Pharmacological Treatments for Cocaine Craving: What Is the Way Forward? A Systematic Review

COT-TT vaccine attenuates cocaine-seeking and cocaine-conditioned place preference in rats

Vaccination active, promising alternative immunological strategy to treat of CUD. Various models of cocaine vaccines have been evaluated in animals and humans with relative success. In this sense, it is necessary to improve or optimize the cocaine vaccines already evaluated. Our laboratory previously reported the efficacy of the tetanus toxoid-conjugated morphine vaccine (M6-TT). The M6-TT vaccine can generate high titers of antibodies and reduce heroin-induced behavioral effects in rodents. So, it would be plausible to assume that if we modify the M6-TT vaccine by changing the hapten and maintaining the rest of the structural elements of the vaccine, we will maintain the properties of the M6-TT vaccine (high antibody titers). The objective of this study was to determine whether the antibodies generated by a tetanus toxoid-conjugated cocaine vaccine (COC-TT) can recognize and capture cocaine and decrease the cocaine-induced reinforcing effects. Male Wistar rats were immunized with the COC-TT. A solid-phase antibody-capture ELISA was used to monitor antibody titer responses after each booster dose in vaccinated animals. The study used cocaine self-administration and place-preference testing to evaluate the cocaine-reinforcing effects. The COC-TT vaccine could generate high levels of anti-cocaine antibodies. The antibodies reduced the cocaine self-administration and cocaine place preference. In addition, they decreased the cocaine-induced Fos protein expression. These findings suggest that the COC-TT vaccine generates a robust immunogenic response capable of reducing the reinforcing effects of cocaine, which supports its possible future use in clinical trials in patients with CUD.

Intranasal Delivery of Near-Infrared and Magnetic Dual-Response Nanospheres to Rapidly Produce Antidepressant-Like and Cognitive Enhancement Effects

Restricted by synaptic plasticity, dopamine receptor (DR) upregulation takes a long time to work. Moreover, the impact of the blood-brain barrier (BBB) on delivery efficiency restricts the development of drugs. Taking inspiration from snuff bottles, a convenient, fast-acting, and nonaddictive nasal drug delivery system has been developed to rapidly reshape the balance of synaptic transmitters. This optical and magnetic response system called CFs@DP, comprised of carbonized MIL-100 (Fe) frameworks (CFs) and domperidone (DP), which can enter the brain via nasal administration. Under dual stimulation of near-infrared (NIR) irradiation and catecholamine-induced complexation, CFs@DP disintegrates to release iron ions and DP, causing upregulation of the dopamine type 1 (D1), type 2 (D2) receptors, and brain-derived neurotrophic factor (BDNF) to achieve a therapeutic effect. In vivo experiments demonstrate that the DR density of mice (postnatal day 50-60) increased in the prefrontal cortex (PFC) and the hippocampus (HPC) after 10 days of therapy, resulting in antidepressant-like and cognitive enhancement effects. Interestingly, the cognitive enhancement effect of CFs@DP is even working in noniron deficiency (normal fed) mice, making it a promising candidate for application in enhancing learning ability.

Hospitalized cocaine detoxification patients in Paris, France: Increased patient levels and changing population characteristics since 2011

AIM OF THE STUDY

The past twenty years have seen a rise in cocaine-related statistics in France, including cocaine use in the general population, emergency ward presentations of acute cocaine intoxication, cocaine use disorders related outpatient appointments and cocaine-related deaths. This study's objectives were to describe trends in patients' admission for specific cocaine detoxification as well as changes in patients' characteristics in the Assistance publique-Hôpitaux de Paris (AP-HP) hospitals group located in Paris region, France.

METHODS

We reviewed the international classification of diseases 10th edition (ICD-10) discharge codes of the AP-HP hospitals group between 2011 and 2021. In addition, medical reports of the largest addiction medicine ward were also analysed for changes across the years 2009, 2014, 2019 and 2022.

RESULTS

The regional database showed an almost 3-fold increase in cocaine-related disorders discharge codes between 2011 and 2019. This occurred due to a rise in hospital stays for cocaine dependence or cocaine acute intoxication prior to the fall in levels of inpatient stays associated with the coronavirus disease 2019 (COVID-19) pandemic. The in-depth analysis of inpatients' stays in the specialized addiction medicine ward also showed an increase in admissions for cocaine detoxification programs, with a prevalence of 1.19% in 2009 to 15.73% in 2022 (P=1.44×10-20). Inpatient characteristics showed significant changes, especially in 2022, namely: more daily users, less intravenous administration and less comorbid illicit substances use disorders, with heightened levels of cured hepatitis C patients (P<0.05). Inpatient prescriptions were primarily dopaminergic antagonists with sedatives properties (cyamemazine, loxapine and chlorpromazine), dopamine-receptors partial agonist (aripiprazole) and serotonin reuptake inhibitors.

CONCLUSION

The referral to hospital care for cocaine detoxification has increased in Paris region since 2011, coupled with changes in inpatients' characteristics. This trend has significant implications for the management of inpatient hospital services.

IUPHAR Review: New strategies for medications to treat substance use disorders

Substance use disorders (SUDs) and drug overdose are a public health emergency and safe and effective treatments are urgently needed. Developing new medications to treat them is expensive, time-consuming, and the probability of a compound progressing to clinical trials and obtaining FDA-approval is low. The small number of FDA-approved medications for SUDs reflects the low interest of pharmaceutical companies to invest in this area due to market forces, characteristics of the population (e.g., stigma, and socio-economic and legal disadvantages), and the high bar regulatory agencies set for new medication approval. In consequence, most research on medications is funded by government agencies, such as the National Institute on Drug Abuse (NIDA). Multiple scientific opportunities are emerging that can accelerate the discovery and development of new medications for SUDs. These include fast and efficient tools to screen new molecules, discover new medication targets, use of big data to explore large clinical data sets and artificial intelligence (AI) applications to make predictions, and precision medicine tools to individualize and optimize treatments. This review provides a general description of these new research strategies for the development of medications to treat SUDs with emphasis on the gaps and scientific opportunities. It includes a brief overview of the rising public health toll of SUDs; the justification, challenges, and opportunities to develop new medications; and a discussion of medications and treatment endpoints that are being evaluated with support from NIDA.

Brexpiprazole in patients with schizophrenia with or without substance use disorder: an observational study

Background

Partial dopamine D2 receptor agonists are used for psychotic symptoms in adults with schizophrenia spectrum disorders. Recently, interest surged for partial dopamine D2 receptor agonists in substance use disorders (SUDs). Since it is believed that SUDs decrease the efficacy of pharmacotherapy of underlying psychiatric disorders, we tested the efficacy of the partial D2 agonist brexpiprazole in patients with schizophrenia who were either comorbid with a SUD (SUD group) or not comorbid (non-SUD) to assess treatment response and the effect of brexpiprazole on substance craving in SUD.

Methods

We included patients with DSM-5/DSM-5-TR schizophrenia (using SCID-5-CV) aged 18-66 years with either comorbid SUD or non-SUD to treat with brexpiprazole 4 mg/day for 6 months during February-October 2022. Patients were assessed with the Clinical Global Impressions-Severity (CGI-S) scale, the 24-item Brief Psychiatric Rating Scale (BPRS), and the Positive And Negative Syndrome Scale (PANSS) at baseline, weekly for the first 2 months and monthly for the next four. Furthermore, we assessed substance craving in SUD with a visual analog scale for craving (VAScrav) at the same timepoints.

Results

The total sample was 86 (85 analysable) 18- to 64-year-old (mean 39.32 ± 14.09) patients with schizophrenia [51 men (59.3%) and 35 women (40.7%)], of whom 48 SUD (55.8%) (37 men and 11 women) and 38 non-SUD (44.2%) (14 men and 24 women). No serious or persistent adverse events developed over the study period, but one patient dropped out for subjective akathisia. Results indicated the main effects of time with improvements over the course of the study for CGI-S, BPRS, and PANSS in both SUD and non-SUD groups and the entire sample, and for VAScrav in SUD. Brexpiprazole was associated with similar significant improvements in both groups at the 6 month endpoint compared to baseline.

Conclusion

Treatment with brexpiprazole for 6 months improved psychotic symptoms in patients with schizophrenia, independently from whether they belonged to the SUD or the non-SUD group; hence, SUD comorbidity did not confer treatment resistance to brexpiprazole. Furthermore, in the SUD group, we observed reduced substance craving.

Effects of transcranial magnetic stimulation on cocaine addiction: A systematic review of randomized controlled trials

OBJECTIVE

While pharmacological strategies appear to be ineffective in treating long-term addiction, repetitive transcranial magnetic stimulation (rTMS) is emerging as a promising new tool for the attenuation of craving among multiple substance dependent populations.

METHOD

A systematic review of randomized controlled trials (RCTs) was conducted on the efficacy and tolerability of rTMS in treating cocaine use disorder (CUD). Relevant papers published in English through November 30th 2022 were identified, searching the electronic databases MEDLINE, Embase, PsycINFO and the Cochrane Library.

RESULTS

Eight studies matched inclusion criteria. The best findings were reported by the RCTs conducted at high-frequency (≥5 Hz) multiple sessions of rTMS delivered over the left dorsolateral prefrontal cortex (DLPFC): a significant decrease in self-reported cue-induced cocaine craving and lower cocaine craving scores and a considerable amelioration in the tendency to act rashly under extreme negative emotions (impulsivity) were found in the active group compared to controls.

CONCLUSION

Although still scant and heterogeneous, the strongest evidence so far on the use of rTMS on individuals with CUD support the high frequency stimulation over the left DLPFC as a well tolerated treatment of cocaine craving and impulsivity.

Esketamine Inhibits Cocaine-Seeking Behaviour Subsequent to Various Abstinence Conditions in Rats

BACKGROUND

Cocaine use disorder (CUD) is a relapsing brain disease caused by a chronic drug intake that involves neural mechanisms and psychological processes, including depression. Preclinical and clinical studies have demonstrated the promise of pharmacological drugs in controlling the reinstatement of cocaine by targeting the N-methyl-D-aspartate (NMDA) receptor. Recent evidence has revealed that esketamine, a (S) enantiomer of ketamine, shows a high affinity to NMDA receptors and has been used in clinical trials to treat moderate-to-severe depression.

METHODS

In the present paper, we investigated the effects of esketamine in regulating cocaine-seeking behaviour induced through the use of cocaine (10 mg/kg) or the cocaine-associated conditioned cue after a short (10 days)-lasting period of drug abstinence with extinction training, home cage or enrichment environment conditions in male rats. Furthermore, we investigated the acute effects of esketamine on locomotor activity in drug-naïve animals.

RESULTS

Esketamine (2.5-10 mg/kg) administered peripherally attenuated the reinstatement induced with cocaine priming or the drug-associated conditioned cue after different conditions of abstinence.

CONCLUSIONS

These results seem to support esketamine as a candidate for the pharmacological management of cocaine-seeking and relapse prevention; however, further preclinical and clinical research is needed to better clarify esketamine's actions in CUD.

Unravelling the landscape of Cannabis craving pharmacological treatments: a PRISMA-guided review of evidence

Currently, few treatments are available for craving in general, and none of them have received approval for cannabis craving. The objective of this review is to evaluate existing studies analysing treatments for cannabis craving and explore novel treatment possibilities for these patients. The study followed PRISMA guidelines and conducted an extensive database search. Inclusion criteria included human randomised controlled trials examining drug effects on craving symptoms. Exclusion criteria involved studies unrelated to craving, non-pharmacological treatments, duplicates, and non-English/Spanish/Portuguese articles. Our included 22 studies that investigated a wide range of compounds used for cravings related to other drugs, as well as interventions based on healthcare professionals' empirical knowledge. The current pharmacological treatments largely involve off-label drug use and the utilisation of cannabinoid-based medications, such as combinations of THC and lofexidine, oxytocin, progesterone, and N-acetylcysteine. These emerging treatments show promise and have the potential to revolutionise current clinical practices, but further investigation is needed to establish their efficacy. In this context, it is essential to consider non-pharmacological interventions, such as psychotherapy and behavioural treatments. These approaches play a crucial role in complementing pharmacological interventions and addressing the complex nature of the disorder.

Concomitant Drug Use among Opioid-Dependent Patients with and without Attention Deficit Hyperactivity Disorder: Does Methylphenidate Merit a Trial?

INTRODUCTION

Concomitant drug use is common among opioid-dependent patients in maintenance therapy. Attention deficit hyperactivity disorder (ADHD), a common comorbidity among opioid users, is associated with a higher risk of concomitant drug use. Earlier studies showed that methylphenidate (MPH) can reduce cocaine consumption among patients with ADHD. The use of MPH as an agonist-replacement or maintenance therapy in cocaine-dependent patients without ADHD is also common in Switzerland, despite a lack of supporting evidence. The aim of this study was to assess concomitant cocaine, amphetamine, MDMA, MPH, and heroin use among patients in opioid maintenance therapy either with or without comorbid ADHD. We expected stimulant consumption to be higher in patients with cocaine dependence and comorbid ADHD and that use of MPH would not lead to a reduction in cocaine consumption in patients without ADHD. We therefore evaluated correlations between use of MPH and cocaine consumption and between MPH consumption and cocaine craving within the two groups.

METHODS

This cross-sectional study included 94 opioid-dependent patients in maintenance therapy in an outpatient department of the Psychiatric Hospital of Zurich. The patients were divided into two groups based on comorbid ADHD; a group with ADHD (N = 27) and a group without ADHD (N = 67). Drug use was assessed using 3-month hair analysis.

RESULTS

We did not find significant differences in the number of patients using cocaine, amphetamine, MDMA, or heroin between groups with or without ADHD. With respect to cocaine use, 85.2 percent of patients in the ADHD group and 73.1 percent in the non-ADHD group were users. The non-ADHD group showed a significant positive correlation between the concentration of MPH and cocaine in hair samples (p < 0.05), and a positive correlation between cocaine craving and the concentration of MPH in hair samples (p = 0.065). These two trends were not evident in the ADHD group.

CONCLUSION

Among patients without ADHD, use of MPH correlates with higher cocaine consumption and craving. Conversely, no significant correlation was found between MPH and cocaine use in patients with ADHD. Our study adds to the evidence that MPH confers negative effects in cocaine users without ADHD and should thus have no place in the treatment of these patients.

Deficits in consummatory reward relate to severity of cocaine use

BACKGROUND AND AIMS

Identifying modifiable neuropsychological factors associated with more severe CUD could improve CUD treatment. Impairments in processing of non-drug rewards may be one such factor. This study assessed the relationship between reward functioning and cocaine use severity using multi-modal measures of three distinct reward functions: consummatory reward (pleasure or "liking"); motivational reward ("wanting") and reward learning.

METHODS

Fifty-three adults with at least moderate CUD completed self-report and behavioral measures of consummatory reward, motivational reward and reward learning, and a composite cocaine use severity measure including quantity, frequency and life impacts of cocaine use. We conducted parallel Frequentist and Bayesian multiple regressions with measures of reward functioning as predictors of cocaine use severity.

RESULTS

Less self-reported ability to experience pleasure, a hypothesized measure of consummatory reward, significantly predicted greater severity after adjustment for covariates and multiple hypothesis testing, β = 0.39, t(38) = 2.86, p = 0.007. Bayesian analyses confirmed a highly likely association between severity and ability to experience pleasure, and provided moderate evidence for associations with willingness to exert effort and reward learning.

CONCLUSIONS

Our results suggest that less experience of subjective pleasure is related to greater cocaine use severity. This cross-sectional study cannot establish whether differences in consummatory reward are pre-existing, a result of CUD, or both. However, these results suggest interventions focused on increasing subjective pleasure, such as mindful "savoring", should be investigated for CUD.