Alprazolam misuse: Analysis of French Addictovigilance Network data from 2011 to 2020.

OBJECTIVES: Alprazolam, a high-potency and short-acting anxiolytic benzodiazepine, is one of the most misused benzodiazepines in France. In the context of various reports on alprazolam misuse during the COVID-19 pandemic, the objective of this study was to assess alprazolam abuse potential by analyzing French addictovigilance and international data. METHODS: Data collected from 2011 to 2020 using the following epidemiological tools of the French Addictovigilance Network were analyzed: spontaneous reports (SRs), OPPIDUM (addiction care center data), OSIAP (falsified prescriptions), DRAMES (substance-related deaths), and chemical submission surveys. Moreover, the VigiBase™ database was analyzed to evaluate alprazolam abuse liability worldwide. RESULTS: During the study period, 675 SRs concerning alprazolam misuse were recorded (sex ratio: Ì´1; median age: 39 years). The desired effects were intensification of the therapeutic anxiolytic effect, euphoric effect, and management of substance withdrawal. Alprazolam was the third and first benzodiazepine listed in OPPIDUM and OSIAP surveys. Analysis of the SR and OPPIDUM data showed a recent increase in the alprazolam-opioid combination. In DRAMES data, alprazolam was directly linked to 11 deaths (associated with opioids in 10/11). VigiBase™ data analysis highlighted that France was the third country with the most cases of alprazolam misuse. The disproportionality analysis showed that in France, alprazolam was associated with higher risk of misuse and dependence compared with other benzodiazepines: reporting odds ratio=1.43, (95% CI: 1.04-1.95) and=1.97 (95% CI:1.50-2.59), respectively. CONCLUSIONS: This study highlighted an increase in various signals of alprazolam abuse in France, and an increased use of the alprazolam-opioid combination that was also linked to most of the recorded alprazolam-linked deaths. These signals have been reported also in the international literature, and should be thoroughly investigated.

French national addictovigilance follow-up of zolpidem between 2014 and 2020: evolution of drug abuse, misuse and dependence before and after the regulatory change.

BACKGROUND: Since the appearance of zolpidem on the market, the occurrence of serious cases of abuse, misuse and dependence have come to the attention of authorities. In view of the increase in the number and severity of cases among zolpidem users and the predominant presence of zolpidem in falsified prescriptions, the French Health Authorities implemented part of the narcotics regulation for zolpidem in April 2017. The objective of this article was to describe the evolution of the abuse, dependence and misuse of zolpidem. METHODS: We used three data sources: (i) zolpidem is a reimbursable and strictly prescription drug in France. Medic'AM is a public database that indicates the number of tablets reimbursed each month in France for each reimbursable drug. This database has been analyzed as a proxy of the exposure of the French population to zolpidem; (ii) all French cases of drug dependence or abuse reported by health professionals (regulatory obligation) and (iii) an epidemiological tool based on the surveillance of falsified prescriptions over two periods: the 3-year period before the regulatory measure (2014-16) and the 3-year period after the regulatory measure (2018-20). RESULTS: This regulatory change had two immediate consequences: a sharp decline in falsified prescriptions and a decrease of ∼57% between the two study periods in the zolpidem reimbursement data. Markers of problematic consumption remained after the regulatory change with worsening cases, particularly for people who were genuinely dependent and/or had comorbidities or misusers for whom zolpidem was the substance of interest, whose proportion increased significantly in the addictovigilance notification system, from 43.6% (N = 107) to 59.3% (N = 127) (P < 0.01). CONCLUSIONS: Further monitoring is needed in light of these persistent markers of problematic consumption.

[Therapeutic drug monitoring of clozapine]. / Suivi thérapeutique pharmacologique de la clozapine.

Clozapine is a prototypical atypical antipsychotic used to treat severe schizophrenia and for which a therapeutic drug monitoring (TDM) is quite commonly proposed. Clozapine is rapidly absorbed (maximum concentration reached within 1 to 4hours), and is extensively metabolized in the liver by CYP1A2 to an active metabolite (and to a lesser extent, to inactive metabolites via other enzymes). Its half-life is 8 to 16h. A therapeutic range has been proposed for clozapine as some studies have reported both a relationship between low plasmatic concentrations and resistance to treatment (threshold level is likely between 250 and 400µg/L), and a relationship between high plasmatic concentrations and an increase in the occurrence of toxicity (alert level=1000µg/L). Given the data obtained in different studies, the TDM was evaluated for this molecule, to recommended.

[Therapeutic drug monitoring of olanzapine]. / Suivi thérapeutique pharmacologique de l'olanzapine.

Olanzapine, atypical antipsychotic, is used to treat schizophrenia and bipolar disorder. Its therapeutic drug monitoring (TDM) is quite commonly done. Olanzapine is well absorbed orally (bioavailability: 85 %), with peak plasma occurring between 4 and 6hours after oral administration. It is extensively metabolized by different hepatic enzymes (including CYP1A2 and CYP2D6 isoforms) to a large number of inactive metabolites, and its half-life is between 30 and 60hours. No specific therapeutic range, or threshold concentration could not be a consensus, but the higher intra- and interindividual variability, as well as the existence of studies suggesting a correlation between circulating concentrations of olanzapine and occurrence of therapeutic relapse or toxic phenomena appear to justify the STP for this molecule. Given these data, the interest of the STP was evaluated for this molecule to: recommended with therapeutic window of 20µg/L to 80µg/L.

Dissecting the Role of Thyrotropin in the DNA Damage Response in Human Thyrocytes after 131I, γ Radiation and H2O2.

BACKGROUND: The early molecular events in human thyrocytes after 131I exposure have not yet been unravelled. Therefore, we investigated the role of TSH in the 131I-induced DNA damage response and gene expression in primary cultured human thyrocytes. METHODS: Following exposure of thyrocytes, in the presence or absence of TSH, to 131I (ß radiation), γ radiation (3 Gy), and hydrogen peroxide (H2O2), we assessed DNA damage, proliferation, and cell-cycle status. We conducted RNA sequencing to profile gene expression after each type of exposure and evaluated the influence of TSH on each transcriptomic response. RESULTS: Overall, the thyrocyte responses following exposure to ß or γ radiation and to H2O2 were similar. However, TSH increased 131I-induced DNA damage, an effect partially diminished after iodide uptake inhibition. Specifically, TSH increased the number of DNA double-strand breaks in nonexposed thyrocytes and thus predisposed them to greater damage following 131I exposure. This effect most likely occurred via Gα q cascade and a rise in intracellular reactive oxygen species (ROS) levels. ß and γ radiation prolonged thyroid cell-cycle arrest to a similar extent without sign of apoptosis. The gene expression profiles of thyrocytes exposed to ß/γ radiation or H2O2 were overlapping. Modulations in genes involved in inflammatory response, apoptosis, and proliferation were observed. TSH increased the number and intensity of modulation of differentially expressed genes after 131I exposure. CONCLUSIONS: TSH specifically increased 131I-induced DNA damage probably via a rise in ROS levels and produced a more prominent transcriptomic response after exposure to 131I.

Genetic Analysis of Mu and Kappa Opioid Receptor and COMT Enzyme in Cancer Pain Tunisian Patients Under Opioid Treatment.

BACKGROUND: Pain and its opioid treatments are complex measurable traits. Responses to morphine in terms of pain control is likely to be determined by many factors, including the underlying pain sensitivity of the patient, along with nature and extent of the painful process, concomitant medications, genetic and other clinical and environmental factors. This study investigated genetic polymorphisms implicated in the inter-individual pain response variability to opioid treatment in the Tunisian population. METHODS: This prospective association study investigated seven variations in the OPRM1, OPRK1 and COMT gene, which encode Mu and KAPPA opioid receptors, and Catechol-O-methyltransferase enzyme respectively, in a cohort of 129 Tunisian cancer pain patients under oral morphine treatment. Genotyping was performed by simple probe probes on Light Cyler for rs17174629, rs1799972, rs1799971, rs1051659, rs1051660 and rs4680 and by PCR assay for the indel in the promoter region of OPRK1 (rs35566036). A statistical associations study between dose (continuous), dose escalation (yes/no) and SNP or haplotypes were investigated using linear multiple regressions and logistic regressions respectively adjusted on metastases and pain covariates in the R software. RESULTS: We detected significant association of the rs1051660 adjusted on metastasis and pain (P=0.02), no other association has been detected between the 7 polymorphisms screened and the dose of morphine needed for pain relief. CONCLUSION: This can be explained by the strong genetic heterogeneity in the cosmopolitan areas where our patients were recruited for this study, compared to more homegenous population recruited in other studies.

Agomelatine: a new opportunity to reduce neuropathic pain-preclinical evidence.

Antidepressants are first-line treatments of neuropathic pain but not all these drugs are really effective. Agomelatine is an antidepressant with a novel mode of action, acting as an MT1/MT2 melatonergic receptor agonist and a 5-HT2C receptor antagonist that involves indirect norepinephrine release. Melatonin, serotonin, and norepinephrine have been involved in the pathophysiology of neuropathic pain. Yet, no study has been conducted to determine agomelatine effects on neuropathic pain in animal models. Using 3 rat models of neuropathic pain of toxic (oxaliplatin/OXA), metabolic (streptozocin/STZ), and traumatic (sciatic nerve ligation/CCI [chronic constriction nerve injury]) etiologies, we investigated the antihypersensitivity effect of acute and repeated agomelatine administration. We then determined the influence of melatonergic, 5-HT2C, α-2 and ß-1/2 adrenergic receptor antagonists in the antihypersensitivity effect of agomelatine. The effect of the combination of agomelatine + gabapentin was evaluated using an isobolographic approach. In STZ and CCI models, single doses of agomelatine significantly and dose dependently reduced mechanical hypersensitivity. After daily administrations for 2 weeks, this effect was confirmed in the CCI model and agomelatine also displayed a marked antihypersensitivity effect in the OXA model. The antihypersensitivity effect of agomelatine involved melatonergic, 5-HT2C, and α-2 adrenergic receptors but not beta adrenoceptors. The isobolographic analysis demonstrated that the combination of agomelatine + gabapentin had additive effects. Agomelatine exerts a clear-cut antihypersensitivity effect in 3 different neuropathic pain models. Its effect is mediated by melatonergic and 5-HT2C receptors and, although agomelatine has no affinity, also by α-2 adrenergic receptors. Finally, agomelatine combined with gabapentin produces an additive antihypersensitivity effect.

Increasing spinal 5-HT2A receptor responsiveness mediates anti-allodynic effect and potentiates fluoxetine efficacy in neuropathic rats. Evidence for GABA release.

Antidepressants are one of the first line treatments for neuropathic pain but their use is limited by the incidence and severity of side effects of tricyclics and the weak effectiveness of selective serotonin reuptake inhibitors (SSRIs). Serotonin type 2A (5-HT2A) receptors interact with PDZ proteins that regulate their functionality and SSRI efficacy to alleviate pain. We investigated whether an interfering peptide (TAT-2ASCV) disrupting the interaction between 5-HT2A receptors and associated PDZ proteins would improve the treatment of traumatic neuropathic allodynia. Tactile allodynia was assessed in spinal nerve ligation-induced neuropathic pain in rats using von Frey filaments after acute treatment with TAT-2ASCV and/or 5-HT2A receptor agonist, alone or in combination with repeated treatment with fluoxetine. In vivo microdialysis was performed in order to examine the involvement of GABA in TAT-2ASCV/fluoxetine treatment-associated analgesia. TAT-2ASCV (100ng, single i.t. injection) improved SNL-induced tactile allodynia by increasing 5-HT2A receptor responsiveness to endogenous 5-HT. Fluoxetine alone (10mg/kg, five i.p. injections) slightly increased tactile thresholds and its co-administration with TAT-2ASCV (100ng, single i.t. injection) further enhanced the anti-allodynic effect. This effect depends on the integrity of descending serotonergic bulbospinal pathways and spinal release of GABA. The anti-allodynic effect of fluoxetine can be enhanced by disrupting 5-HT2A receptor-PDZ protein interactions. This enhancement depends on 5-HT2A receptor activation, spinal GABA release and GABAA receptor activation.

Pharmacogenomics in pain treatment.

The experience of chronic pain is one of the commonest reasons for seeking medical attention, being a major issue in clinical practice. While pain is a universal experience, only a small proportion of people who felt pain develop pain syndromes. In addition, painkillers are associated with wide inter-individual variability in the analgesic response. This may be partly explained by the presence of single nucleotide polymorphisms in genes encoding molecular entities involved in pharmacodynamics and pharmacokinetics. However, uptake of this information has been slow due in large part to the lack of robust evidences demonstrating clinical utility. Furthermore, novel therapies, including targeting of epigenetic changes and gene therapy-based approaches are further broadening future options for the treatment of chronic pain. The aim of this article is to review the evidences behind pharmacogenetics (PGx) to individualize therapy (boosting the efficacy and minimizing potential toxicity) and genes implicated in pain medicine, in two parts: (i) genetic variability with pain sensitivity and analgesic response; and (ii) pharmacological concepts applied on PGx.

Association of the OPRM1 and COMT genes' polymorphisms with the efficacy of morphine in Tunisian cancer patients: Impact of the high genetic heterogeneity in Tunisia?

BACKGROUND: Genetic causes for inter-individual variability response to opioids are clinical difficulties for treatment efficiency. The aim of the present study was to investigate the possible association of opioid treatment outcome with single nucleotide polymorphisms (SNPs) in the mµ opioid receptor (OPRM1) and catechol-o-methyltransferase (COMT) genes, in Tunisian cancer pain patients. METHODS: We genotyped one hundred and twenty-nine cancer patients treated with different doses of morphine for 3 SNPs in OPRM1 gene (rs17174629, rs1799972 and rs1799971) and one in the COMT gene (rs4680). Associations between dose (continuous), dose escalation (yes/no) and SNP or haplotypes were investigated. RESULTS: Unlike other studies on Caucasian and Chinese populations, no significant association were found between the 4 polymorphisms screened and the dose of morphine needed for pain relief. CONCLUSION: This result can be explained by the genetic heterogeneity and cosmopolitan areas of our Tunisian patients compared to the others homogenous population.

[Practical information for therapeutic drug monitoring of the most common compounds]. / Éléments de l'interprétation et du dialogue clinico-biologique pour quelques paramètres usuels de pharmacologie-toxicologie.

This article reports the main information for the interpretation of blood concentrations of most common drugs measured in pharmacology-toxicology departments: acetaminophen, amikacin, carbamazepine, digoxin, gentamicin, lithium, methotrexate, phenobarbital, phenytoin and valproic acid.

Fully automated semi-quantitative toxicological screening in three biological matrices using turbulent flow chromatography/high resolution mass spectrometry.

BACKGROUND: In clinical and forensic toxicology, fast and specific methods are needed for the screening of different classes of drugs. A complete general unknown screening procedure was developed using turbulent flow chromatography with electrospray ionization and Orbitrap mass spectrometry. METHODS: After protein precipitation, samples were injected directly into the turbulent flow chromatographic system and analyzed with an Orbitrap mass spectrometer. The Exactive® operated in positive and negative modes with alternated high collision dissociation in order to obtain characteristic fragments. We built a library containing 616 compounds by analyzing a reference standard for all the molecules. RESULTS: Identification was based on retention time, accurate measured mass, isotopic pattern and presence of specific fragments. For each substance, we set a calibration range encompassing infra-therapeutic, therapeutic, supra-therapeutic and toxic concentrations in order to generate semi-quantitative result. For 65% of the components, the limit of detection was below 5 ng/mL. The validation process showed the approach to be selective, sensitive, accurate and precise. CONCLUSION: The method has been accredited by COFRAC (French Accreditation Committee) according to the ISO 15189 standard. Applicability was successfully tested by analyzing authentic serum, urine and whole blood samples.

Prevention of oxaliplatin-induced peripheral neuropathy by a polyamine-reduced diet-NEUROXAPOL: protocol of a prospective, randomised, controlled, single-blind and monocentric trial.

INTRODUCTION: Oxaliplatin remains the most widely used chemotherapeutic agent for treating advanced colorectal cancer but its efficacy is hampered by dose-limiting neurotoxicity manifested by a painful polyneuropathy. Oxaliplatin-induced peripheral neuropathy (OIPN) is characterised by acute and transient cold hyperaesthesia in the hours and days following oxaliplatin infusion (>90% of patients), but also by retarded chronic neuropathy due to the repetition of chemotherapy cycles (30-50% of patients). OIPN impairs the health-related quality of life (HRQOL) of patients and no preventive or curative strategies have as yet proven effective. A polyamine-reduced diet (PRD) has recently demonstrated its efficacy to prevent OIPN in animals without adverse effects. METHODS AND ANALYSIS: The NEUROXAPOL trial is a prospective, randomised, controlled, single-blind, monocentric and interventional study. This trial is aimed at evaluating the efficacy and feasibility of a PRD compared to a normal polyamine containing diet to prevent OIPN in patients treated by oxaliplatin-based chemotherapy. Patients (n=40 per group) will be randomly assigned to receive either a PRD or a normal diet before and during the chemotherapy regimen. The main objectives are to improve the cold pain thresholds, neuropathic pain symptoms, comorbidities (anxiety and depression) and HRQOL of patients. The primary end point is the assessment of cold pain thresholds 2 weeks after the third cycle of chemotherapy. The secondary end points are the evaluation of thermal pain thresholds, the grade of neuropathy, neuropathic pain, symptoms of anxiety and depression and HRQOL, until the 12th cycle of chemotherapy. ETHICS AND DISSEMINATION: The study was approved by an independent medical ethics committee 1 (CPP Sud Est 1, Saint Etienne, France) and registered by the competent French authority (ANSM, Saint Denis, France). The results will be disseminated in a peer-reviewed journal and presented at international congresses. TRIAL REGISTRATION NUMBER: NCT01775449.

Buccal acetaminophen provides fast analgesia: two randomized clinical trials in healthy volunteers.

BACKGROUND: Acetaminophen (APAP) by oral or intravenous (iv) routes is used for mild to moderate pain but may take time to be effective. When fast relief is required and/or oral or iv routes are not available because of the patient's condition, the transmucosal route may be an alternative. METHODOLOGY: A new transmucosal/buccal (b) pharmaceutical form of APAP dissolved in 50% wt alcohol is compared with other routes of administration. Two consecutive randomized, crossover, double-blind clinical trials (CT1: NCT00982215 and CT2: NCT01206985) included 16 healthy volunteers. CT1 compared the pharmacology of 250 mg bAPAP with 1 g iv APAP. CT2 compared the pharmacodynamics of 125 mg bAPAP with 1 g iv and 125 mg sublingual (s) APAP. Mechanical pain thresholds are recorded in response to mechanical stimuli applied on the forearm several times during 120 minutes. The objective is to compare the time of onset of antinociception and the antinociception (area under the curve) between the routes of administration with analysis of variance (significance P<0.05). RESULTS: bAPAP has a faster time of antinociception onset (15 minutes, P<0.01) and greater antinociception at 50 minutes (P<0.01, CT1) and 30 minutes (P<0.01, CT2) than ivAPAP and sAPAP. All routes are similar after 50 minutes. CONCLUSION: bAPAP has a faster antinociceptive action in healthy volunteers. This attractive alternative to other routes would be useful in situations where oral or iv routes are not available. This finding must now be confirmed in patients suffering from acute pain of mild and moderate intensity.

Fatty acid amide hydrolase-dependent generation of antinociceptive drug metabolites acting on TRPV1 in the brain.

The discovery that paracetamol is metabolized to the potent TRPV1 activator N-(4-hydroxyphenyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (AM404) and that this metabolite contributes to paracetamol's antinociceptive effect in rodents via activation of TRPV1 in the central nervous system (CNS) has provided a potential strategy for developing novel analgesics. Here we validated this strategy by examining the metabolism and antinociceptive activity of the de-acetylated paracetamol metabolite 4-aminophenol and 4-hydroxy-3-methoxybenzylamine (HMBA), both of which may undergo a fatty acid amide hydrolase (FAAH)-dependent biotransformation to potent TRPV1 activators in the brain. Systemic administration of 4-aminophenol and HMBA led to a dose-dependent formation of AM404 plus N-(4-hydroxyphenyl)-9Z-octadecenamide (HPODA) and arvanil plus olvanil in the mouse brain, respectively. The order of potency of these lipid metabolites as TRPV1 activators was arvanil = olvanil>>AM404> HPODA. Both 4-aminophenol and HMBA displayed antinociceptive activity in various rodent pain tests. The formation of AM404, arvanil and olvanil, but not HPODA, and the antinociceptive effects of 4-aminophenol and HMBA were substantially reduced or disappeared in FAAH null mice. The activity of 4-aminophenol in the mouse formalin, von Frey and tail immersion tests was also lost in TRPV1 null mice. Intracerebroventricular injection of the TRPV1 blocker capsazepine eliminated the antinociceptive effects of 4-aminophenol and HMBA in the mouse formalin test. In the rat, pharmacological inhibition of FAAH, TRPV1, cannabinoid CB1 receptors and spinal 5-HT3 or 5-HT1A receptors, and chemical deletion of bulbospinal serotonergic pathways prevented the antinociceptive action of 4-aminophenol. Thus, the pharmacological profile of 4-aminophenol was identical to that previously reported for paracetamol, supporting our suggestion that this drug metabolite contributes to paracetamol's analgesic activity via activation of bulbospinal pathways. Our findings demonstrate that it is possible to construct novel antinociceptive drugs based on fatty acid conjugation as a metabolic pathway for the generation of TRPV1 modulators in the CNS.

Measurement of imatinib uptake by flow cytometry.

One of the essential parameters of targeted therapy efficiency in cancer treatment is the amount of drug reaching the therapeutic target area. Imatinib (IM) was the first specifically targeted drug to be developed and has revolutionized the treatment of patients with chronic myeloid leukemia (CML). To evaluate cellular uptake of IM, we developed a method based on the chemical structure of the molecule and using the natural UV fluorescence that we quantified by flow cytometry. In two CML cell lines, we obtained a satisfactory relationship between intracellular IM (ICIM) levels and media concentrations, and we found a strong correlation between ICIM at 1 h and IM efficacy at 24 h, demonstrating that ICIM at 1 h might be a relevant predictive parameter of cell sensitivity. Our method was more sensitive than the standard physicochemical method. We applied our method to primary cells and found cell morphology-dependent IM accumulation. Moreover, in CML cells from patients at diagnosis, IM accumulation was heterogeneous. In all cases, ICIM at the single-cell level was much higher than in culture media arguing in favor of a predominantly active uptake process. We developed a simple method directly applicable to primary cells that has shown two major advantages: only a small number of cells are required, and cell subsets can be identified according to morphological criteria and/or the presence of particular antigenic sites. This method provides a new tool to assess CML cell sensitivity to IM, and ICIM levels in native CML cells could be used to monitor therapeutic response.

[Level of evidence for therapeutic drug monitoring of itraconazole]. / Niveau de preuve du suivi thérapeutique pharmacologique de l'itraconazole.

Itraconazole is a triazole antifungal agent that is active against Aspergillus, histoplasmosis, and rare fungal infections. Itraconazole exhibit marked variability in drug concentration as a result of inconsistent absorption, metabolism, or interaction with concomitant medications. Preclinical and clinical data have exhibited a relationship between serum concentrations and treatment efficacy or toxicity, thus therapeutic drug monitoring (TDM) of itraconazole is largely used to optimise therapy. The analysis of bibliographic data demonstrate that, even if the utility of itraconazole's TDM has not been proved by randomized controlled trial or pharmaco-economics studies, it could be useful for managing an absence of response or a drug-drug interactions, or interpreting an adverse effect. However, the interest of this monitoring was proved only in some populations of patients (neutropenics or AIDS patients) so its level of proof varies between levels "potentially useful" and "recommended".