative methods. Finally, the article aims to put forward suggestions for method development, compound identification, validation experiments to be performed, and adequate determination of measurement uncertainty for this type of wide-range qualitative HRMS-based methods.

Toxicological and pharmacological characterization of novel cinnamylpiperazine synthetic opioids in humans and in vitro including 2-methyl AP-237 and AP-238

The recent scheduling actions of fentanyl-related substances in both the United States and China have sparked the emergence and proliferation of other generations of "legal" opioids that are structurally distinct from fentanyl, including the recently emerged class of cinnamylpiperazines. In contrast to fentanyl, which contains a piperidine core and a phenethyl moiety, the primary structural components of cinnamylpiperazines are the piperazine core and a cinnamyl moiety. This manuscript reports on the toxicological profile for antemortem and postmortem cases where a cinnamylpiperazine was detected. Samples were quantitatively confirmed using liquid chromatography tandem mass spectrometry. The cases were received between February 2020 and April 2021. Concentrations of 2-methyl AP-237 from four postmortem cases ranged from 820 to 5800 ng/mL, and concentrations of AP-238 from two postmortem cases were 87 and 120 ng/mL. µ-Opioid receptor (MOR) activation potential for 2-methyl AP-237, AP-237, para-methyl AP-237, and AP-238 were studied using a βarr2 recruitment assay. Efficacies (E_max, relative to hydromorphone) and potencies (EC₅₀) were derived and of the compounds tested AP-238 was the most potent compound in the panel with an EC₅₀ of 248 nM. 2-Methyl AP-237 was found to be the most efficacious drug (E_max = 125%) of the tested cinnamylpiperazines; however, it had substantially less efficacy than fentanyl. The in vitro MOR activation potential of the studied cinnamylpiperazines was lower than that of fentanyl and other novel synthetic opioids (NSOs), in line with the relatively higher concentrations observed in postmortem toxicology samples-an important observational link between in vitro pharmacology and in vivo toxicology.

Metonitazene in the United States-Forensic toxicology assessment of a potent new synthetic opioid using liquid chromatography mass spectrometry

Metonitazene is considered a new psychoactive substance (NPS) and emerging potent synthetic opioid, causing increased public health concern beginning in 2020. Metonitazene joins a growing list of new synthetic opioids (NSOs) contributing to deaths among people who use drugs in the United States and other parts of the world. Metonitazene (a 2-benzylbenzimidazole analogue) first appeared in mid-2020 in the recreational drug supply and subsequently began proliferating in death investigation casework towards the end of 2020. Screening and metabolite discovery were performed by liquid chromatography quadrupole time-of-flight mass spectrometry. Quantitative confirmation was performed by liquid chromatography tandem quadrupole mass spectrometry. Metonitazene was confirmed in 20 authentic forensic postmortem cases with an average concentration in blood at 6.3 ± 7.5 ng/ml (median: 3.8 ng/ml, range: 0.5-33 ng/ml, n = 18) and in urine at 15 ± 13 ng/ml (median: 11 ng/ml, range: 0.6-46 ng/ml, n = 14). Metonitazene was the only opioid identified in 30% of cases but was also found in combination with fentanyl (55%) and NPS benzodiazepines, opioids, and hallucinogens (45%). Medical examiners included metonitazene as a drug responsible for the cause of death, and the manner of death was always ruled to be an accident. The metabolism of metonitazene was found to be similar to that of isotonitazene, a closely related analogue. Toxicology laboratories and death investigators should ensure that metonitazene is included in forensic testing protocols, all while remaining vigilant for subsequent NSOs to emerge.

Sentanyl: a comparison of blood fentanyl concentrations and naloxone dosing after non-fatal overdose

INTRODUCTION

Non-pharmaceutical fentanyl and its analogs have driven striking increases in opioid-associated overdose deaths. These highly potent opioids can be found at low concentrations in biological specimens. Little is known regarding the concentrations of these substances among survivors of non-fatal overdoses. In a locale where fentanyl is responsible for the majority of non-fatal opioid overdoses, we compared the concentration of fentanyl in blood to naloxone dosing in the presence and absence of a concurrent sedative-hypnotic exposure.

METHODS

In this pilot study, we enrolled adult patients presenting to the emergency department (ED) who: (1) arrived after an overdose requiring naloxone for the reversal of respiratory depression; and (2) who required venipuncture or intravenous access as part of their clinical care. Blood specimens (n = 20) underwent comprehensive toxicology testing, including the quantitation of fentanyl, fentanyl analogs, and naloxone, as well as the detection of common sedative-hypnotics and a wide range of other illicit and pharmaceutical substances. We then compared fentanyl concentrations to naloxone dosing in participants with and without a concomitant sedative-hypnotic exposure.

RESULTS

Nineteen of twenty participants (95%) were exposed to fentanyl prior to their overdose; the remaining participant tested positive for heroin metabolites. No participants reported pharmaceutical fentanyl use. Fentanyl analogs - acetylfentanyl or carfentanil - were present in three specimens. In 11 cases, fentanyl and its metabolites were the only opioids identified. Among the fentanyl-exposed, blood concentrations ranged from <0.1-19 ng/mL with a mean of 6.2 ng/mL and a median of 3.6 ng/mL. There was no relationship between fentanyl concentration and naloxone dose administered for reversal. We detected sedative-hypnotics (including benzodiazepines, muscle relaxants, and antidepressants) in nine participants. Among the sedative-hypnotic exposed, fentanyl concentrations were lower, but naloxone dosing was similar to those without a concomitant exposure.

CONCLUSIONS

In this study, we found that: 1) fentanyl was present in the blood of nearly all participants; 2) fentanyl concentrations were lower among study participants with concomitant sedative-hypnotic exposure; and 3) the dose of naloxone administered for overdose reversal was not associated with the measured fentanyl concentration in blood specimens. Our results underscore the role that tolerance and concomitant drug exposure play in the precipitation and resuscitation of management of opioid overdose.

The Rise and Fall of Isotonitazene and Brorphine: Two Recent Stars in the Synthetic Opioid Firmament

Synthetic opioids constitute one of the fastest growing groups of new psychoactive substances (NPS) worldwide. With fentanyl analogues being increasingly controlled via class-wide scheduling, many non-fentanyl related opioids are now emerging on the recreational opioid market, rendering the landscape highly complex and dynamic. While new compounds are entering the supply in rapid and unpredictable manners, some recent patterns have become apparent. Many of these newly emerging opioids are being pirated from early patent literature and/or research papers, synthesized and sold online through various channels. Burdened by the identification of every newly emerging drug, many toxicology labs struggle to keep up. Moreover, by the time a "new" drug is controlled via legislative measures, illicit drug markets will have already adapted and diversified as manufacturers work to avoid the restricted product(s). Hence, the typical life-cycle of an NPS opioid is generally short (less than 6 months to one year), with only a few drugs escalating to significant numbers of detections. In this review, we summarize the key events in the emergence, rise, and subsequent decline of two non-fentanyl opioids - isotonitazene and brorphine. These two opioids sequentially dominated the NPS opioid market in 2019 and 2020. Both isotonitazene and brorphine remained in circulation for over a year, each contributing to hundreds of deaths and adverse events. By detailing the life-cycles of these opioids from their earliest synthesis as described in scientific literature to their subsequent rise and fall on recreational markets, this review illustrates the new characteristic life-cycle of synthetic opioids in the 'post-fentanyl-analogue' era.

Eutylone and Its Structural Isomers Interact with Monoamine Transporters and Induce Locomotor Stimulation

Synthetic cathinones are a class of new psychoactive substances that induce psychostimulant effects and pose risk for hospitalizations, overdose, and death. At the present time, derivatives of the synthetic cathinone, methylone, are being confiscated in nonmedical (i.e., recreational) drug markets worldwide. In particular, eutylone is a newly emerging methylone analog that possesses ethyl groups at the α-carbon and amine positions. Little information is available about the pharmacological effects of eutylone, but based on its structure, we surmised that the compound interacts with monoamine transporters in the brain. To test this hypothesis, we compared the effects of eutylone and its structural isomers, dibutylone and pentylone, using in vitro transporter assays in rat brain synaptosomes and in vivo locomotor activity assessments in mice. All drugs displayed dose-related inhibition of [³H]neurotransmitter uptake at dopamine transporters (DAT) and norepinephrine transporters (NET), but effects at DAT were 10-fold more potent (IC₅₀ = 120 nM). Eutylone and pentylone inhibited uptake at serotonin transporters (SERT), while dibutylone did not. Additionally, eutylone and pentylone displayed weak partial releasing actions at SERT which achieved 50% of maximal response. All drugs stimulated dose-related locomotion in mice, and eutylone was most potent and efficacious in this regard (ED₅₀ = 2 mg/kg, sc). Our results demonstrate that eutylone is a hybrid transporter compound with uptake inhibition properties at DAT and NET but substrate activity at SERT. The effects of eutylone are similar to those produced by pentylone, which suggests that eutylone will exhibit abuse liability and pose risks for psychostimulant side-effects in human users.

Phenethyl-4-ANPP: a Marginally Active Byproduct Suggesting a Switch in Illicit Fentanyl Synthesis Routes

Profiling of the illicit fentanyl supply is invaluable from surveillance and intelligence perspectives. An important strategy includes the study of chemical attribution signatures (e.g. trace amounts of synthesis precursors, impurities/byproducts in seized material, metabolites in biological samples). This information provides valuable insight into the employed synthesis routes at the heart of illicit fentanyl manufacture (previously mainly the so-called Janssen or Siegfried methods), allowing to track and ultimately regulate crucial precursors. This report focuses on phenethyl-4-ANPP, a formerly unknown compound that was identified for the first time in a fentanyl powder sample seized in April 2019, followed by its identification in a biological sample in December 2019. Between 2019-Q4 and 2020-Q3, phenethyl-4-ANPP was detected in 25/1054 fentanyl cases in the United States. There are currently no reports on how this compound may have ended up in illicit drug preparations and whether its presence may have potential in vivo relevance. We propose three possible fentanyl synthesis routes which, when badly executed in a single reaction vessel, may involve the formation of phenethyl-4-ANPP. We hypothesize that the presence of the latter is the result of a shift in fentanyl synthesis routes in an attempt to circumvent restrictions on previously used precursors. Using a cell-based µ-opioid receptor (MOR) recruitment assay, we show that the extent of MOR activation caused by 100 µM phenethyl-4-ANPP is comparable to that exerted by a roughly 100,000-fold lower concentration of fentanyl (0.001 µM or 0.336 ng/mL). Negligible in vitro opioid activity, combined with its low abundance in fentanyl preparations, most likely renders phenethyl-4-ANPP biologically irrelevant in vivo. However, as clandestine operations are constantly changing shape, monitoring of fentanyl attributions remains pivotal in our understanding and control of illicit fentanyl manufacture and supply.

International snapshot of new psychoactive substance use: Case study of eight countries over the 2019/2020 new year period

There is considerable concern around the use of new psychoactive substances (NPS), but still little is known about how much they are really consumed. Analysis by forensics laboratories of seized drugs and post-mortem samples as well as hospital emergency rooms are the first line of identifying both 'new' NPS and those that are most dangerous to the community. However, NPS are not necessarily all seized by law enforcement agencies and only substances that contribute to fatalities or serious afflictions are recorded in post-mortem and emergency room samples. To gain a better insight into which NPS are most prevalent within a community, complementary data sources are required. In this work, influent wastewater was analysed from 14 sites in eight countries for a variety of NPS. All samples were collected over the 2019/2020 New Year period, a time which is characterized by celebrations and parties and therefore a time when more NPS may be consumed. Samples were extracted in the country of origin following a validated protocol and shipped to Australia for final analysis using two different mass spectrometric strategies. In total, more than 200 were monitored of which 16 substances were found, with geographical differences seen. This case study is the most comprehensive wastewater analysis study ever carried out for the identification of NPS and provides a starting point for future, ongoing monitoring of these substances.

Concentrations of para-Fluorofuranylfentanyl (FFF) in Paired Central and Peripheral Blood Collected During Postmortem Death Investigations

The opioid epidemic in the United States (U.S.) has been associated with an increasing mortality rate in large part due to the emergence and proliferation of synthetic opioids over the last fifteen years. Fentanyl and its analogues have played a large part in these statistics due to their potency and toxicity. Fluorofuranylfentanyl (FFF) is a fentanyl analogue that emerged in the U.S. in 2018 and was associated with numerous adverse events and deaths. During this study, a liquid chromatography tandem mass spectrometry (LC-MS/MS) workflow was developed to accurately identify the isomer of FFF present (ortho- vs. meta- vs. para-) in medicolegal death investigation cases from Pinellas County, Florida. FFF was quantified in central and peripheral blood samples collected at autopsy. In addition, the metabolism of FFF was studied using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). para-FFF was quantitatively confirmed in 29 postmortem cases; no other isomer of FFF was detected. Central blood concentrations ranged between 0.66 and 73 ng/mL (mean = 11±14 ng/mL, median = 10 ng/mL) and peripheral blood concentrations ranged between 0.53 and 23 ng/mL (mean = 5.7±6.4 ng/mL, median = 2.7 ng/mL). Comparison of central to peripheral blood concentrations were evaluated to determine the possibility of postmortem redistribution (PMR). The metabolism of ortho-FFF was studied and found to undergo metabolic processes similar to fentanyl, producing ortho-fluorofuranyl-norfentanyl, fluoro-4-ANPP, and hydroxylated species. The results of this study demonstrate the toxicity of FFF and its implication in medicolegal death investigations. Laboratories must remain aware of new or re-emerging fentanyl analogues, as they pose significant risks to public health and public safety.

Eutylone Intoxications-An Emerging Synthetic Stimulant in Forensic Investigations

Synthetic stimulants are the largest class of novel psychoactive substances identified each year by forensic laboratories internationally. While hundreds of these drugs appear in drug powders, only a few proliferate in use among forensically relevant populations and eventually emerge in postmortem and clinical investigations. Beta-keto-methylenedioxyamphetamines (i.e., novel psychoactive substances with names ending in "ylone") are currently the most popular subclass of synthetic stimulants. Leading up to its federal scheduling in 2018, N-ethyl pentylone was the most encountered synthetic stimulant. The popularity of N-ethyl pentylone declined once it was scheduled, but it was quickly replaced by eutylone (bk-EBDB), a structurally related analog from the same family. In cases encountered between January 2019 and April 2020, eutylone was quantitatively confirmed in 83 forensic investigations, including postmortem cases and driving under the influence of drugs cases. Matrix types included blood, urine and tissue. Eutylone was identified in cases submitted from 13 states, demonstrating proliferation around the United States; Florida accounted for 60% of the positive cases. The mean concentration of eutylone in postmortem blood was 1,020 ng/mL (standard deviation = ±2,242 ng/mL; median = 110 ng/mL, range = 1.2-11,000 ng/mL, n = 67). The mean concentration of eutylone in blood from driving under the influence of drugs cases was 942 ng/mL (standard deviation = ±1,407 ng/mL; median = 140 ng/mL, range = 17-3,600 ng/mL, n = 7). This report includes cause and manner of death data for 22 postmortem cases. Further analysis of authentic human specimens revealed the presence of three eutylone metabolites, including one unique biomarker and one metabolite in common with butylone. Laboratories should be aware that eutylone may be present in cases of suspected Ecstasy, "Molly" and/or methylenedioxymethamphetamine use, causing or contributing to impairment or death.

Comprehensive UHPLC-HR-MSE screening workflow optimized for use in routine laboratory medicine: Four workflows in one analytical method

A comprehensive HR-MS screening can be used to identify thousands of drugs from a single analysis, which makes it a valuable tool for broad-scope component-resolved toxicological analysis. However, it is common practice in clinical toxicology to perform restricted data analysis to avoid examining and/or reporting data not requested for examination. In this study, a HR-MS screening workflow was developed to allow a comprehensive toxicological evaluation, but also restricted and levelled data analysis to fit in a clinical setting. Following precipitation and reconstitution, samples were injected on an UHPLC-HR-MS and data were analyzed with the data processing software UNIFI. Analytical validation of 38 selected drugs of abuse (DoA), included determination of matrix effect, recovery, process efficiency, and limit of identification (LOI). The method was tested on 49 authentic samples and matrix-matched ranges of calibrators for 95 drugs. The LOI ranged from 0.3 to 1426.7 ng mL^-1 for most analytes which was within expected concentration range for authentic samples with THC-COOH (>1722.0 ng mL^-1) and morphine (1426.7 ng mL^-1) as notable exceptions. Four individual screening workflows were developed: 1) a targeted workflow to serve as orthogonal identification of the 38 selected DOAs from another in-house method, 2) a general toxicology workflow, 3) an extended toxicology workflow including new psychoactive substances (NPS), and 4) a workflow for NPS based on the online HighResNPS library. Our study presents a comprehensive LC-HR-MS toxicology screening method optimized for laboratory medicine. The workflow allows for levelled data reviewing when requested without compromising the ability to perform full toxicological analyses.

Toward a National System of Expanded Testing of Existing Urine Specimens: The Drug Outbreak Testing Service (DOTS)

BACKGROUND

NIDA's National Drug Early Warning System (NDEWS) was established in 2014 with the mission of identifying and monitoring emerging drugs in the United States. Identification of emerging drugs has been complicated, however, by the rapid development of novel psychoactive substances such that users often cannot identify and report the drugs they have ingested. Biologic testing of urine, hair or blood is the only way to reliably identify the substances recently used. Unfortunately, the large number of up-to-date tests required is beyond the resources available to most organizations.

METHODS

The DOTS study tested the feasibility of recruiting organizations to submit up to 25 de-identified urine specimens for testing for approximately 240 drugs, at no cost to them. The results were for epidemiologic purposes only and not for clinical use. Eleven sites who had questions about their patients or the results of their organization's more limited urinalysis screens participated. These sites included drug treatment programs, medical examiners, hospitals and a criminal justice testing program.

RESULTS

Extensive polydrug use and geographic differences in the drugs detected were found. All sites found the DOTS collaborating laboratory's test results to be very useful for understanding the types of drugs being used recently and to assess the adequacy of their testing protocols.

CONCLUSIONS

The U.S. should consider establishing a program of expanded testing of already collected de-identified urine specimens in order to identify emerging drugs and track local patterns of use and availability.

U-47700 and Its Analogs: Non-Fentanyl Synthetic Opioids Impacting the Recreational Drug Market

The recreational use of opioid drugs is a global threat to public health and safety. In particular, an epidemic of opioid overdose fatalities is being driven by illicitly manufactured fentanyl, while novel synthetic opioids (NSOs) are appearing on recreational drug markets as standalone products, adulterants in heroin, or ingredients in counterfeit drug preparations. Trans-3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide (U-47700) is a prime example of a non-fentanyl NSO that is associated with numerous intoxications and fatalities. Here, we review the medicinal chemistry, preclinical pharmacology, clandestine availability, methods for detection, and forensic toxicology of U-47700 and its analogs. An up-to-date summary of the human cases involving U-47700 intoxication and death are described. The evidence demonstrates that U-47700 is a potent μ-opioid receptor agonist, which poses a serious risk for overdosing and death. However, most analogs of U-47700 appear to be less potent and have been detected infrequently in forensic specimens. U-47700 represents a classic example of how chemical entities from the medicinal chemistry or patent literature can be diverted for use in recreational drug markets. Lessons learned from the experiences with U-47700 can inform scientists, clinicians, and policymakers who are involved with responding to the spread and impact of NSOs.

The next generation of synthetic cannabinoids: Detection, activity, and potential toxicity of pent-4en and but-3en analogues including MDMB-4en-PINACA

A new class of synthetic cannabinoids has emerged as new psychoactive substances (NPS). Similar in structure to JWH-022, these substances contain alkene modifications to the tail region of the synthetic cannabinoid core structure, and nomenclature denotes these new analogues as pent-4en or but-3en species. Internationally, two analogues from this new series recently emerged: MDMB-4en-PINACA and MMB-4en-PICA. Previously, data regarding activity and potential toxicity were not available. In vitro assessment of cannabinoid receptor 1 (CB1) activation via the β-arrestin 2 recruitment was studied for three (3) pent-4en analogues, one (1) but-3en analogue, and one (1) principal metabolite. MDMB-4en-PINACA (2.47 nM, 239%), MDMB-4en-PICA (11.5 nM, 302%), and MDMB-3en-BINACA (14.3 nM, 286%) were highly potent and efficacious (comparison: JWH-018, 25.3 nM, 100%), while the potencies of MMB-4en-PICA and MDMB-4en-PINACA 3,3-dimethylbutanoic acid were markedly lower. Modifications to core and tail structural features (i.e., indole vs. indazole) led to relatively small differences in potency, while changes among the head region led to larger differences. Sample-mining and data-mining conducted on toxicology samples led to the identification of MDMB-4en-PINACA in 25 forensic toxicology cases, including postmortem and impaired driving investigations, with case details and limited histories described herein. Moderate geographical distribution of MDMB-4en-PINACA was noted in the United States with emergence in the Northeast, Midwest, South, and West regions. Results from toxicology testing paired with case history show the potential for MDMB-4en-PINACA to cause or contribute to impairment or death. Forensic scientists, public health and public safety officials, law enforcement, clinicians, medical examiners, and coroners should consider involvement of emergent synthetic cannabinoids in their work and that new analogues containing an alkene tail can retain similar or increased potency and toxicity.

Determining changes in new psychoactive substance use in Australia by wastewater analysis

Measuring community consumption of new psychoactive substances (NPS) is notoriously difficult to assess by traditional means such as surveys and seizure data. Previously, we used the approach to demonstrate the prevalence of NPS on a national scale. In the current study we explored the temporal resolution for the analysis of NPS in wastewater from Australia. Samples covering all States and Territories in Australia and both metropolitan and regional areas and were collected bimonthly from October 2017-June 2018 and October 2019-February 2020. A qualitative screening method was applied, screening for 201 NPS. In total, 15 substances were found from a variety of classes of NPS. The most prevalent class was synthetic cathinones, with pentylone, N-ethylpentylone and ethylone found in all periods in at least one site in the earlier sampling period, as well as the amphetamine-like paramethoxyamphetamine (PMA). In the latter period, synthetic cathinones were also the most prevalent, including eutylone, marking the first time that this compound has been detected in wastewater. This study shows the application of wastewater analysis to detect outbreaks of NPS use and temporal differences among sites.

Isotonitazene Quantitation and Metabolite Discovery in Authentic Forensic Casework

The synthetic opioid landscape continues to change as non-fentanyl-related substances appear in forensic toxicology casework. Among the newest synthetic opioids to emerge is isotonitazene, an analogue of a benzimidazole class of analgesic compounds. Isotonitazene is an active and potent synthetic opioid, but the extent to which this compound is causing toxicity among drug users was previously unknown. This report describes the confirmation and quantitation of isotonitazene in blood, urine and vitreous fluid through standard addition, as well as in vivo metabolic profile determination in drug users. Quantitative analysis was performed using liquid chromatography tandem mass spectrometry (LC–MS/MS), and metabolite discovery was performed using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). In total, 18 cases were confirmed positive for isotonitazene, nine of which were previously negative for any opioid. The average isotonitazene concentration in blood was 2.2 ± 2.1 ng/mL (median 1.75 ng/mL, range 0.4–9.5 ng/mL), and the average isotonitazene concentration in urine was 2.4 ± 1.4 ng/mL (median 2.7 ng/mL, range 0.6–4.0 ng/mL). The lowest concentration of isotonitazene in blood was 0.4 ng/mL (two cases) with no other opioids present; findings in death investigations. Four metabolites of isotonitazene were detected in vivo. N- and O-dealkylation products were determined to be the most prominent urinary biomarkers, while 5-amino-isotonitazene was identified in most blood samples. The prevalence and popularity of isotonitazene continue to increase in the United States in early 2020. Toxicologists, medical examiners and coroners should be aware of novel opioids outside the standard scope of testing, especially in medicolegal death investigations. Forensic scientists should add isotonitazene to testing procedures, and public health officials should counsel about potent new drugs and the dangers of opioid use.