Cannabidiol Reduces Nicotine Withdrawal Severity and State Anxiety During an Acute E-cigarette Abstinence Period: A Novel, Open-Label Study

Introduction: Despite efforts to curb nicotine use, 8.1 million adults in the United States use e-cigarettes. Notably, the majority of nicotine-containing e-cigarette users report wanting to quit in the near future, yet there is a dearth of research surrounding intervention efforts. Cannabidiol (CBD) has potential to facilitate e-cigarette quit attempts by decreasing withdrawal symptom intensity and anxiety during nicotine e-cigarette abstinence. Methods: This study employed an open-label, crossover design (n=20) to test the hypothesis that among daily nicotine-containing e-cigarette users, oral administration of 320 mg CBD would reduce self-reported nicotine withdrawal severity and state anxiety following a 4-h e-cigarette abstinence period compared to withdrawal and anxiety reported after abstinence in the absence of CBD. Results: After controlling for participants' positive CBD expectancies, results were consistent with hypotheses, suggesting CBD reduced both nicotine withdrawal symptom severity and state anxiety during e-cigarette abstinence. Conclusion: These preliminary findings suggest testing the impact of CBD on e-cigarette cessation attempts is warranted.

A novel tramadol-polycaprolactone implant could palliate heroin conditioned place preference and withdrawal in rats: behavioral and neurochemical study

Drug dependence is a chronic brain disease characterized by craving and recurrent episodes of relapse. Tramadol HCl is a promising agent for withdrawal symptoms management, considering its relatively low abuse potential and safety. Oral administration, however, is not preferred in abstinence maintenance programs. Introducing an implantable, long-lasting formula is suggested to help outpatient abstinence programs achieve higher rates of treatment continuation. Tramadol implants (T350 and T650) were prepared on polycaprolactone polymer ribbons by the wet method. Male Wistar rats were adapted to heroin-conditioned place preference (CPP) at escalating doses (3-30 mg/kg, intraperitoneally, for 14 days). Implants were surgically implanted in the back skin of rats. After 14 days, the CPP score was recorded. Naloxone (1 mg/kg, intraperitoneally) was used to induce withdrawal on day 15, and symptoms were scored. Elevated plus maze and open field tests were performed for anxiety-related symptoms. Striata were analyzed for neurochemical changes reflected in dopamine, 3,4-dihydroxyphenyl acetic acid, gamma-aminobutyric acid, and serotonin levels. Brain oxidative changes including glutathione and lipid peroxides were assessed. The tramadol implants (T350 and T650) reduced heroin CPP and limited naloxone-induced withdrawal symptoms. The striata showed increased levels of 3,4-dihydroxyphenyl acetic acid, and serotonin and decreased levels of gamma-aminobutyric acid and dopamine after heroin withdrawal induction, which were reversed after implanting T350 and T650. Implants restore the brain oxidative state. Nonsignificant low naloxone-induced withdrawal score after the implant was used in naive subjects indicating low abuse potential of the implants. The presented tramadol implants were effective at diminishing heroin CPP and withdrawal in rats, suggesting further investigations for application in the management of opioid withdrawal.

Teneurin C-terminal associated peptide (TCAP)-1 attenuates the development and expression of naloxone-precipitated morphine withdrawal in male Swiss Webster mice

RATIONALE

Corticotropin-releasing factor (CRF), the apical stress-inducing hormone, exacerbates stress and addictive behaviors. TCAP-1 is a peptide that directly inhibits both CRF-mediated stress and addiction-related behaviors; however, the direct action of TCAP-1 on morphine withdrawal-associated behaviors has not previously been examined.

OBJECTIVE

To determine whether TCAP-1 administration attenuates behavioral and physiological consequences of morphine withdrawal in mice.

METHODS

Mice were administered via subcutaneous route TCAP-1 either before or after initial morphine exposure, after which jumping behavior was quantified to assess the effects of TCAP-1 on naloxone-precipitated morphine withdrawal. As a comparison, mice were treated with nonpeptide CRF1 receptor antagonist CP-154,526. In one experiment, plasma corticosterone (CORT) was also measured as a physiological stress indicator.

RESULTS

Pretreatment with TCAP-1 (10-250 nmol/kg) before morphine treatment significantly inhibited the development of naloxone-precipitated withdrawal. TCAP-1 (250-500 nmol/kg) treatment administered after morphine treatment attenuated the behavioral expression of naloxone-precipitated withdrawal. TCAP-1 (250 nmol/kg) treatment during morphine treatment was more effective than the optimal dosing of CP-154,526 (20 mg/kg) at suppressing the behavioral expression of naloxone-precipitated withdrawal, despite similar reduction of withdrawal-induced plasma CORT level increases.

CONCLUSIONS

These findings establish TCAP-1 as a potential therapeutic candidate for the prevention and treatment of morphine withdrawal.

Initiation of Buprenorphine Treatment of Opioid Use Disorder in Pediatric Emergency Departments

Pediatric emergency departments (EDs) in the United States are facing a rise in the number of children and adolescents who present with opioid use disorder (OUD), often driven by illicitly manufactured fentanyl. Medication treatment of pediatric OUD in the ED setting is often limited to symptomatic treatment of opioid withdrawal. Pediatric patients are rarely offered medications for OUD, especially in the ED setting. Buprenorphine is a partial opioid agonist that is Food and Drug Administration-approved for the treatment of OUD in patients aged 16 years and older. Adult studies have demonstrated that ED initiation of medication for OUD such as buprenorphine is feasible, safely treats withdrawal symptoms, and can improve patient compliance with outpatient follow-up. However, initiation of buprenorphine in the ED has not been well-studied in the pediatric population. We present 2 cases of adolescent patients, a 16-year-old male and 17-year-old female, who presented to the ED with opioid withdrawal. They were both diagnosed with severe OUD because of their use of counterfeit pills containing fentanyl. Both patients were successfully started on buprenorphine/naloxone in the pediatric ED before transitioning to an outpatient addiction clinic for continued treatment. The case series demonstrates the feasibility of ED-based buprenorphine initiation for adolescents, an important and timely intervention for adolescents with OUD.

Pannexin-1 channel inhibition alleviates opioid withdrawal in rodents by modulating locus coeruleus to spinal cord circuitry

Opioid withdrawal is a liability of chronic opioid use and misuse, impacting people who use prescription or illicit opioids. Hyperactive autonomic output underlies many of the aversive withdrawal symptoms that make it difficult to discontinue chronic opioid use. The locus coeruleus (LC) is an important autonomic centre within the brain with a poorly defined role in opioid withdrawal. We show here that pannexin-1 (Panx1) channels expressed on microglia critically modulate LC activity during opioid withdrawal. Within the LC, we found that spinally projecting tyrosine hydroxylase (TH)-positive neurons (LCspinal) are hyperexcitable during morphine withdrawal, elevating cerebrospinal fluid (CSF) levels of norepinephrine. Pharmacological and chemogenetic silencing of LCspinal neurons or genetic ablation of Panx1 in microglia blunted CSF NE release, reduced LC neuron hyperexcitability, and concomitantly decreased opioid withdrawal behaviours in mice. Using probenecid as an initial lead compound, we designed a compound (EG-2184) with greater potency in blocking Panx1. Treatment with EG-2184 significantly reduced both the physical signs and conditioned place aversion caused by opioid withdrawal in mice, as well as suppressed cue-induced reinstatement of opioid seeking in rats. Together, these findings demonstrate that microglial Panx1 channels modulate LC noradrenergic circuitry during opioid withdrawal and reinstatement. Blocking Panx1 to dampen LC hyperexcitability may therefore provide a therapeutic strategy for alleviating the physical and aversive components of opioid withdrawal.

Oral ethanol prescribing for alcohol withdrawal syndrome: initial findings and future directions following implementation within a United Kingdom National Health Service setting

INTRODUCTION

Prescribing of ethanol may be an alternative to benzodiazepines for managing alcohol withdrawal syndrome. We present our experience of oral ethanol prescribing within an acute United Kingdom National Health Service setting.

METHODS

A retrospective review of patients presenting with alcohol withdrawal who were managed with oral ethanol or benzodiazepines was performed from data collected across two acute care settings. Ethanol prescribing inclusion: high risk of delirium tremens, or a history of harmful alcohol consumption (typically ≥30 units/day; in which 1 unit = 8 grams of alcohol; one standard United States drink = 14 grams of alcohol) or known to have a history of severe alcohol withdrawal, alcohol-related seizures or delirium tremens. Inverse propensity score weighting was used to partially account for variance between the two patient populations.

RESULTS

Fifty (82 per cent male; average age 50.9 years) and 93 (84 per cent male; average age 46.5 years) patients in receipt of benzodiazepines or ethanol, respectively, were included. The likelihood of hospital admission was significantly reduced when individuals were managed with ethanol (odds ratio 0.206 (95 per cent confidence interval; 0.066-0.641), Wald chi-square P = 0.006). In those not admitted, the treatment type had no significant impact on length of stay or the number of occasions a pharmacological agent was required. In those admitted, treatment had no significant effect on length of stay.

DISCUSSION

We offer preliminary evidence to support a role of oral ethanol in the management of patients with alcohol withdrawal. We have implemented a robust and translatable guideline. Despite limitations in the data set the impact of ethanol in reducing the likelihood of admission remained significant.

CONCLUSIONS

In individuals at significant risk of severe alcohol withdrawal, prescribing ethanol as part of a comprehensive care plan, may reduce unplanned admissions. The preliminary findings presented here warrant further assessment through prospective studies.

Mitragynine (Kratom)-Withdrawal behaviour and cognitive impairments can be ameliorated by an epigenetic mechanism

BACKGROUND AND PURPOSE

Kratom is a preparation from Mitragyna speciosa, which is used as a natural drug preparation for many purposes around the world. However, an overdose of Kratom may cause addiction-like problems including aversive withdrawal states resulting in cognitive impairments via unknown mechanisms. Its main psychoactive alkaloid is mitragynine, showing opioid-like properties.

EXPERIMENTAL APPROACH

Here, we analysed the neuropharmacological effects of mitragynine compared with morphine withdrawal in rats and searched for a pharmacological treatment option that may reverse the occurring cognitive deficits that usually aggravate withdrawal.

KEY RESULTS

We found that withdrawal from 14-day mitragynine (1-10 mg·kg-1·day-1) treatment caused dose-dependent behavioural withdrawal signs resembling those of morphine (5 mg·kg-1·day-1) withdrawal. However, mitragynine (5 and 10 mg·kg-1·day-1) withdrawal also induced impairments in a passive avoidance task. Mitragynine withdrawal not only reduced hippocampal field excitatory postsynaptic potential (fEPSP) amplitudes in basal synaptic transmission and long-term potentiation (LTP) but also reduced epigenetic markers, such as histone H3K9 and H4K12 expression. At the same time, it up-regulates HDAC2 expression. Targeting the epigenetic adaptations with the HDAC inhibitor, SAHA, reversed the effects of mitragynine withdrawal on epigenetic dysregulation, hippocampal input/output curves, paired-pulse facilitation, LTP and attenuated the cognitive deficit. However, SAHA amplified the effects of morphine withdrawal.

CONCLUSION AND IMPLICATIONS

The data from this work show that changes in histone expression and downstream hippocampal plasticity may explain mitragynine, but not morphine, withdrawal behaviours and cognitive impairments. Thus, it may provide a new treatment approach for aversive Kratom/mitragynine withdrawal and addiction.

Barriers and facilitators to use of buprenorphine in state-licensed specialty substance use treatment programs: A survey of program leadership

INTRODUCTION

Medications for opioid use disorder (MOUD), including buprenorphine, reduce overdose risk and improve outcomes for individuals with opioid use disorder (OUD). However, historically, most non-opioid treatment program (non-OTP) specialty substance use treatment programs have not offered buprenorphine. Understanding barriers to offering buprenorphine in specialty substance use treatment settings is critical for expanding access to buprenorphine. This study aims to examine program-level attitudinal, financial, and regulatory factors that influence clients' access to buprenorphine in state-licensed non-OTP specialty substance use treatment programs.

METHODS

We surveyed leadership from state-licensed non-OTP specialty substance use treatment programs in New Jersey about organizational characteristics, including medications provided on- and off-site and percentage of OUD clients receiving any type of MOUD, and perceived attitudinal, financial, and regulatory barriers and facilitators to buprenorphine. The study estimated prevalence of barriers and compared high MOUD reach (n = 36, 35 %) and low MOUD reach (n = 66, 65 %) programs.

RESULTS

Most responding organizations offered at least one type of MOUD either on- or off-site (n = 80, 78 %). However, 71 % of organizations stated that fewer than a quarter of their clients with OUD use any type of MOUD. Endorsement of attitudinal, financial, and institutional barriers to buprenorphine were similar among high and low MOUD reach programs. The most frequently endorsed government actions suggested to increase use of buprenorphine were facilitating access to long-acting buprenorphine (n = 95, 96 %), education and stigma reduction for clients and families (n = 95, 95 %), and financial assistance to clients to pay for medications (n = 90, 90 %).

CONCLUSIONS

Although non-OTP specialty substance use programs often offer clients access to MOUD, including buprenorphine, most OUD clients do not actually receive MOUD. Buprenorphine uptake in these settings may require increased financial support for programs and clients, more robust education and training for providers, and efforts to reduce the stigma associated with medication among clients and their families.

Targeting GLP-1 receptors to reduce nicotine use disorder: Preclinical and clinical evidence

Nicotine use disorder (NUD) remains a leading cause of preventable death in the U.S. Unfortunately, current FDA-approved pharmacotherapies for smoking cessation have limited efficacy and are associated with high rates of relapse. One major barrier to long-term smoking abstinence is body weight gain during withdrawal. Nicotine withdrawal-induced body weight gain can also lead to development of chronic disease states like obesity and type II diabetes mellitus. Therefore, it is critical to identify novel pharmacotherapies for NUD that decrease relapse and nicotine withdrawal symptoms including body weight gain. Recent studies demonstrate that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate voluntary nicotine taking and seeking and prevent withdrawal-induced hyperphagia and body weight gain. Emerging evidence also suggests that GLP-1R agonists improve cognitive deficits, as well as depressive- and anxiety-like behaviors, which contribute to smoking relapse during withdrawal. While further studies are necessary to fully characterize the effects of GLP-1R agonists on NUD and understand the mechanisms by which GLP-1R agonists decrease nicotine withdrawal-mediated behaviors, the current literature supports GLP-1R-based approaches to treating NUD.

How Should Risks and Benefits of Short-Acting Opioids Be Evaluated in the Care of Inpatients With OUD?

Severe opioid withdrawal, risk of patient-initiated discharge, and some inpatients' use of unregulated substances prompt clinical and ethical questions considered in this commentary on a case. Short-acting opioids can be used to manage inpatients' pain and opioid use disorder (OUD) withdrawal symptoms. Including evidence-based interventions-such as naloxone kits, substance use equipment, and supervised consumption-in some inpatients' care plans may make those patients safer and reduce their risk of death. These and other strategies align with clinicians' ethical duties to minimize harms and maximize benefits for inpatients with OUD.

Effects of Thymbra spicata extract and Thymol on morphine withdrawal syndrome in mice (insights to the liver function, antioxidant, and behavioral responses)

Safe chemicals for drug withdrawal can be extracted from natural sources. This study investigates the effects of clonidine and Thymbra spicata extract (TSE) on mice suffering from morphine withdrawal syndrome. Thymol, which is the active constituent in TSE, was also tested. A total of 90 mice were divided into nine groups. Group 1 was the control group, while Group 2 was given only morphine, and Group 3 received morphine and 0.2 mg/kg of clonidine. Groups 4-6 were given morphine along with 100, 200, and 300 mg/kg of TSE, respectively. Groups 7-9 received morphine plus 30, 60, and 90 mg/kg of Thymol, respectively, for 7 days. An oral naloxone challenge of 3 mg/kg was used to induce withdrawal syndrome in all groups. Improvement of liver enzyme levels (aspartate aminotransferase, alkaline phosphatase, and alanine transaminase) (p < .01) and behavioral responses (frequencies of jumping, frequencies of two-legged standing, Straub tail reaction) (p < .01) were significantly observed in the groups receiving TSE and Thymol (Groups 4-9) compared to Group 2. Additionally, antioxidant activity in these groups was improved compared to Group 2. Nitric oxide significantly decreased in Groups 4 and 6 compared to Groups 2 and 3 (p < .01). Superoxide dismutase increased dramatically in Groups 5, 8, and 9 compared to Groups 2 and 3 (p < .01). Groups 5-9 were significantly different from Group 2 in terms of malondialdehyde levels (p < .01). Certain doses of TSE and Thymol were found to alleviate the narcotics withdrawal symptoms. This similar effect to clonidine can pave the way for their administration in humans.

Incidence of antidepressant discontinuation symptoms: a systematic review and meta-analysis

BACKGROUND

Antidepressant discontinuation symptoms are becoming an increasingly important part of clinical practice, but the incidence of antidepressant discontinuation symptoms has not been quantified. An estimate of antidepressant discontinuation symptoms incidence could inform patients and clinicians in the discontinuation of treatment, and provide useful information to researchers in antidepressant treatments. We aimed to assess the incidence of antidepressant discontinuation symptoms in patients discontinuing both antidepressants and placebo in the published literature.

METHODS

We systematically searched Medline, EMBASE, and CENTRAL from database inception until Oct 13, 2022 for randomised controlled trials (RCTs), other controlled trials, and observational studies assessing the incidence of antidepressant discontinuation symptoms. To be included, studies must have investigated cessation or tapering of an established antidepressant drug (excluding antipsychotics, lithium, or thyroxine) or placebo in participants with any mental, behavioural, or neurodevelopmental disorder. We excluded studies in neonates, and those using antidepressants for physical conditions such as pain syndromes due to organic disease. After study selection, summary data extraction, and risk of bias evaluation, data were pooled in random-effects meta-analyses. The main outcome was the incidence of antidepressant discontinuation symptoms after discontinuation of antidepressants or placebo. We also analysed the incidence of severe discontinuation symptoms. Sensitivity and meta-regression analyses tested a selection of methodological variables.

FINDINGS

From 6095 articles screened, 79 studies (44 RCTs and 35 observational studies) covering 21 002 patients were selected (72% female, 28% male, mean age 45 years [range 19·6-64·5]). Data on ethnicity were not consistently reported. 16 532 patients discontinued from an antidepressant, and 4470 patients discontinued from placebo. Incidence of at least one antidepressant discontinuation symptom was 0·31 (95% CI 0·27-0·35) in 62 study groups after discontinuation of antidepressants, and 0·17 (0·14-0·21) in 22 study groups after discontinuation of placebo. Between antidepressant and placebo groups of included RCTs, the summary difference in incidence was 0·08 [0·04-0·12]. The incidence of severe antidepressant discontinuation symptoms after discontinuation of an antidepressant was 0·028 (0·014-0·057) compared with 0·006 (0·002-0·013) after discontinuation of placebo. Desvenlafaxine, venlafaxine, imipramine, and escitalopram were associated with higher frequencies of discontinuation symptoms, and imipramine, paroxetine, and either desvenlafaxine or venlafaxine were associated with a higher severity of symptoms. Heterogeneity of results was substantial.

INTERPRETATION

Considering non-specific effects, as evidenced in placebo groups, the incidence of antidepressant discontinuation symptoms is approximately 15%, affecting one in six to seven patients who discontinue their medication. Subgroup analyses and heterogeneity figures point to factors not accounted for by diagnosis, medication, or trial-related characteristics, and might indicate subjective factors on the part of investigators, patients, or both. Residual or re-emerging psychopathology needs to be considered when interpreting the results, but our findings can inform clinicians and patients about the probable extent of antidepressant discontinuation symptoms without causing undue alarm.

FUNDING

None.

Gradually tapering off antipsychotics: lessons for practice from case studies and neurobiological principles

PURPOSE OF REVIEW

There has been an increasing focus on deprescribing in psychiatry recently, particularly of antipsychotic medication, with recognition that not all patients with psychotic disorders require lifelong medication. We summarize some empirical and theoretical papers, and examine case studies to provide instruction on this topic.

RECENT FINDINGS

Recent studies have found that slower tapering (over months or longer) of antipsychotics is associated with a lower relapse rate than quicker tapering (weeks). Case studies presented suggest that the process of reduction is associated with the precipitation or exacerbation of psychotic symptoms and that a slower process of reduction may minimize this effect. This may be because faster reductions cause greater disruption of homeostatic equilibria, provoking psychotic symptoms either as direct withdrawal symptoms or consequences of nonpsychotic withdrawal symptoms (e.g. insomnia) - although not all patients will experience withdrawal symptoms. This suggests that smaller dose reductions, especially at lower doses, made very gradually, may minimize the risk of psychotic symptoms.

SUMMARY

Slower tapering of antipsychotics may provide time for adaptations made to the presence of the medications to resolve, thus reducing the disruption to homeostatic equilibrium caused by dose reduction, potentially reducing the risk of relapse. Exacerbation of psychotic symptoms on antipsychotic reduction may not represent evidence of the need for a higher dose of antipsychotic on a long-term basis but may indicate the need for more gradual reduction. Gradual reduction of antipsychotics, especially after long-term use in clinical practice is prudent.

Buprenorphine for the Treatment of Pain in Cancer Patients

BACKGROUND

Opioids remain the cornerstone for the treatment of moderate to severe cancer pain. Due to benefits over full agonist opioids (FAO), buprenorphine has emerged as an alternative treatment.

PURPOSE/HYPOTHESIS

Buprenorphine is only approved for the treatment of pain that is chronic non-cancer. Cancer-related pain is often progressive with breakthrough pain. There is limited evidence for using short-acting FAO in combination with buprenorphine. There are concerns about withdrawal and the efficacy of pain control using buprenorphine. We hypothesize buprenorphine, in combination with short-acting FAOs, can adequately control cancer- related pain without causing withdrawal symptoms. Procedures/data/observations: Our prospective, single-arm, open-label study enrolls patients with cancer-related pain who are on buprenorphine in combination with an FAO at > 30 mg OME/day, either requiring long-acting pain relief or their pain is not controlled with an FAO alone. Our study is ongoing, with 15 patients enrolled and a target of 50. The patient's pain is self-assessed daily using a mobile application. Withdrawal is assessed regularly using a modified Clinical Opioid Withdrawal Scale (COWS) score.

CONCLUSIONS/APPLICATIONS

Buprenorphine appears to be effective for the treatment of cancer pain without causing withdrawal in combination with short-acting FAO >30 mg/day.

Psychoactive plant derivatives (ayahuasca, ibogaine, kratom) and their application in opioid withdrawal and use disorder - a narrative review

The opioid epidemic and limited access to treatment for opioid withdrawal (OW) and opioid use disorder (OUD) has led individuals to seek alternative treatments. This narrative review aims to educate clinicians on the mechanisms of action, toxicity, and applications of psychoactive plant-based substances patients may be using to self-treat OUD and OW. We specifically discuss ayahuasca, ibogaine, and kratom as they have the most evidence for applications in OUD and OW from the last decade (2012-2022). Evidence suggests these substances may have efficacy in treating OW and OUD through several therapeutic mechanisms including their unique pharmacodynamic effects, rituals performed around ingestion, and increased neuroplasticity. The current evidence for their therapeutic application in OUD and OW is primarily based on small observational studies or animal studies. High-quality, longitudinal studies are needed to clarify safety and efficacy of these substances in treatment of OW and OUD.

Establishing a research agenda for the study and assessment of opioid withdrawal

The opioid crisis is an international public health concern. Treatments for opioid use disorder centre largely on the management of opioid withdrawal, an aversive collection of signs and symptoms that contribute to opioid use disorder. Whereas in the past 50 years more than 90 medications have been developed for depression, only five medications have been developed for opioid use disorder during this period. We posit that underinvestment has occurred in part due to an underdeveloped understanding of opioid withdrawal syndrome. This Personal View summarises substantial gaps in our understanding of opioid withdrawal that are likely to continue to limit major advancements in its treatment. There is no firm consensus in the field as to how withdrawal should be precisely defined; 10-550 symptoms of withdrawal can be measured on 18 scales. The imprecise understanding of withdrawal is likely to result in overestimating or underestimating the severity of an individual's withdrawal syndrome or potential therapeutic effects of different candidate medications. The severity of the opioid crisis is not remitting, and an international research agenda for the study and assessment of opioid withdrawal is necessary to support transformational changes in withdrawal management and treatment of opioid use disorder. Nine actionable targets are delineated here: develop a consensus definition of opioid withdrawal; understand withdrawal symptomatology after exposure to different opioids (particularly fentanyl); understand precipitated opioid withdrawal; understand how co-exposure of other drugs (eg, xylazine and stimulants) influences withdrawal expression; examine individual variation in withdrawal phenotypes; precisely characterise the protracted withdrawal syndrome; identify biomarkers of opioid withdrawal severity; identify predictors of opioid withdrawal severity; and understand which symptoms are most closely associated with treatment attrition or relapse. The US Food and Drug Administration recently established a formal indication for opioid withdrawal that has invigorated interest in drug development for opioid withdrawal management. Action is now needed to support these interests and help industry identify new classes of medications so that real change can be achieved for people with opioid use disorder.

Pharmacologic profile of ITI-333: a novel molecule for treatment of substance use disorders

RATIONALE

Medications are urgently needed to treat symptoms of drug withdrawal and mitigate dysphoria and psychiatric comorbidities that drive opioid abuse and relapse. ITI-333 is a novel molecule in development for treatment of substance use disorders, psychiatric comorbidities, and pain.

OBJECTIVE

Characterize the preclinical profile of ITI-333 using pharmacological, behavioral, and physiological assays.

METHODS

Cell-based assays were used to measure receptor binding and intrinsic efficacy of ITI-333; animal models were employed to assess effects on opioid reinstatement, precipitated oxycodone withdrawal, and drug abuse liability.

RESULTS

In vitro, ITI-333 is a potent 5-HT2A receptor antagonist (Ki = 8 nM) and a biased, partial agonist at μ-opioid (MOP) receptors (Ki = 11 nM; lacking β-arrestin agonism) with lesser antagonist activity at adrenergic α1A (Ki = 28 nM) and dopamine D1 (Ki = 50 nM) receptors. In vivo, ITI-333 blocks 5-HT2A receptor-mediated head twitch and MOP receptor-mediated effects on motor hyperactivity in mice. ITI-333 alone is a naloxone-sensitive analgesic (mice) which suppresses somatic signs of naloxone-precipitated oxycodone withdrawal (mice) and heroin cue-induced reinstatement responding without apparent tolerance or physical dependence after chronic dosing (rats). ITI-333 did not acutely impair gastrointestinal or pulmonary function (rats) and was not intravenously self-administered by heroin-maintained rats or rhesus monkeys.

CONCLUSIONS

ITI-333 acts as a potent 5-HT2A receptor antagonist, as well a biased MOP receptor partial agonist with low intrinsic efficacy. ITI-333 mitigates opioid withdrawal/reinstatement, supporting its potential utility as a treatment for OUD.

Anticholinergic deprescribing: A case report demonstrating improved cognition and function with minimal adverse withdrawal effects

Anticholinergic-induced cognitive impairment may be partially reversible upon cessation. A barrier to deprescribing of anticholinergics is the unknown risk of anticholinergic adverse drug withdrawal events (ADWE), with only limited information available on the incidence, timing and severity of anticholinergic ADWE. We report the case of a 76-year-old woman who experienced significant cognitive improvement following deprescribing long-term use of a strong anticholinergic drug, doxepin, and dose reduction of another possible anticholinergic agent. The patient decided to abruptly stop taking doxepin, despite a planned careful taper with twice weekly monitoring, but did not experience any severe anticholinergic ADWE and subsequently had significantly improved cognitive function. Future research should focus on better understanding the risk of anticholinergic ADWE so that anticholinergic deprescribing decisions, including how often and by how much to taper, can be made confidently and safely.

Extended-Release 7-Day Injectable Buprenorphine for Patients With Minimal to Mild Opioid Withdrawal

Importance

Buprenorphine is an effective yet underused treatment for opioid use disorder (OUD).

Objective

To evaluate the feasibility (acceptability, tolerability, and safety) of 7-day injectable extended-release buprenorphine in patients with minimal to mild opioid withdrawal.

Design, Setting, and Participants

This nonrandomized trial comprising 4 emergency departments in the Northeast, mid-Atlantic, and Pacific geographic areas of the US included adults aged 18 years or older with moderate to severe OUD and Clinical Opiate Withdrawal Scale (COWS) scores less than 8 (minimal to mild), in which scores range from 0 to 7, with higher scores indicating increasing withdrawal. Exclusion criteria included methadone-positive urine, pregnancy, overdose, or required admission. Outcomes were assessed at baseline, daily for 7 days by telephone surveys, and in person at 7 days. Patient recruitment occurred between July 13, 2020, and May 25, 2023.

Intervention

Injection of a 24-mg dose of a weekly extended-release formulation of buprenorphine (CAM2038) and referral for ongoing OUD care.

Main Outcomes and Measures

Primary feasibility outcomes included the number of patients who (1) experienced a 5-point or greater increase in the COWS score or (2) transitioned to moderate or greater withdrawal (COWS score ≥13) within 4 hours of extended-release buprenorphine or (3) experienced precipitated withdrawal within 1 hour of extended-release buprenorphine. Secondary outcomes included injection pain, satisfaction, craving, use of nonprescribed opioids, adverse events, and engagement in OUD treatment.

Results

A total of 100 adult patients were enrolled (mean [SD] age, 36.5 [8.7] years; 72% male). Among the patients, 10 (10.0% [95% CI, 4.9%-17.6%]) experienced a 5-point or greater increase in COWS and 7 (7.0% [95% CI, 2.9%-13.9%]) transitioned to moderate or greater withdrawal within 4 hours, and 2 (2.0% [95% CI, 0.2%-7.0%]) experienced precipitated withdrawal within 1 hour of extended-release buprenorphine. A total of 7 patients (7.0% [95% CI, 2.9%-13.9%]) experienced precipitated withdrawal within 4 hours of extended-release buprenorphine, which included 2 of 63 (3.2%) with a COWS score of 4 to 7 and 5 of 37 (13.5%) with a COWS score of 0 to 3. Site pain scores (based on a total pain score of 10, in which 0 indicated no pain and 10 was the worst possible pain) after injection were low immediately (median, 2.0; range, 0-10.0) and after 4 hours (median, 0; range, 0-10.0). On any given day among those who responded, between 29 (33%) and 31 (43%) patients reported no cravings and between 59 (78%) and 75 (85%) reported no use of opioids; 57 patients (60%) reported no days of opioid use. Improving privacy (62%) and not requiring daily medication (67%) were deemed extremely important. Seventy-three patients (73%) were engaged in OUD treatment on day 7. Five serious adverse events occurred that required hospitalization, of which 2 were associated with medication.

Conclusions and Relevance

This nonrandomized trial of the feasibility of a 7-day buprenorphine injectable in patients with minimal to mild opioid withdrawal (COWS scores, 0-7) found the formulation to be acceptable, well tolerated, and safe in those with COWS scores of 4 to 7. This new medication formulation could substantially increase the number of patients with OUD receiving buprenorphine.

Trial Registration

ClinicalTrials.gov Identifier: NCT04225598.

The "Micro"cosm: Magnifying the Nuance of Low Dose Buprenorphine Inductions

BACKGROUND

Now that the X-wavier is a thing of the past, patients with Opioid Use Disorder (OUD) who previously lacked access to buprenorphine may have access to lower barrier care and may be looking to make the transition from either methadone or illicit fentanyl to buprenorphine. This can be quite challenging and both fentanyl and methadone are hihghly potent drugs and can result in a difficult transtition to buprenorphine.

PURPOSE/HYPOTHESIS

A transition from high potency opioids to buprenorphine is challenging and can cause discomfort or withdrawal in patients. Procedures/data/observations: Patients tend to have a difficult time when undergoing a transition from significant fentanyl use (> 1 bundle/day) or high dose methadone to buprenorphine. Over the last year, we've supported this transition for our hospitalized patients and have learned some tips and tricks to ease the transitions. Through our work we've come up with a strategy to transition patients that includes utilizing full mu agonists while initiating a low dose buprenorphine induction. We have developed an informal protocol for this transition that takes advantage of the flexibility of low dose buprenorphine induction strategies and includes the use of non-opioid adjuvant medications to control symptoms of discomfort and withdrawal.

CONCLUSIONS/APPLICATIONS

A transition from the use of significant fentanyl or high dose methadone to buprenorphine is possible and can take place over a matter of a few days. Such a transition requires careful attention to patient symptoms, availability of as needed short acting opioids, and the judicious use of non-opioid adjuvants.

Piloting a Hospital-Based Rapid Methadone Initiation Protocol for Fentanyl

OBJECTIVES

Treating acute opioid withdrawal and offering medications for opioid use disorder (OUD) is critical. Hospitalization offers a unique opportunity to rapidly initiate methadone for OUD; however, little clinical guidance exists. This report describes our experience during the first 9 months following introduction of a hospital-based rapid methadone initiation protocol.

METHODS

We conducted a retrospective chart review of hospitalized patients with OUD seen by our interprofessional addiction medicine consult service at an urban academic center between December 2022 and August 2023. We identified patients who initiated methadone using the rapid methadone initiation protocol, which includes dose recommendations (maximum 60 mg day 1, 70 mg day 2, 80 mg day 3, 100 mg days 4-7) and strict inclusion and exclusion criteria (end organ failure, arrhythmia, concurrent benzodiazepine or alcohol use, age >65).

RESULTS

There were 171 patients that received methadone for OUD during the study period. Of those, 25 patients (15%) received rapid methadone initiation. The average total daily dose of methadone on days 1-7 was 53.0 mg, 69.2 mg, 75.4 mg, 79.5 mg, 87.1 mg, 92.2 mg, and 96.6 mg, respectively. There were no adverse events requiring holding a dose of scheduled methadone, naloxone administration, or transfer to higher level of care.

CONCLUSIONS

A rapid methadone initiation protocol for OUD can be implemented in the inpatient setting. Patients up-titrated their methadone doses quicker than with traditional induction methods, and there were no serious adverse events. Appropriate patient selection may be important to avoid harms.

Effectiveness of Gabapentin as a Benzodiazepine-Sparing Agent in Alcohol Withdrawal Syndrome

Background and Objectives: Gabapentin has shown promise as a potential agent for the treatment of alcohol withdrawal syndrome. We aimed to evaluate the effectiveness of gabapentin as a benzodiazepine-sparing agent in patients undergoing alcohol withdrawal treatment in all the hospitals of a large tertiary healthcare system. Materials and Methods: Medical records of patients admitted to the hospital for alcohol withdrawal management between 1 January 2020 and 31 August 2022 were reviewed. Patients were divided into two cohorts: benzodiazepine-only treatment who received benzodiazepines as the primary pharmacotherapy and gabapentin adjunctive treatment who received gabapentin in addition to benzodiazepines. The outcomes assessed included the total benzodiazepine dosage administered during the treatment and the length of hospital stay. The statistical models were calibrated to account for various factors. Results: A total of 4364 patients were included in the final analysis. Among these, 79 patients (1.8%) received gabapentin in addition to benzodiazepines, and 4285 patients (98.2%) received benzodiazepines only. Patients administered gabapentin required significantly lower average cumulative benzodiazepine dosages, approximately 17.9% less, compared to those not receiving gabapentin (median 2 mg vs. 4 mg of lorazepam equivalent dose (p < 0.01)). However, there were no significant differences in outcomes between the two groups. Conclusions: Our findings demonstrate that using gabapentin with benzodiazepine was associated with a reduction in the cumulative benzodiazepine dosage for alcohol withdrawal. Considering gabapentin as an adjunctive therapy holds promise for patients with comorbidities who could benefit from reducing benzodiazepine dose. This strategy warrants further investigation.

Rapid induction of transdermal buprenorphine to subcutaneous extended-release buprenorphine for the treatment of opioid use disorder

BACKGROUND

Buprenorphine is an effective and safe treatment for opioid use disorder, but the requirement for moderate opioid withdrawal symptoms to emerge prior to initiation is a significant treatment barrier.

CASE PRESENTATION

We report on two cases of hospitalized patients with severe, active opioid use disorder, in which we initiated treatment with transdermal buprenorphine over 48 h, followed by the administration of a single dose of sublingual buprenorphine/naloxone and then extended-release subcutaneous buprenorphine. The patients did not experience precipitated withdrawal and only had mild withdrawal symptoms.

CONCLUSIONS

This provides preliminary evidence for a rapid induction strategy that may improve tolerability, caregiver burden, and treatment retention as compared to previous induction strategies.

Nelotanserin, a selective 5-HT2A receptor inverse agonist, attenuates aspects of nicotine withdrawal but not reward in mice

Nicotine smoking contributes to many preventable disabilities, diseases and deaths. Targeting nicotine reward and withdrawal is a basis for the majority of smoking cessation pharmacotherapies. Due to the emergence of interest in 5-HT2A receptor modulators for numerous psychiatric disorders, we investigated the effect of nelotanserin, a 5-HT2A receptor inverse agonist, on nicotine reward and withdrawal in ICR mice. In nicotine-dependent mice, nelotanserin dose-dependently reduced somatic signs of nicotine withdrawal and thermal hyperalgesia as measured in the hot plate test. However, nelotanserin had no effect on anxiety-like behavior and failed to reduce nicotine reward as measured in the conditioned place preference test. Our results suggest that inverse agonism of the 5-HT2A receptor may be a feasible novel mechanism for smoking cessation by reducing both physical withdrawal and thermal hyperalgesia associated with nicotine abstinence but may require complementary pharmacotherapies targeting affective and reward-associated decrements to improve cessation outcomes.