Brief intervention for chronic liver disease patients with alcohol use disorder in a hepatology outpatient unit: Effects and limitations.

AIM: It is not uncommon to encounter outpatients in the hepatology department with harmful alcohol habits. When treating such chronic liver disease (CLD) patients, an adequate intervention method for harm reduction of alcohol use, such as brief intervention (BI) or BI and nalmefene, should be considered. This study aimed to elucidate the clinical effectiveness of BI for CLD patients affected by harmful alcohol use. METHODS: From June 2021 to 2023, 123 Japanese CLD outpatients (hepatitis B virus : hepatitis C virus : alcoholic liver disease : others = 32:18:42:31) with an Alcohol Use Disorders Identification Test (AUDIT) score of ≥8 at the initial interview and a repeat interview with AUDIT 9 months later were enrolled. Clinical features related to patient behavior following the initial AUDIT interview were retrospectively evaluated, and compared between patients without and with BI treatment. RESULTS: For the non-BI and BI groups, baseline AUDIT score (median 10 [interquartile range (IQR) 9-13] vs. 12 [IQR 10-17], p = 0.016) and relative change in AUDIT score (median 0 [IQR -3 to 2] vs. -3 [IQR -7 to 0], p < 0.01) showed significant differences, whereas there was no significant difference between the groups for AUDIT score at the time of the second interview (p = 0.156). Following BI, significant improvements were observed for items 1, 2, 3, 4, 5, 8, and 10 of AUDIT (each p < 0.05). CONCLUSION: Patients with an alcohol use disorder as well as those with alcohol dependency who received BI showed a significant decline in AUDIT score, although the score of the follow-up AUDIT indicated continued alcohol use disorder. In addition to BI, medication with nalmefene should be considered, based on individual factors.

Respiratory Depression Associated with Opioids: A Narrative Review.

OPINION: All opioids have a risk of causing respiratory depression and reduced cerebral circulation. Fentanyl has the greatest risk of causing both. This is particularly a concern when combined with illicit opioids such as diamorphine (also known as heroin). Fentanyl should not be used as a frontline potent opioid due its significant risks. Buprenorphine, a schedule III opioid, morphine, or hydromorphone is preferred, followed by oxycodone, which has a significant risk of abuse relative to buprenorphine and morphine. Although all opioids were equally effective in producing analgesia, the relative safety of each opioid is no longer a secondary concern when prescribing. In the face of an international opioid epidemic, clinicians need to choose opioid analgesics safely, wisely, and carefully.

Different doses of nalmefene combined with hydromorphone hydrochloride for postoperative analgesia after colorectal surgery: a randomized controlled study.

BACKGROUND: Hydromorphone hydrochloride has a satisfactory postoperative analgesic effect for patients with colorectal cancer but is accompanied by a relatively high incidence of adverse events. Low-doses of naloxone combined with opioids for patient-controlled analgesia can reduce the incidence of drug-related adverse events. Nalmefene is a more selective opioid receptor antagonist than naloxone. The aim of this study was to determine the impact of low-doses of nalmefene on the analgesic effect and incidence of adverse events of patients with hydromorphone patient-controlled analgesia (PCA) undergoing colorectal radical surgery. METHODS: Ninety-nine patients undergoing elective laparoscopic or hand-assisted laparoscopic radical surgery under general anaesthesia were randomly divided into three groups. Group N1 received hydromorphone hydrochloride 0.15 mg/kg + nalmefene 2 µg/kg; Group N2 received hydromorphone hydrochloride 0.15 mg/kg + nalmefene 0.5 µg/kg; and the control group (Group C) received hydromorphone hydrochloride 0.15 mg/kg. All medications were diluted to 100 ml with normal saline. The primary outcome was pain intensity at 12 h after surgery; the secondary outcomes were the occurrence of nausea, vomiting and pruritus and the total analgesic consumption of the PCA pump at 1 h, 6 h, 12 h, 24 and 48 h after surgery. RESULTS: The NRS scores of Group N1 (2 µg/kg) were significantly lower than those of Group C (P = 0.025), and no difference was found between group N2 and group C (P > 0.05). Among the three groups, the NRS scores of Group N1 (2 µg/kg) were significantly lower than those of Group C at 12 h (P = 0.01) and 48 h (P = 0.01) postoperatively. Compared with 12 h postoperatively, the NRS scores were lower at 24 h postoperatively in Group N1 and Group C (P < 0.05) and significantly lower at 48 h postoperatively in all three groups (P < 0.001). There was a significant difference in the incidence of pruritus among the three groups (P = 0.036). CONCLUSIONS: Nalmefene at a dosage of 2 µg/kg enhances the postoperative analgesic effect of hydromorphone hydrochloride and reduces the occurrence of postoperative pruritus. TRIAL REGISTRATION: The trial was registered with the Chinese Clinical Trial Registry (Registration number: ChiCTR2000033520, date: 03/06/2020).

Pilot study of tolerability and safety of opioid receptor antagonists as novel therapies for chronic pain among persons living with HIV with past year heavy drinking: a randomized controlled trial.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03278886.

Clinical features of patients with chronic liver disease in Japan related to alcohol use: Nationwide examination using alcohol use disorders identification test.

AIM: Patients often do not respond truthfully to physicians' interviews concerning alcohol. Few reports regarding the level of alcohol dependence in patients with chronic liver disease (CLD) have been presented. This study aimed to elucidate severity distribution in patients with CLD using the alcohol use disorders identification test (AUDIT). METHODS: From March to June 2022, 2034 Japanese outpatients with CLD, including 415 cases associated with hepatitis C virus, 436 with hepatitis B virus, 173 with alcohol-related liver disease (ARLD), and 1010 with other factors, were interviewed using AUDIT. Clinical features related to alcohol use in these patients were then retrospectively evaluated. RESULTS: In all patients, an AUDIT score 8-14 (harmful use) was noted in 5.8% of hepatitis C virus, 8.9% of hepatitis B virus, 24.3% of ARLD, and 4.4% of other groups, respectively (P < 0.001), while a score ≥15 (dependency) was noted in 3.4%, 3.0%, 27.7%, and 1.9%, respectively (P < 0.001). When the country was divided into regions, the percentages remained similar. Comparisons between patients with and without an AUDIT score ≥8 (n = 1412), performed after exclusion of those without related data (n = 622), showed no significant differences for hepatic reserve function, while those with harmful alcohol use were significantly younger (66 vs. 70 years, P = 0.006) and had a larger percentage of men (80.4% vs. 45.1%, P < 0.001). CONCLUSION: Harmful alcohol and alcohol dependency were observed in approximately 10% of patients with viral or non-viral CLD, after excluding patients with ARLD. Assessment of alcohol intake by use of the AUDIT questionnaire as well as adequate intervention should be considered necessary.

Effect of Different Absorption Enhancers on the Nasal Absorption of Nalmefene Hydrochloride.

The purpose of this work is to explore the effects of novel absorption enhancers on the nasal absorption of nalmefene hydrochloride (NMF). First, the influence of absorption enhancers with different concentrations and types and drug concentrations on the nasal absorption of NMF was investigated in vivo in rats. The absorption enhancers studied include n-dodecyl-ß-D-maltoside (DDM), hydroxypropyl-ß-cyclodextrin (HP-ß-CD), and polyethylene glycol (15)-hydroxy Stearate (Solutol®HS15). At the same time, the in situ toad palate model and rat nasal mucosa model were used to assess the cilia toxicity. The results showed that all the absorption enhancers investigated significantly promote the nasal absorption of NMF, but with different degrees and trends. Among them, the 0.5% (w/v) DDM had the strongest enhancement effect, followed by 0.5% (w/v) Solutol®HS15, 0.25% (w/v) DDM, 0.25% (w/v) Solutol®HS15, 0.1% (w/v) Solutol®HS15, 0.1% (w/v) DDM, and 0.25% (w/v) HP-ß-CD, with absolute bioavailability of 76.49%, 72.14%, 71.00%, 69.46%, 60.41%, 59.42%, and 55.18%, respectively. All absorption enhancers exhibited good safety profiles in nasal ciliary toxicity tests. From the perspective of enhancing effect and safety, we considered DDM to be a promising nasal absorption enhancer. And in addition to DDM, Solutol®HS15 can also promote intranasal absorption of NMF, which will provide another option for the development of nalmefene hydrochloride nasal spray.

Neuroendocrine effects of naltrexone versus nalmefene in humans.

OBJECTIVE: Naltrexone and nalmefene are approved for the treatment of alcohol use disorders, in different countries. Naltrexone is also approved for the treatment for opioid use disorders, most recently in a depot formulation. These compounds target primarily µ(mu)- and κ(kappa)-opioid receptor systems, which are involved in the downstream neurobiological effects of alcohol and in the modulation of neuroendocrine stress systems. The study objective was to compare the neuroendocrine effects of naltrexone and nalmefene on adrenocorticotropic hormone (ACTH), cortisol, and prolactin, in normal volunteers. METHOD: Adult normal volunteers (n = 11 male and n = 9 female) were studied in a stress-minimized inpatient setting on three consecutive days, after intravenous saline, naltrexone HCl (10 mg), or nalmefene HCl (10 mg), in fixed order. ACTH, cortisol, and prolactin were analyzed pre-injection and up to 180 min post-injection. RESULTS: Naltrexone and nalmefene caused elevations in ACTH and cortisol compared with saline. Nalmefene had a greater effect on ACTH and cortisol, compared with naltrexone. Both compounds also caused elevations in prolactin in males (females were not examined, due to the influence of menstrual cycle on prolactin). CONCLUSIONS: This study suggests that both nalmefene and naltrexone have effects potentially due to κ-partial agonism in humans, as well as antagonist effects at µ-receptors.

[Treatment of borderline personality disorder with opioid antagonists: buprenorphine, nalmefene, naloxone and naltrexone in the treatment of dissociative symptoms, self-mutilation and suicidal behavior]. / Tratamiento del Trastorno límite de la personalidad con antagonistas opioides: buprenorfina, nalmefeno, naloxona y naltrexona en el tratamiento de síntomas disociativos, automutilaciones y conducta suicida.

OBJECTIVE: Recent theory has proposed that a dysfunction of the opioid system modulates mood, reward and pain; seems to be unstable in people with Borderline Personality Disorder. Our purpose is to analyze the evidence on the efficacy of the use of buprenorphine, nalmefene, naloxone and naltrexone, in the treatment of dissociative symptoms, self-mutilation and suicidal behavior of these patients. METHOD: We conducted a systematic search of MEDLINE and LILACS databases, to retrieve relevant articles. Included studies were experimental and observational designs of borderline personality samples in which dissociative symptoms, self mutilation or suicidal behavior was reported as an outcome and evaluated with some impact measures. RESULTS: A total of eight studies were reviewed. These provided interesting expectations about posible treatment lines in Borderline Personality Disorder using opioid antagonists. The subgroup most benefited was the one who has analgesia and highest number of diagnostic criteria. CONCLUSIONS: Studies of higher methodological quality are needed, in larger population samples and using control of confounding variables that allow us to estimate a value power calculation, and thus be able to support firm conclusions.

Vibration of effects from diverse inclusion/exclusion criteria and analytical choices: 9216 different ways to perform an indirect comparison meta-analysis.

BACKGROUND: Different methodological choices such as inclusion/exclusion criteria and analytical models can yield different results and inferences when meta-analyses are performed. We explored the range of such differences, using several methodological choices for indirect comparison meta-analyses to compare nalmefene and naltrexone in the reduction of alcohol consumption as a case study. METHODS: All double-blind randomized controlled trials (RCTs) comparing nalmefene to naltrexone or one of these compounds to a placebo in the treatment of alcohol dependence or alcohol use disorders were considered. Two reviewers searched for published and unpublished studies in MEDLINE (August 2017), the Cochrane Library, Embase, and ClinicalTrials.gov and contacted pharmaceutical companies, the European Medicines Agency, and the Food and Drug Administration. The indirect comparison meta-analyses were performed according to different inclusion/exclusion criteria (based on medical condition, abstinence of patients before inclusion, gender, somatic and psychiatric comorbidity, psychological support, treatment administered and dose, treatment duration, outcome reported, publication status, and risk of bias) and different analytical models (fixed and random effects). The primary outcome was the vibration of effects (VoE), i.e. the range of different results of the indirect comparison between nalmefene and naltrexone. The presence of a "Janus effect" was investigated, i.e. whether the 1st and 99th percentiles in the distribution of effect sizes were in opposite directions. RESULTS: Nine nalmefene and 51 naltrexone RCTs were included. No study provided a direct comparison between the drugs. We performed 9216 meta-analyses for the indirect comparison with a median of 16 RCTs (interquartile range = 12-21) included in each meta-analysis. The standardized effect size was negative at the 1st percentile (- 0.29, favouring nalmefene) and positive at the 99th percentile (0.29, favouring naltrexone). A total of 7.1% (425/5961) of the meta-analyses with a negative effect size and 18.9% (616/3255) of those with a positive effect size were statistically significant (p < 0.05). CONCLUSIONS: The choice of inclusion/exclusion criteria and analytical models for meta-analysis can result in entirely opposite results. VoE evaluations could be performed when overlapping meta-analyses on the same topic yield contradictory result. TRIAL REGISTRATION: This study was registered on October 19, 2016, in the Open Science Framework (OSF, protocol available at https://osf.io/7bq4y/ ).

Psychotic Decompensation During Nalmefene Treatment in a Patient With Schizoaffective Disorder: A Case Report.

Objective: Nalmefene is a kappa-opioid receptor agonist/antagonist which is currently prescribed to reduce heavy drinking days. Adverse events (AEs) have previously been described in trials, but these trials excluded patients with psychiatric comorbidities. This is important as psychiatric disorders are frequently associated with alcohol use disorders; therefore, the specific AEs in this population should be investigated. Methods: Here, we describe the case of a patient with diagnosed alcohol use disorder and schizoaffective disorder who received treatment with nalmefene. Results: The patient showed decompensation of psychotic symptoms after two doses of medication, consisting of auditory hallucinations, delusions, and ideas of persecution. The symptoms improved two days after treatment discontinuation. Conclusions: This case indicates that the AEs of nalmefene should be specifically investigated in patients with psychiatric disorders.

Antidepressant-like effects of 3-carboxamido seco-nalmefene (3CS-nalmefene), a novel opioid receptor modulator, in a rat IFN-α-induced depression model.

Patients receiving the cytokine immunotherapy, interferon-alpha (IFN-α) frequently present with neuropsychiatric consequences and cognitive impairments. Patients (25-80%) report symptoms of depression, including, anhedonia, irritability, fatigue and impaired motivation. Our lab has previously demonstrated treatment (170,000IU/kg sc, 3 times per week for 4weeks) of the pro-inflammatory cytokine, IFN-α, induced a depressive phenotype in rats in the forced swim test (FST). Here, we examine the biological mechanisms underlying behavioral changes induced by IFN-α, which may be reflective of mechanisms underlying inflammation associated depression. We also investigate the potential of 3-carboxamido seco-nalmefene (3CS-nalmefene), a novel opioid modulator (antagonist at mu and partial agonist at kappa and delta opioid receptors in vitro), to reverse IFN-α induced changes. In vitro radioligand receptor binding assays and the [35S] GTPγS were performed to determine the affinity of 3CS-nalmefene for the mu, kappa and delta opioid receptors. IFN-α treatment increased circulating and central markers of inflammation and hypothalamic-pituitaryadrenal (HPA) axis activity (IL-6, IL-1ß and corticosterone) while increasing immobility in the FST, impairing of object displacement learning in the object exploration task (OET), and decreasing neuronal proliferation and brain-derived neurotrophic factor (BDNF) in the hippocampus. Treatment with 3CS-nalmefene (0.3mg/kg/sc twice per day, 3 times per week for 4weeks) prevented IFN-α-induced immobility in the FST and impaired object displacement learning. In addition, 3CS-nalmefene prevented IFN-α-induced increases in inflammation and hyperactivity of the HPA-axis, the IFN-α-induced reduction in both neuronal proliferation and BDNF expression in the hippocampus. Overall, these preclinical data would support the hypothesis that opioid receptor modulation is a relevant target for treatment of depression.

Blocking of opioid receptors in experimental formaline-inactivated respiratory syncytial virus (FI-RSV) immunopathogenesis: from beneficial to harmful impacts.

Opioid system plays a significant role in pathophysiological processes, such as immune response and impacts on disease severity. Here, we investigated the effect of opioid system on the immunopathogenesis of respiratory syncytial virus (RSV) vaccine (FI-RSV)-mediated illness in a widely used mouse model. Female Balb/c mice were immunized at days 0 and 21 with FI-RSV (2 × 106 pfu, i.m.) and challenged with RSV-A2 (3 × 106 pfu, i.n.) at day 42. Nalmefene as a universal opioid receptors blocker administered at a dose of 1 mg/kg in combination with FI-RSV (FI-RSV + NL), and daily after live virus challenge (RSV + NL). Mice were sacrificed at day 5 after challenge and bronchoalveolar lavage (BAL) fluid and lungs were harvested to measure airway immune cells influx, T lymphocyte subtypes, cytokines/chemokines secretion, lung histopathology, and viral load. Administration of nalmefene in combination with FI-RSV (FI-RSV + NL-RSV) resulted in the reduction of the immune cells infiltration to the BAL fluid, the ratio of CD4/CD8 T lymphocyte, the level of IL-5, IL-10, MIP-1α, lung pathology, and restored weight loss after RSV infection. Blocking of opioid receptors during RSV infection in vaccinated mice (FI-RSV-RSV + NL) had no significant effects on RSV immunopathogenesis. Moreover, administration of nalmefene in combination with FI-RSV and blocking opioid receptors during RSV infection (FI-RSV + NL-RSV + NL) resulted in an increased influx of the immune cells to the BAL fluid, increases the level of IFN-γ, lung pathology, and weight loss in compared to control condition. Although nalmefene administration within FI-RSV vaccine decreases vaccine-enhanced infection during subsequent exposure to the virus, opioid receptor blocking during RSV infection aggravates the host inflammatory response to RSV infection. Thus, caution is required due to beneficial/harmful functions of opioid systems while targeting as potentially therapies.

Severe central sleep apnoea associated with nalmefene: a case report.

Nalmefene, an opioid antagonist, has recently been approved for the treatment of alcohol dependence. We describe here the first case of a 52-year-old woman who developed a severe central sleep apnoea (CSA) 5 months after initiation of nalmefene. Scoring of ventilation during sleep recording revealed an apnoea-hypopnoea index of 67/h with 98.7% of central events and an apnoea index of 65/h. Nalmefene was withdrawn and a new polysomnography was performed which concluded that CSA has disappeared. Pathophysiology is still unclear but could involve the κ-opioid receptors. Physicians should be aware that CSA might affect patients treated with nalmefene. Further investigations are required to determine the pathophysiology, frequency, and treatment of CSA associated with nalmefene and other therapy for alcohol disorders.

Efficacy and safety of sodium oxybate in alcohol-dependent patients with a very high drinking risk level.

Medication development for alcohol relapse prevention or reduction of consumption is highly challenging due to methodological issues of pharmacotherapy trials. Existing approved medications are only modestly effective with many patients failing to benefit from these therapies. Therefore, there is a pressing need for other effective treatments with a different mechanism of action, especially for patients with very high (VH) drinking risk levels (DRL) because this is the most severely affected population of alcohol use disorder patients. Life expectancy of alcohol-dependent patients with a VH DRL is reduced by 22 years compared with the general population and approximately 90 000 alcohol-dependent subjects with a VH DRL die prematurely each year in the EU (Rehm et al. ). A promising new medication for this population is sodium oxybate, a compound that acts on GABAB receptors and extrasynaptic GABAA receptors resulting in alcohol-mimetic effects. In this article, a European expert group of alcohol researchers and clinicians summarizes data (a) from published trials, (b) from two new-as yet unpublished-large clinical trials (GATE 2 (n = 314) and SMO032 (n = 496), (c) from post hoc subgroup analyses of patients with different WHO-defined DRLs and (d) from multiple meta-analyses. These data provide convergent evidence that sodium oxybate is effective especially in a subgroup of alcohol-dependent patients with VH DRLs. Depending on the study, abstinence rates are increased up to 34 percent compared with placebo with risk ratios up to 6.8 in favor of sodium oxybate treatment. These convergent data are supported by the clinical use of sodium oxybate in Austria and Italy for more than 25 years. Sodium oxybate is the sodium salt of γ-hydroxybutyric acid that is also used as a recreational (street) drug suggestive of abuse potential. However, a pharmacovigilance database of more than 260 000 alcohol-dependent patients treated with sodium oxybate reported very few adverse side effects and only few cases of abuse. We therefore conclude that sodium oxybate is an effective, well-tolerated and safe treatment for withdrawal and relapse prevention treatment, especially in alcohol-dependent patients with VH DRL.

Nalmefene, Given as Needed, in the Routine Treatment of Patients with Alcohol Dependence: An Interventional, Open-Label Study in Primary Care.

AIMS: This 12-week, open-label, primary care study (NCT02195817) evaluated the efficacy and safety of nalmefene, taken as needed, to reduce alcohol consumption in adults with a diagnosis of alcohol dependence and drinking at least at high drinking risk levels (DRL, > 60 g/day for men, > 40 g/day for women). METHODS: Following the Screening Visit, patients recorded their daily alcohol consumption for 2 weeks. Patients were then categorised by their self-reported drinking levels; those who maintained at least a high DRL in the 2-week period were included in Cohort-A, and those who reduced their alcohol consumption below high DRL were included in Cohort-B. Cohort-A received simple psychosocial interventions and were supplied with nalmefene 18 mg to be taken on days when they perceived a risk of drinking alcohol. Patients in Cohort-B received a simple psychosocial intervention and were treated per normal practice. RESULTS: Of the 378 enrolled patients, 330 were included in Cohort-A and 48 in Cohort-B. For patients in Cohort-A, the mean change from screening to Week-12 in the number of heavy drinking days/month was -13.1 days/month (95% CI -14.4 to -11.9, p < 0.0001). Overall, 55% of patients reduced their DRL by ≥2 risk levels and 44% of patients reduced to a low DRL. The most common adverse events were nausea (18.3%) and dizziness (17.7%). Patients in Cohort-B maintained their lower level alcohol consumption at the 12-week follow-up. CONCLUSIONS: Patients with alcohol dependence treated in primary care with nalmefene, taken as needed, in conjunction with simple psychosocial support, significantly reduced their alcohol consumption. Treatment was well tolerated.

Nalmefene attenuates malignant potential in colorectal cancer cell via inhibition of opioid receptor.

Morphine is postulated a risk factor in promoting tumor growth and metastasis during the preoperative period, and high glycolysis of tumor cells is proved to accelerate tumor progression. In this study, we investigated whether nalmefene, an opioid receptor inhibitor, could inhibit CT26 colon cancer cell growth through influencing cell glycolysis. CCK8 and transwell migration assays showed that nalmefene inhibited CT26 cells viability and migration in a concentration-dependent manner. Extracellular acidification rate and oxygen consumption rate showed that nalmefene inhibited glycolysis of CT26 cells. Moreover, western blot analysis and quantitative real-time PCR revealed that nalmefene decreased the expressions of enzymes related to glycolysis. Flow cytometry results revealed that intracellular calcium (Ca2+) level was changed by nalmefene, western blot analysis showed that nalmefene decreased calmodulin expression and calcium/calmodulin dependent protein kinases II (CaMK II) phosphorylation, thus inhibiting the serine/threonine kinase (AKT)-glycogen synthase kinase-3ß (GSK-3ß) pathway. Furthermore, the effects of KN93, an inhibitor of CaMK II, were similar to the effects of nalmefene, and the anti-tumor effect of nalmefene could be counteracted by morphine. In conclusion, the anti-tumor effect of nalmefene may be achieved by inhibiting opioid receptor and down-regulating calmodulin expression and CaMK II phosphorylation, thus inhibiting AKT-GSK-3ß pathway and the glycolysis of CT26 cells.

Nalmefene Prevents Alcohol-Induced Neuroinflammation and Alcohol Drinking Preference in Adolescent Female Mice: Role of TLR4.

BACKGROUND: We previously showed that, by activating innate immune receptors Toll-like 4 (TLR4), adolescent intermittent ethanol (EtOH) exposure causes neuroinflammation, myelin damage, and behavioral dysfunctions. Recent findings reveal that clinically used opioid antagonists naltrexone (NT) and naloxone (NX) inhibit opioid-induced TLR4 signaling and that NT, NX, and nalmefene (NF), the 6-methylene derivative of NX, are able to reduce alcohol drinking escalation. METHODS: NF (0.1 mg/kg, intraperitoneally) was injected 1 hour prior to EtOH (3 g/kg, intraperitoneally) following intermittent treatment in female (PND35) adolescent mice. Inflammatory molecules, myelin proteins, and apoptotic markers were assessed in the prefrontal cortex (PFC) and striatum/nucleus accumbens (STR/NAcc). The effect of NF on alcohol drinking preference was evaluated in both the wild-type and TLR4 knockout (KO) adolescent mice. Using astroglial cells, the inhibitory potential of NT, NX, and NF on lipopolysaccharide (LPS), or the EtOH-triggered TLR4 response, was compared. RESULTS: Our findings indicate that NF prevents the up-regulation of cytokines (IL-1ß, IL-17A, TNF-α), chemokines (MCP-1, MIP-1, KC), and pro-inflammatory mediators (iNOS, COX-2), along with myelin damage and apoptotic events, in both PFC and STR/NAcc. NF also abolishes EtOH-induced escalation of alcohol preference/consumption, but has no effect when administered to TLR4-KO mice. In vitro experiments indicate that NX and NF inhibit TLR4 activation upon LPS or EtOH stimulation. Immunofluorescence studies and lipid rafts isolation show that NF is able to prevent TLR4 translocation to lipid rafts/caveolae in astrocytes. CONCLUSIONS: These results suggest that NF prevents neuroinflammation and brain damage by blocking the TLR4 response and also support the role of central pro-inflammatory immune signaling in the modulation of alcohol consumption/addiction.

Population pharmacokinetics of nalmefene in healthy subjects and its relation to µ-opioid receptor occupancy.

AIMS: The aims of this study were to develop a population pharmacokinetic (PK) model to describe the PK of nalmefene in healthy subjects and to relate the exposure of nalmefene to the µ-opioid receptor occupancy by simulations in the target population. METHODS: Data from nine phase I studies (243 subjects) with extensive blood sampling were pooled and used for the population PK model building. Data from four other phase I studies (85 subjects) were pooled and used as an external validation dataset. Eight subjects from an imaging study contributed occupancy data and the pharmacokinetic/pharmacodynamic (PK/PD) relationship was modelled. Combining the population PK model and the PK/PD relationship enabled simulations to predict µ-opioid occupancy. RESULTS: A two compartment model with first order absorption best described the nalmefene PK data. The typical subject in the population was estimated to have a systemic clearance of 60.4 l h(-1) and a central volume of distribution of 266 l. Absolute oral bioavailability was estimated to 41% without food intake and with food about 53%. Simulation of the µ-opioid receptor occupancy shows that the 95% confidence bound is within or above 60-90% occupancy for up to 22-24 h after a single dose of 20 mg nalmefene. CONCLUSIONS: A robust population PK model for nalmefene was developed. Based on the concentration-occupancy model the µ-opioid receptor occupancy after a single 20 mg dose of nalmefene is predicted to be above the target therapeutic occupancy for about 24 h in about 95% of the target population.

Clinical experience about an unexpected adverse event during nalmefene treatment in two patients with alcohol use disorder.

WHAT IS KNOWN AND OBJECTIVE: Nalmefene, a new opioid system regulator, has recently been approved for the treatment of alcohol dependence, primarily for reducing heavy drinking days. CASES DESCRIPTION: Two patients with a diagnosis of alcohol use disorder were treated with nalmefene. Both patients developed fatigue and deep sleepiness after 2 days of treatment. Only after 1 day of drug discontinuation, symptoms normalized. WHAT IS NEW AND CONCLUSION: We have analysed symptoms' development before and after treatment discontinuation and the possible association with nalmefene therapy. This case should pinpoint our attention on this adverse event for a careful choice of anticraving therapy in patients with severe alcohol use disorder.