An outbreak of synthetic cannabinoid exposures reported to a regional poison center: "K2" identified as 5F-ADB

Structure-Activity Relationships, Deuteration, and Fluorination of Synthetic Cannabinoid Receptor Agonists Related to AKB48, 5F-AKB-48, and AFUBIATA

Synthetic cannabinoid receptor agonists (SCRAs) are a growing class of new psychoactive substances (NPS) commonly derived from an N-alkylated indole, indazole, or 7-azaindole scaffold. Diversification of this core (at the 3-position) with amide-linked pendant amino acid groups and modular N-alkylation (of the indole/indazole/7-azaindole core) ensures that novel SCRAs continue to enter the illicit drug market rapidly. In response to the large number of SCRAs that have been detected, pharmacological evaluation of this NPS class has become increasingly common. Adamantane-derived SCRAs have consistently appeared throughout the market since 2011, and as such, a systematic set of these derivatives was synthesized and pharmacologically evaluated. Deuterated and fluorinated adamantane derivatives were prepared to evaluate typical hydrogen bioisosteres, as well as evaluation of the newly detected AFUBIATA.

Investigating selectivity and bias for G protein subtypes and β-arrestins by synthetic cannabinoid receptor agonists at the cannabinoid CB1 receptor

The cannabinoid CB1 receptor (CB1) is a G protein-coupled receptor (GPCR) with widespread expression in the central nervous system. This canonically G⍺i/o-coupled receptor mediates the effects of Δ9-tetrahydrocannabinol (THC) and synthetic cannabinoid receptor agonists (SCRAs). Recreational use of SCRAs is associated with serious adverse health effects, making pharmacological research into these compounds a priority. Several studies have hypothesised that signalling bias may explain the different toxicological profiles between SCRAs and THC. Previous studies have focused on bias between G protein activation measured by cyclic adenosine monophosphate (cAMP) inhibition and β-arrestin translocation. In contrast, the current study characterises bias between G⍺ subtypes of the G⍺i/o family and β-arrestins; this method facilitates a more accurate assessment of ligand bias by assessing signals that have not undergone major amplification. We have characterised G protein dissociation and translocation of β-arrestin 1 and 2 using real-time BRET reporters. The responses produced by each SCRA across the G protein subtypes tested were consistent with the responses produced by the reference ligand AMB-FUBINACA. Ligand bias was probed by applying the operational analysis to determine biases within the G⍺i/o family, and between G protein subtypes and β-arrestins. Overall, these results confirm SCRAs to be balanced, high-efficacy ligands compared to the low efficacy ligand THC, with only one SCRA, 4CN-MPP-BUT7IACA, demonstrating statistically significant bias in one pathway comparison (towards β-arrestin 1 when compared with G⍺oA/oB). This suggests that the adverse effects caused by SCRAs are due to high potency and efficacy at CB1, rather than biased agonism.

Involuntary MDMB-4en-PINACA intoxications following cannabis consumption: clinical and analytical findings

BACKGROUND AND AIMS

MDMB-4en-PINACA is a synthetic cannabinoid receptor agonist (SCRA) that has recently emerged. Data regarding clinical presentations in the event of intoxication is scarce. This study presents MDMB-4en-PINACA identification in cannabis consumers with clinical and analytical descriptions.

METHODS

Between November 2020 and March 2021, all patients with unexpected or unusually severe effects and Poisoning Severity Score (PSS) greater than or equal to 2 after cannabis consumption were included. Blood and/or urine samples were collected for toxicological analysis. When available, drug material samples were also collected for analysis.

RESULTS

Between November 2020 and March 2021, 13 patients were included. All cases typically presented with altered mental status (n = 13), and nearly all had returned to a normal or quasi-normal state after around 11 h of observation. Neurological symptoms included headaches (n = 3), hallucinations (3), mydriasis (3), amnesia (2) and seizures (5). Psychiatric symptoms were paranoia (6) and anxiety (2). Digestive symptoms were nausea (2) and vomiting (6). No deaths were recorded. All patients were positive for the SCRA MDMB-4en-PINACA in urine, blood and/or drug material sample. Results from toxicology testing paired with case history showed the potential for MDMB-4en-PINACA to cause or contribute to different clinical disorders. Conclusions: This study highlights the risk of intoxication by SCRAs when taking low-THC cannabis products. Forensic scientists, public health and public safety officials, law enforcement personnel and clinicians should be aware of the impact that these emergent SCRAs may have in their work, especially MDMB-4en-PINACA.

A Prospective Study of Intramuscular Droperidol or Olanzapine for Acute Agitation in the Emergency Department: A Natural Experiment Owing to Drug Shortages

STUDY OBJECTIVE

Intramuscular medications are commonly used to treat agitation in the emergency department (ED). The purpose of this study is to compare intramuscular droperidol and olanzapine for treating agitation.

METHODS

This was a prospective observational study of ED patients receiving intramuscular droperidol or olanzapine for acute agitation. The treating physician determined the medication and dose; however, over time drug shortages made either olanzapine (July to September 2019) or droperidol (November 2019 to March 2020) unavailable, creating a natural experiment. The primary outcome was time to adequate sedation, assessed by the Altered Mental Status Scale (AMSS), defined as time to AMSS score less than or equal to 0.

RESULTS

We analyzed 1,257 patients (median age 42 years; 73% men); 538 received droperidol (median dose 5 mg) and 719 received olanzapine (median dose 10 mg). The majority of patients (1,086; 86%) had agitation owing to alcohol intoxication. Time to adequate sedation was 16 minutes (interquartile range 10 to 30 minutes) for droperidol and 17.5 minutes (interquartile range 10 to 30 minutes) for olanzapine (absolute difference -0.7 minutes; 95% confidence interval -2.1 to 0.5 minutes). Adjusted Cox proportional hazard model analysis revealed no difference between groups in time to sedation (hazard ratio for adequate sedation for droperidol compared with olanzapine 1.12; 95% confidence interval 1.00 to 1.25). Patients receiving olanzapine were more likely to receive additional medications for sedation (droperidol 17%; olanzapine 24%; absolute difference -8% [95% confidence interval -12% to -3%]). We observed no difference between drugs regarding adverse effects except for extrapyramidal adverse effects, which were more common with droperidol (n=6; 1%) than olanzapine (n=1; 0.1%).

CONCLUSION

We found no difference in time to adequate sedation between intramuscular droperidol and olanzapine.

Randomized Double-blind Trial of Intramuscular Droperidol, Ziprasidone, and Lorazepam for Acute Undifferentiated Agitation in the Emergency Department

BACKGROUND

The optimal agent to treat acute agitation in the emergency department (ED) has not been determined. The objective of this study was to compare the effectiveness and safety of intramuscular droperidol, ziprasidone, and lorazepam for acute agitation in the ED.

METHODS

This was a randomized, double-blind trial of ED patients with acute agitation requiring parenteral sedation. The study was conducted under exception from informed consent (21 CFR 50.24) from July 2004 to March 2005. Patients were randomized to receive 5 mg of droperidol, 10 mg of ziprasidone, 20 mg of ziprasidone, or 2 mg of lorazepam intramuscularly. We recorded Altered Mental Status Scale (AMSS) scores, nasal end-tidal carbon dioxide (ETCO₂ ), and pulse oximetry (SpO₂ ) at 0, 15, 30, 45, 60, 90, and 120 minutes as well as QTc durations and dysrhythmias. Respiratory depression was defined as a change in ETCO₂ consistent with respiratory depression or SpO₂  < 90%. The primary outcome was the proportion of patients adequately sedated (AMSS ≤ 0) at 15 minutes.

RESULTS

We enrolled 115 patients. Baseline AMSS scores were similar between groups. For the primary outcome, adequate sedation at 15 minutes, droperidol administration was effective in 16 of 25 (64%) patients, compared to seven of 28 (25%) for 10 mg of ziprasidone, 11 of 31 (35%) for 20 mg of ziprasidone, and nine of 31 (29%) for lorazepam. Pairwise comparisons revealed that droperidol was more effective that the other medications, with 39% (95% confidence interval [CI] = 3% to 54%) more compared to 20 mg of ziprasidone and 33% (95% CI = 8% to 58%) more compared to lorazepam. There was no significant difference between groups in need of additional rescue sedation. Numerically, respiratory depression was lower with droperidol (3/25 [12%]) compared to 10 mg of ziprasidone (10/28 [36%]), 20 mg of ziprasidone (12/31 [39%]), or lorazepam (15/31 [48%]). One patient receiving 20 mg of ziprasidone required intubation to manage an acute subdural hematoma. No patients had ventricular dysrhythmias. QTc durations were similar in all groups.

CONCLUSIONS

Droperidol was more effective than lorazepam or either dose of ziprasidone for the treatment of acute agitation in the ED and caused fewer episodes of respiratory depression.

Urine Drug Screens in the Emergency Department: The Best Test May Be No Test at All

The manuscript purpose is to provide a resource for clinicians on the functionality and pitfalls of the rapid urine drug screen for clinical decision making. Many providers remain under-informed about the inherent inaccuracies. The rapid urine drug screen is the first, and often only, step of drug testing. In the majority of emergency departments the urine drug screen is a collection of immunoassays reliant on an interaction between the structure of a particular drug or metabolite and an antibody. Drugs in separate pharmacologic classes often have enough structural similarity to cause false positives. Conversely, drugs within the same pharmacologic class often have different enough structures that they may result in inappropriate negatives. This lack of sensitivity and specificity significantly reduces the test utility, and may cause decision-making confusion. The timing of the drug screen relative to the drug exposure also limits accuracy, as does detection threshold. Confirmatory steps following the initial immunoassay include chromatography and/or mass spectrometry. These are unavailable at many institutions and results rarely return while the patient is in the emergency department. In addition, institutional capabilities vary, even with confirmatory testing. Confirmation accuracy depends on a number of factors, including the extent of the catalog of drugs/metabolites that the facility is calibrated to detect and report. In summary, the standard emergency department urine drug screen is a test with extremely limited clinical utility with multiple properties contributing to poor sensitivity, specificity, and accuracy. The test should be used rarely, if ever, for clinical decision making.

The Psychoactive Surveillance Consortium and Analysis Network (PSCAN): the first year

BACKGROUND AND AIMS

The Psychoactive Surveillance Consortium and Analysis Network (PSCAN) is a national network of academic emergency departments (ED), analytical toxicologists and pharmacologists that collects clinical data paired with biological samples to identify and improve treatments of medical conditions arising from use of new psychoactive substances (NPS). The aim of this study was to gather clinical data with paired drug identification from NPS users who presented to EDs within PSCAN during its first year (2016-17).

DESIGN

Observational study involving patient records and biological samples.

SETTING

Seven academic emergency medical centers across the United States.

PARTICIPANTS

ED patients (n = 127) > 8 years of age with possible NPS use who were identified and enrolled in PSCAN by clinical providers or research personnel.

MEASUREMENTS

Clinical signs, symptoms and treatments were abstracted from the patients' health records. Biological samples were collected from leftover urine, serum and whole blood. Biological and drug samples, when available, were tested for drugs and drug metabolites via liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF/MS).

FINDINGS

Patients in whom synthetic opioids were detected (n = 9) showed higher rates of intubation (four of nine), impaired mental status (four of nine) and respiratory acidosis (five of nine) compared with the rest of the cohort (nine of 118, P-value < 0.05). Patients in whom synthetic cannabinoid (SC) were found (n = 27) had lower median diastolic blood pressures (70.5 versus 77 mmHg, P = 0.046) compared with the rest of the cohort. In 64 cases of single drug ingestion, benzodiazepines were administered in 25 cases and considered effective by the treating physician in 21 (84%) cases.

CONCLUSIONS

During its first year of operation, the Psychoactive Surveillance Consortium and Analysis Network captured clinical data on new classes of drugs paired with biological samples over a large geographical area in the United States. Synthetic cannabinoids were the most common new psychoactive drug identified. Synthetic opioids were associated with a high rate of intubation and respiratory acidosis.

Do Toxic Synthetic Cannabinoid Receptor Agonists Have Signature in Vitro Activity Profiles? A Case Study of AMB-FUBINACA

Recreational consumption of synthetic cannabinoid receptor agonists (SCRAs) is a growing crisis in public health in many parts of the world. AMB-FUBINACA is a member of this class of drugs and is responsible for a large proportion of SCRA-related toxicity both in New Zealand and internationally. Strikingly, little is currently known about the mechanisms by which SCRAs exert toxic effects or whether their activity through the CB1 cannabinoid receptor (the mediator of cannabinoid-related psychoactivity) is sufficient to explain clinical observations. The current study therefore set out to perform a basic molecular pharmacology characterization of AMB-FUBINACA (in comparison to traditional research cannabinoids CP55,940, WIN55,212-2, and Δ9-THC) in fundamental pathways of receptor activity, including cAMP inhibition, pERK activation, ability to drive CB1 internalization, and ability to induce translocation of β-arrestins-1 and -2. Activity pathways were then compared by operational analysis to indicate whether AMB-FUBINACA may be a biased ligand. Results revealed that AMB-FUBINACA is highly efficacious and potent in all pathways assayed. However, surprisingly, bias analysis suggested that Δ9-THC, not AMB-FUBINACA, may be a biased ligand, with it being less active in both arrestin pathways than predicted by the activity of the other ligands tested. These data may help predict molecular characteristics of SCRAs. However, more research is required to determine whether these molecular effects manifest in toxicity at tissue/system level.