Project description:Background and Objectives: Preclinical studies show serotonin (5-HT) 5-HT2C receptor (5-HT2CR) agonists reduce cocaine-seeking and cocaine intake. This study examined safety of the 5-HT2CR agonist lorcaserin administered with cocaine in participants with cocaine use disorder (CocUD). Secondarily, subjective response to cocaine and choice of cocaine vs. money were examined. Methods: A double-blind, randomized, placebo-controlled trial of 25 inpatient non-treatment seeking participants with CocUD. Participants were randomized to either lorcaserin (n = 17) or placebo (n = 8). Primary outcome measures included cardiovascular measures and plasma cocaine levels. Secondary measures of subjective response to cocaine were assessed using a visual analog scale (VAS) and cocaine vs. money progressive ratio choice sessions. Results: Thirteen randomized participants were included in the final analysis. No serious or unexpected adverse events were related to lorcaserin. There were no significant interactions between cocaine and lorcaserin on cardiovascular measures, plasma cocaine, or subjective ratings. After multiple comparisons correction, cocaine significantly increased blood pressure, heart rate, and QTc. Lorcaserin significantly decreased VAS ratings of "feel irritable," "feel hungry," and "I am craving." For the cocaine vs. money choice procedure, there was a significant interaction between choice (cocaine vs. money) and lorcaserin. Participants treated with lorcaserin were more likely to choose cocaine. Discussion and Conclusions: This study showed safety of lorcaserin administered with cocaine but lack of efficacy to reduce the reinforcing effects of cocaine. Scientific Significance: This study is the first to show a disconnect between effects of 5-HT2CR agonists on craving and cocaine choice in human cocaine users.
Project description:ObjectiveTo determine if men who have sex with men (MSM) with cocaine use disorder (CUD) and actively-using cocaine could be enrolled and retained in a pharmacologic intervention trial of lorcaserin-a novel 5-HT2cR agonist-and determine the degree to which participants would adhere to study procedures.MethodsThis was a phase II randomized, double-blind, placebo-controlled pilot study with 2:1 random parallel group assignment to daily extended-release oral lorcaserin 20 mg versus placebo (clinicaltrials.gov identifier-NCT03192995). Twenty-two of a planned 45 cisgender MSM with CUD were enrolled and had weekly follow-up visits during a 12-week treatment period, with substance use counseling, urine specimen collection, and completion of audio-computer assisted self-interview (ACASI) behavioral risk assessments. Adherence was measured by medication event monitoring systems (MEMS) caps and self-report. This study was terminated early because of an FDA safety alert for lorcaserin's long-term use.ResultsEighty-six percent completed the trial, with 82% of weekly study follow-up visits completed. Adherence was 55.3% (lorcaserin 51.6% vs. placebo 66.2%) by MEMS cap and 56.9% (56.5% vs. placebo 57.9%) by self-report and did not differ significantly by treatment assignment. Intention-to-treat analyses (ITT) did not show differences in cocaine positivity by urine screen between the lorcaserin and placebo groups by 12 week follow-up (incidence risk ratio [IRR]: 0.96; 95%CI = 0.24-3.82, P = 0.95). However, self-reported cocaine use in timeline follow-back declined more significantly in the lorcaserin group compared to placebo (IRR: 0.66; 95%CI = 0.49-0.88; P = 0.004).ConclusionWe found that it is feasible, acceptable, and tolerable to conduct a placebo-controlled pharmacologic trial for MSM with CUD who are actively using cocaine. Lorcaserin was not associated with significant reductions in cocaine use by urine testing, but was associated with significant reductions in self-reported cocaine use. Future research may be needed to continue to explore the potential utility of 5-HT2cR agonists.
Project description:ObjectivesCocaine use is on the rise and it is comorbid with marijuana use. We examined the association between lifetime cocaine + marijuana polysubstance use (CM PSU) versus cocaine only and lifetime cocaine use disorder (CocUD) and examined the potential mediation by cocaine use patterns. Methods: A total of 2,968 lifetime cocaine users were identified from the National Epidemiologic Survey on Alcohol and Related Conditions-III. Mediation analysis was utilized to examine cocaine use quantity, frequency, and duration as potential mediators in the association between CM PSU and CocUD. A parallel multiple mediator model and a structural equation model were used, respectively, to examine: (1) the individual contribution of cocaine use quantity, frequency, and duration, and (2) combined contribution as a set specified by a latent variable. Results: Cocaine users were divided into 2,782 (93.7%) CM polysubstance users and 186 (6.3%) cocaine only users. CM PSU was associated with decreased risk of CocUD, but after including the mediators, the association was no longer significant. Examined separately, only quantity was found to be a significant mediator over and above frequency and duration, while the latent variable with three cocaine use pattern indicators explained 56.6% of the total association between CM PSU and CocUD. Conclusions: Compared to cocaine only users, CM polysubstance users were less likely to use cocaine heavily; this lower intensity of cocaine use was in turn associated with decreased risk of CocUD. Future research is warranted to determine the nature of the association between CM PSU and reduced CocUD.
Project description:No pharmacotherapies are approved for the treatment of cocaine use disorder (CUD). Galantamine, a cholinesterase inhibitor, has shown initial promise for cocaine use reduction in methadone-maintained individuals with CUD and cognitive improvement in abstinent individuals with past CUD. However, galantamine has not previously tested in individuals with current CUD and no comorbid opioid use disorder or methadone maintenance. The goal of this 13-week, double-blind, placebo-controlled, randomized controlled trial was to test the efficacy of galantamine (8 mg or 16 mg/day; extended release (ER)) for reducing cocaine use and improving cognitive function in individuals with cocaine use disorder (CUD). Ninety-three treatment-seeking cocaine users were randomized to placebo (n = 32), 8 mg/day galantamine (n = 31) or 16 mg/day galantamine (n = 30). The medication was well-tolerated with minimal reports of side-effects. However, there were no significant treatment group differences in cocaine use outcomes (as measured by self-report or urines). The 16 mg galantamine group had a greater improvement in working memory capacity (Backwards Digit Span), but there were no other significant treatment group differences on key cognitive outcomes. These findings did not provide support for the efficacy of galantamine as a treatment for cocaine use in this sample of individuals with CUD.
Project description:ImportanceAdult attention-deficit/hyperactivity disorder (ADHD) is prevalent but often unrecognized, in part because it tends to co-occur with other disorders such as substance use disorders. Cocaine use disorder is one such disorder with high co-occurrence of ADHD.ObjectiveTo examine whether treatment of co-occurring ADHD and cocaine use disorder with extended-release mixed amphetamine salts is effective at both improving ADHD symptoms and reducing cocaine use.Design, setting, and participantsThirteen-week, randomized, double-blind, 3-arm, placebo-controlled trial of participants meeting DSM-IV-TR criteria for both ADHD and cocaine use disorder conducted between December 1, 2007, and April 15, 2013, at 2 academic health center substance abuse treatment research sites. One hundred twenty-six adults diagnosed as having comorbid ADHD and cocaine use disorder were randomized to extended-release mixed amphetamine salts or placebo. Analysis was by intent-to-treat population.InterventionsParticipants received extended-release mixed amphetamine salts (60 or 80 mg) or placebo daily for 13 weeks and participated in weekly individual cognitive behavioral therapy.Main outcomes and measuresFor ADHD, percentage of participants achieving at least a 30% reduction in ADHD symptom severity, measured by the Adult ADHD Investigator Symptom Rating Scale; for cocaine use, cocaine-negative weeks (by self-report of no cocaine use and weekly benzoylecgonine urine screens) during maintenance medication (weeks 2-13) and percentage of participants achieving abstinence for the last 3 weeks.ResultsMore patients achieved at least a 30% reduction in ADHD symptom severity in the medication groups (60 mg: 30 of 40 participants [75.0%]; odds ratio [OR] = 5.23; 95% CI, 1.98-13.85; P < .001; and 80 mg: 25 of 43 participants [58.1%]; OR = 2.27; 95% CI, 0.94-5.49; P = .07) compared with placebo (17 of 43 participants [39.5%]). The odds of a cocaine-negative week were higher in the 80-mg group (OR = 5.46; 95% CI, 2.25-13.27; P < .001) and 60-mg group (OR = 2.92; 95% CI, 1.15-7.42; P = .02) compared with placebo. Rates of continuous abstinence in the last 3 weeks were greater for the medication groups than the placebo group: 30.2% for the 80-mg group (OR = 11.87; 95% CI, 2.25-62.62; P = .004) and 17.5% for the 60-mg group (OR = 5.85; 95% CI, 1.04-33.04; P = .04) vs 7.0% for placebo.Conclusions and relevanceExtended-release mixed amphetamine salts in robust doses along with cognitive behavioral therapy are effective for treatment of co-occurring ADHD and cocaine use disorder, both improving ADHD symptoms and reducing cocaine use. The data suggest the importance of screening and treatment of ADHD in adults presenting with cocaine use disorder.Trial registrationclinicaltrials.gov Identifier:NCT00553319.
Project description:RationaleDrug addiction has been suggested to develop through drug-induced changes in learning and memory processes. Whilst the initiation of drug use is typically goal-directed and hedonically motivated, over time, drug-taking may develop into a stimulus-driven habit, characterised by persistent use of the drug irrespective of the consequences. Converging lines of evidence suggest that stimulant drugs facilitate the transition of goal-directed into habitual drug-taking, but their contribution to goal-directed learning is less clear. Computational modelling may provide an elegant means for elucidating changes during instrumental learning that may explain enhanced habit formation.ObjectivesWe used formal reinforcement learning algorithms to deconstruct the process of appetitive instrumental learning and to explore potential associations between goal-directed and habitual actions in patients with cocaine use disorder (CUD).MethodsWe re-analysed appetitive instrumental learning data in 55 healthy control volunteers and 70 CUD patients by applying a reinforcement learning model within a hierarchical Bayesian framework. We used a regression model to determine the influence of learning parameters and variations in brain structure on subsequent habit formation.ResultsPoor instrumental learning performance in CUD patients was largely determined by difficulties with learning from feedback, as reflected by a significantly reduced learning rate. Subsequent formation of habitual response patterns was partly explained by group status and individual variation in reinforcement sensitivity. White matter integrity within goal-directed networks was only associated with performance parameters in controls but not in CUD patients.ConclusionsOur data indicate that impairments in reinforcement learning are insufficient to account for enhanced habitual responding in CUD.
Project description:BackgroundDrug-induced alterations to the dopamine system in stimulant use disorder (SUD) are hypothesized to impair reinforcement learning (RL). Computational modeling enables the investigation of the latent processes of RL in SUD patients, which could elucidate the nature of their impairments.MethodsWe investigated RL in 44 SUD patients and 41 healthy control participants using a probabilistic RL task that assesses learning from reward and punishment separately. In an independent sample, we determined the modulatory role of dopamine in RL following a single dose of the dopamine D2/3 receptor antagonist amisulpride (400 mg) and the agonist pramipexole (0.5 mg) in a randomised, double-blind, placebo-controlled, crossover design. We analyzed task performance using computational modelling and hypothesized that RL impairments in SUD patients would be differentially modulated by a dopamine D2/3 receptor antagonist and agonist.ResultsComputational analyses in both samples revealed significantly reduced learning rates from punishment in SUD patients compared with healthy controls, whilst their reward learning rates were not measurably impaired. In addition, the dopaminergic receptor agents modulated RL parameters differentially in both groups. Both amisulpride and pramipexole impaired RL parameters in healthy participants, but ameliorated learning from punishment in SUD patients.ConclusionOur findings suggest that RL impairments seen in SUD patients are associated with altered dopamine function.
Project description:Background/aimsCocaine use disorder (CUD) persists as a major public health problem in the United States. Response to evidence-based behavioral treatment has been shown to be predicted by dopaminergic dysfunction. Amphetamine formulations modulate dopaminergic systems and are one of the few agents with positive clinical findings but are associated with unique risks. We aimed to find a model for determining the most appropriate patients for treatment with mixed amphetamine salts-extended-release (MAS-ER) for CUD using an adaptive trial design.MethodsWe are enrolling treatment-seeking adults ages 18-60 years. All eligible participants receive bi-weekly individual counseling augmented with a computer-based intervention based on the community reinforcement approach with contingency management (CRA + CM) for 4 weeks. Participants who fail to achieve abstinence are additionally randomly assigned to 10 weeks of either MAS-ER, titrated up to 80 mg daily, or placebo. All participants complete a follow-up assessment after 12 weeks.ResultsFrequency and amount of cocaine use, cravings, retention, and quality of life will be compared between groups. The primary outcome will be having at least 3 weeks of urine toxicology-confirmed self-reported abstinence. Analyses will also be conducted to identify variables that may help identify who is more or less likely respond to the behavioral intervention during the first 4-weeks of treatment.ConclusionsThis trial more closely mimics a personalized medicine approach that is often used in clinical practice. It will help us understand who may be appropriate for psychostimulant therapy as an enhancement to evidence-based behavioral interventions, while limiting exposure to those who would respond to a psychosocial intervention alone. ClinicalTrials.gov Identifier: NCT01986075.
Project description:Cocaine use disorder (CUD) is an intractable syndrome, and rising overdose death rates represent a significant public health crisis that exacts tremendous personal and financial costs on patients and society. Sharp increases in cocaine use drive the urgent need for better mechanistic insight into this chronic relapsing brain disorder that currently lacks effective treatment options. To investigate the transcriptomic changes involved, we conducted RNA sequencing on two striatal brain regions that are heavily implicated in CUD, the nucleus accumbens and caudate nucleus, from postmortem brains of subjects with CUD and matched control subjects. Weighted gene co-expression analyses identified CUD-specific gene networks enriched in ionotropic receptors and associated with lowered neuroinflammation, contrasting the proinflammatory responses found in opioid use disorder. Integration of comprehensive transcriptomic datasets from mouse cocaine self-administration models revealed evolutionarily conserved gene networks in CUD that implicate especially D1 medium spiny neurons as drivers of cocaine-induced plasticity.
Project description:BackgroundOpioid Use Disorder (OUD) is a significant public health problem associated with severe morbidity and mortality. While effective pharmacotherapies are available, limitations exist with each. Induction onto extended-release naltrexone (XR-NTX) is more difficult than initiation of buprenorphine or methadone, even in inpatient settings, as it is recommended that patients remain abstinent for at least 7 days prior to initiating XR-NTX. The purpose of this trial was to determine if lorcaserin, a 5HT2c agonist, improves outpatient XR-NTX induction rates.MethodsAn 8-week trial beginning with a brief detoxification period and induction onto XR-NTX. Sixty participants with OUD were enrolled in the trial, with 49 participants at the initiation of detoxification randomized to lorcaserin or placebo for 39 days. Additionally, ancillary medications were provided. The primary outcome was the proportion of participants inducted onto the first XR-NTX injection. Secondary outcomes were withdrawal severity (measured by COWS and SOWS) prior to the first injection and the proportion of participants receiving the second XR-NTX injection.ResultsThe proportion of participants inducted onto the first (lorcaserin: 36 %; placebo: 44 %; p = .67) and the second XR-NTX injection (lorcaserin: 27 %; placebo: 31 %; p = .77) was not significantly different between treatment arms. Prior to the first injection, withdrawal scores did not significantly differ between treatment arms over time (treatment*time interaction COWS: p = .11; SOWS: p = .39).ConclusionsLorcaserin failed to improve outpatient XR-NTX induction rates. Although this study is small, the findings do not support the use of lorcaserin in promoting induction onto XR-NTX or in mitigating withdrawal symptoms.