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Extensive preclinical data implicate corticotropin-releasing hormone (CRH), acting through its CRH1 receptor, in stress- and dependence-induced alcohol seeking. We evaluated pexacerfont, an orally available, brain penetrant CRH1 antagonist for its ability to suppress stress-induced alcohol craving and brain responses in treatment seeking alcohol-dependent patients in early abstinence. Fifty-four anxious alcohol-dependent participants were admitted to an inpatient unit at the NIH Clinical Center, completed withdrawal treatment, and were enrolled in a double-blind, randomized, placebo-controlled study with pexacerfont (300 mg/day for 7 days, followed by 100 mg/day for 23 days). After reaching steady state, participants were assessed for alcohol craving in response to stressful or alcohol-related cues, neuroendocrine responses to these stimuli, and functional magnetic resonance imaging (fMRI) responses to alcohol-related stimuli or stimuli with positive or negative emotional valence. A separate group of 10 patients received open-label pexacerfont following the same dosing regimen and had cerebrospinal fluid sampled to estimate central nervous system exposure. Pexacerfont treatment had no effect on alcohol craving, emotional responses, or anxiety. There was no effect of pexacerfont on neural responses to alcohol-related or affective stimuli. These results were obtained despite drug levels in cerebrospinal fluid (CSF) that predict close to 90% central CRH1 receptor occupancy. CRH1 antagonists have been grouped based on their receptor dissociation kinetics, with pexacerfont falling in a category characterized by fast dissociation. Our results may indicate that antagonists with slow offset are required for therapeutic efficacy. Alternatively, the extensive preclinical data on CRH1 antagonism as a mechanism to suppress alcohol seeking may not translate to humans.

Background: DBS are an increasingly common clinical matrix., Methods & Results: Sensitive and specific methods for DBS and venous blood cocaine and metabolite detection by LC-HRMS and 2D GC-MS, respectively, were validated to examine correlation between concentrations following controlled intravenous cocaine administration. Linear ranges from 1 to 200 µg/l were achieved, with acceptable bias and imprecision. Authentic matched specimens' (392 DBS, 97 venous blood) cocaine and benzoylecgonine concentrations were qualitatively similar, but DBS had much greater variability (21.4-105.9 %CV) and were lower than in blood., Conclusion: DBS offer advantages for monitoring cocaine intake; however, differences between capillary and venous blood and DBS concentration variability must be addressed., Competing Interests: Financial & competing interests disclosure This work was supported by the Intramural Research Program (IRP), National Institute on Drug Abuse (NIDA), NIH. JL da Costa received a postdoctoral fellowship from Brazilian National Counsel of Technological and Scientific Development (CNPq) to conduct this research. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.

Background: Currently, urine and blood are the only matrices authorized for antidoping testing by the World Anti-Doping Agency (WADA). Although the usefulness of urine and blood is proven, issues remain for monitoring some drug classes and for drugs prohibited only in competition. The alternative matrix oral fluid (OF) may offer solutions to some of these issues. OF collection is easy, noninvasive, and sex neutral and is directly observed, limiting potential adulteration, a major problem for urine testing. OF is used to monitor drug intake in workplace, clinical toxicology, criminal justice, and driving under the influence of drugs programs and potentially could complement urine and blood for antidoping testing in sports., Content: This review outlines the present state of knowledge and the advantages and limitations of OF testing for each of the WADA drug classes and the research needed to advance OF testing as a viable alternative for antidoping testing., Summary: Doping agents are either prohibited at all times or prohibited in competition only. Few OF data from controlled drug administration studies are available for substances banned at all times, whereas for some agents prohibited only in competition, sufficient data may be available to suggest appropriate analytes and cutoffs (analytical threshold concentrations) to identify recent drug use. Additional research is needed to characterize the disposition of many banned substances into OF; OF collection methods and doping agent stability in OF also require investigation to allow the accurate interpretation of OF tests for antidoping monitoring.

Background: Synthetic cannabinoids (SC) are widely-abused cannabimimetic drugs that do not screen positive in traditional cannabinoids immunoassays, making detection difficult., Methods and Results: The first commercially-available immunoassay for urinary SC was validated. Limits of detection (5-20 µg/L), imprecision (<13.1% intra-, <37.7% inter-assay), and cross-reactivity profiles of 22 SC and 37 metabolites were obtained. A large negative bias (-80.8 to -28.0%) was observed. Sensitivity (98.3%), specificity (48.1%) and efficiency (53.9%) were determined from screening 20,017 urine specimens and confirming 1432 presumptive positive and 1069 selected negative specimens by LC-MS/MS. Cutoff optimization improved performance to 87.6% sensitivity, 85.2% specificity, and 85.4% efficiency., Conclusion: This high-throughput urine SC assay has good sensitivity and improved specificity and efficiency at modified cutoff concentrations.

Background: Oral Δ(9)-tetrahydrocannabinol (THC) is effective for attenuating cannabis withdrawal and may benefit treatment of cannabis use disorders. Oral fluid (OF) cannabinoid testing, increasing in forensic and workplace settings, could be valuable for monitoring during cannabis treatment., Methods: Eleven cannabis smokers resided on a closed research unit for 51 days and received daily 0, 30, 60, and 120 mg of oral THC in divided doses for 5 days. There was a 5-puff smoked cannabis challenge on the fifth day. Each medication session was separated by 9 days of ad libitum cannabis smoking. OF was collected the evening before and throughout oral THC sessions and analyzed by 2-dimensional GC-MS for THC, cannabidiol (CBD), cannabinol (CBN), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH)., Results: During all oral THC administrations, THC OF concentrations decreased to ≤ 78.2, 33.2, and 1.4 μg/L by 24, 48, and 72 h, respectively. CBN also decreased over time, with concentrations 10-fold lower than THC, with none detected beyond 69 h. CBD and 11-OH-THC were rarely detected, only within 19 and 1.6 h after smoking, respectively. THCCOOH OF concentrations were dose dependent and increased over time during 120-mg THC dosing. After cannabis smoking, THC, CBN, and THCCOOH concentrations showed a significant dose effect and decreased significantly over time., Conclusions: Oral THC dosing significantly affected OF THCCOOH but minimally contributed to THC OF concentrations; prior ad libitum smoking was the primary source of THC, CBD, and CBN. Higher cannabinoid concentrations following active oral THC administrations vs placebo suggest a compensatory effect of THC tolerance on smoking topography.

Synthetic cathinones are novel stimulants derived from cathinone, with amphetamines or cocaine-like effects, often labeled "not for human consumption" and considered "legal highs". Emergence of these new designer drugs complicate interpretation of forensic and clinical cases, with introduction of many new analogs designed to circumvent legislation and vary effects and potencies. We developed a method for the simultaneous quantification of 28 synthetic cathinones, including four metabolites, in urine by liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS). These cathinones include cathinone, methcathinone, and synthetic cathinones position-3'-substituted, N-alkyl-substituted, ring-substituted, methylenedioxy-substituted, and pyrrolidinyl-substituted. One mL phosphate buffer pH 6 and 25 μL IStd solution were combined with 0.25 mL urine, and subjected to solid phase cation exchange extraction (SOLA SCX). The chromatographic reverse-phase separation was achieved with a gradient mobile phase of 0.1 % formic acid in water and in acetonitrile in 20 min. We employed a Q Exactive high resolution mass spectrometer, with compounds identified and quantified by target-MSMS experiments. The assay was linear from 0.5-1 to 100 μg/L, with limits of detection of 0.25-1 μg/L. Imprecision (n = 20) was <15.9 % and accuracy (n = 20) 85.2-118.1 %. Extraction efficiency was 78.9-116.7 % (CV 1.4-16.7 %, n = 5), process efficiency 57.7-104.9 %, and matrix effects from -29.5 % to 1.5 % (CV 1.9-13.1 %, n = 10). Most synthetic cathinones were stable at 4 °C for 72 h (n = 27) and after 3 freeze-thaw cycles (n = 26), but many (n = 19) were not stable at room temperature for 24 h (losses up to -67.6 %). The method was applied to authentic urine specimens from synthetic cathinone users. This method provides a comprehensive confirmation method for 28 synthetic cathinones in urine, with good selectivity and specificity.

Oral fluid (OF) is an alternative biological matrix for monitoring cannabis intake in drug testing, and drugged driving (DUID) programs, but OF cannabinoid test interpretation is challenging. Controlled cannabinoid administration studies provide a scientific database for interpreting cannabinoid OF tests. We compared differences in OF cannabinoid concentrations from 19 h before to 30 h after smoking a 6.8% THC cigarette in chronic frequent and occasional cannabis smokers. OF was collected with the Statsure Saliva Sampler™ OF device. 2D-GC-MS was used to quantify cannabinoids in 357 OF specimens; 65 had inadequate OF volume within 3 h after smoking. All OF specimens were THC-positive for up to 13.5 h after smoking, without significant differences between frequent and occasional smokers over 30 h. Cannabidiol (CBD) and cannabinol (CBN) had short median last detection times (2.5-4 h for CBD and 6-8 h for CBN) in both groups. THCCOOH was detected in 25 and 212 occasional and frequent smokers' OF samples, respectively. THCCOOH provided longer detection windows than THC in all frequent smokers. As THCCOOH is not present in cannabis smoke, its presence in OF minimizes the potential for false positive results from passive environmental smoke exposure, and can identify oral THC ingestion, while OF THC cannot. THC ≥ 1 μg/L, in addition to CBD ≥ 1 μg/L or CBN ≥ 1 μg/L suggested recent cannabis intake (≤13.5 h), important for DUID cases, whereas THC ≥ 1 μg/L or THC ≥ 2 μg/L cutoffs had longer detection windows (≥30 h), important for workplace testing. THCCOOH windows of detection for chronic, frequent cannabis smokers extended beyond 30 h, while they were shorter (0-24 h) for occasional cannabis smokers.