Edward V. Nunes

Injectable extended-release naltrexone for opioid dependence: a double-blind, placebo-controlled, multicentre randomised trial

BACKGROUND Opioid dependence is associated with low rates of treatment-seeking, poor adherence to treatment, frequent relapse, and major societal consequences. We aimed to assess the efficacy, safety, and patient-reported outcomes of an injectable, once monthly extended-release formulation of the opioid antagonist naltrexone (XR-NTX) for treatment of patients with opioid dependence after detoxification. METHODS We did a double-blind, placebo-controlled, randomised, 24-week trial of patients with opioid dependence disorder. Patients aged 18 years or over who had 30 days or less of inpatient detoxification and 7 days or more off all opioids were enrolled at 13 clinical sites in Russia. We randomly assigned patients (1:1) to either 380 mg XR-NTX or placebo by an interactive voice response system, stratified by site and gender in a centralised, permuted-block method. Participants also received 12 biweekly counselling sessions. Participants, investigators, staff , and the sponsor were masked to treatment allocation. The primary endpoint was the response profile for confirmed abstinence during weeks 5–24, assessed by urine drug tests and self report of non-use. Secondary endpoints were self-reported opioid-free days, opioid craving scores, number of days of retention, and relapse to physiological opioid dependence. Analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00678418. FINDINGS Between July 3, 2008, and Oct 5, 2009, 250 patients were randomly assigned to XR-NTX (n=126) or placebo (n=124). The median proportion of weeks of confirmed abstinence was 90·0% (95% CI 69·9–92·4) in the XR-NTX group compared with 35·0% (11·4–63·8) in the placebo group (p=0·0002). Patients in the XR-NTX group self-reported a median of 99·2% (range 89·1–99·4) opioid-free days compared with 60·4% (46·2–94·0) for the placebo group (p=0·0004). The mean change in craving was –10·1 (95% CI –12·3 to –7·8) in the XR-NTX group compared with 0·7 (–3·1 to 4·4) in the placebo group (p<0·0001). Median retention was over 168 days in the XR-NTX group compared with 96 days (95% CI 63–165) in the placebo group (p=0·0042). Naloxone challenge confirmed relapse to physiological opioid dependence in 17 patients in the placebo group compared with one in the XR-NTX group (p<0·0001). XR-NTX was well tolerated. Two patients in each group discontinued owing to adverse events. No XR-NTX-treated patients died, overdosed, or discontinued owing to severe adverse events. INTERPRETATION XR-NTX represents a new treatment option that is distinct from opioid agonist maintenance treatment. XR-NTX in conjunction with psychosocial treatment might improve acceptance of opioid dependence pharmacotherapy and provide a useful treatment option for many patients. FUNDING Alkermes.

Cognitive impairment, retention and abstinence among cocaine abusers in cognitive-behavioral treatment.

Cognitive-behavioral therapy (CBT) depends on adequate cognitive functioning in patients, but prolonged cocaine use may impair cognitive functioning. Therefore, cognitive impairment may impede the ability of cocaine abusers to benefit from CBT. To begin to address this issue, we investigated the relationship between cognitive impairment and two treatment outcomes, therapy completion and abstention. Eighteen carefully screened non-depressed cocaine-dependent patients in a psychopharmacological clinical trial were administered the MicroCog computerized battery to assess cognitive performance at treatment entry. T-tests were used to compare cognitive functioning between completers (patients remaining in treatment at least 12 weeks) and dropouts. The results indicated that treatment completers had demonstrated significantly better cognitive performance at baseline than patients who dropped out of treatment. Cognitive domains that significantly distinguished between treatment completers and dropouts were attention, mental reasoning and spatial processing. This study provides preliminary evidence that cognitive impairments may decrease treatment retention and abstinence in CBT of cocaine dependence.

Rates of psychiatric comorbidity among U.S. residents with lifetime cannabis dependence

Cannabis is the most widely used illegal drug in the U.S. population. Surveys have estimated that the lifetime prevalence rate for cannabis dependence is approximately 4%. Though the presence of a psychiatric disorder increases the likelihood of developing substance dependence, the field lacks data regarding the association between mental disorders and cannabis dependence. The aim of this study is to describe the prevalence of psychiatric disorders among individuals with cannabis dependence. The National Comorbidity Survey was used to obtain these data. We found that 90% of respondents with cannabis dependence had a lifetime mental disorder, compared to 55% without cannabis dependence. Alcohol dependence, antisocial personality disorder, and conduct disorder had the strongest associations with cannabis dependence, followed by anxiety and mood disorders. A large proportion of respondents with internalizing disorders developed mood or anxiety disorders prior to onset of their first cannabis dependence symptom. Data regarding the prevalence of comorbid mental disorders underscore the importance of thorough and systematic evaluation of patients seeking treatment for cannabis dependence. The failure to identify comorbidity may lead to inadequate treatment, and a poorer prognosis.

Do Treatment Improvements in PTSD Severity Affect Substance Use Outcomes? A Secondary Analysis From a Randomized Clinical Trial in NIDA's Clinical Trials Network

OBJECTIVE The purpose of the analysis was to examine the temporal course of improvement in symptoms of posttraumatic stress disorder (PTSD) and substance use disorder among women in outpatient substance abuse treatment. METHOD Participants were 353 women randomly assigned to 12 sessions of either trauma-focused or health education group treatment. PTSD and substance use assessments were conducted during treatment and posttreatment at 1 week and after 3, 6, and 12 months. A continuous Markov model was fit on four defined response categories (nonresponse, substance use response, PTSD response, or global response [improvement in both PTSD and substance use]) to investigate the temporal association between improvement in PTSD and substance use symptom severity during the studys treatment phase. A generalized linear model was applied to test this relationship over the follow-up period. RESULTS Subjects exhibiting nonresponse, substance use response, or global response tended to maintain original classification; subjects exhibiting PTSD response were significantly more likely to transition to global response over time, indicating maintained PTSD improvement was associated with subsequent substance use improvement. Trauma-focused treatment was significantly more effective than health education in achieving substance use improvement, but only among those who were heavy substance users at baseline and had achieved significant PTSD reductions. CONCLUSIONS PTSD severity reductions were more likely to be associated with substance use improvement, with minimal evidence of substance use symptom reduction improving PTSD symptoms. Results support the self-medication model of coping with PTSD symptoms and an empirical basis for integrated interventions for improved substance use outcomes in patients with severe symptoms.

Multisite Randomized Trial of Behavioral Interventions for Women With Co-Occurring PTSD and Substance Use Disorders

The authors compared the effectiveness of the Seeking Safety group, cognitive-behavioral treatment for substance use disorder and posttraumatic stress disorder (PTSD), to an active comparison health education group (Womens Health Education [WHE]) within the National Institute on Drug Abuses Clinical Trials Network. The authors randomized 353 women to receive 12 sessions of Seeking Safety (M = 6.2 sessions) or WHE (M = 6.0 sessions) with follow-up assessment 1 week and 3, 6, and 12 months posttreatment. Primary outcomes were the Clinician Administered PTSD Scale (CAPS), the PTSD Symptom Scale-Self Report (PSS-SR), and a substance use inventory (self-reported abstinence and percentage of days of use over 7 days). Intention-to-treat analysis showed large, clinically significant reductions in CAPS and PSS-SR symptoms (d = 1.94 and 1.12, respectively) but no reliable difference between conditions. Substance use outcomes were not significantly different over time between the two treatments and at follow-up showed no significant change from baseline. Study results do not favor Seeking Safety over WHE as an adjunct to substance use disorder treatment for women with PTSD and reflect considerable opportunity to improve clinical outcomes in community-based treatments for these co-occurring conditions.

Imaging dopamine transmission in cocaine dependence: link between neurochemistry and response to treatment.

OBJECTIVE Previous research has shown that dopamine signaling in the limbic striatum is crucial for selecting adaptive, motivated behavior and that disrupted dopamine transmission is associated with impulsive and maladaptive behavior. In humans, positron emission tomography (PET) imaging studies have shown that cocaine dependence is associated with the dysregulation of striatal dopamine signaling, which is linked to cocaine-seeking behavior. The goal of the present study was to investigate whether this association applies to the treatment setting. The authors hypothesized that dopamine signaling in the limbic striatum would be associated with response to a behavioral treatment that uses positive reinforcement to replace impulsive cocaine use with constructive personal goals. METHOD Prior to treatment, cocaine-dependent subjects underwent two PET scans using [(11)C]raclopride, before and after the administration of a stimulant (methylphenidate), for measurement of striatal dopamine D(2/3) receptor binding and presynaptic dopamine release. RESULTS Both of the outcome measures were lower in the volunteers who did not respond to treatment than in those who experienced a positive treatment response. CONCLUSIONS These findings provide insight into the neurochemistry of treatment response and show that low dopamine transmission is associated with treatment failure. In addition, these data suggest that the combination of behavioral treatment with methods that increase striatal dopamine signaling might serve as a therapeutic strategy for cocaine dependence.

Patient Factors Related to Early Attrition from an Outpatient Cocaine Research Clinic

The dropout rates among cocaine abusers in outpatient treatment programs have averaged 55%. We sought to find patient predictor variables associated with early attrition. Dropouts were more likely to be African-American or Hispanic-American, younger, with an earlier onset of substance abuse. Among minorities, those with more education were less likely to drop out. Patients who were less educated and smoked or injected cocaine were particularly prone to discontinue treatment prematurely. The implications of these findings, and promising interventions for reducing the dropout problem, are discussed.

Posttraumatic stress disorder and short-term outcome in early methadone treatment

The aim of this study was to determine treatment adherence relative to frequency of violence and posttraumatic stress disorders (PTSD) among new methadone patients. Ninety-six opiate-abusing patients were evaluated for childhood physical and sexual abuse (CPSA), adulthood exposures to violence (ADVIOL), PTSD, and treatment adherence. Overall, 43% of the subjects dropped out of treatment within 3 months of intake. Occurrence of trauma or PTSD did not predict drop-out rates. A 2 (Gender) x 2 (PTSD) analysis of covariance (ANCOVA) with severity of other drug use on admission as a covariate, however, revealed a main effect for PTSD, F(4, 71) = 7. 69, p < or =.01, such that those patients with current PTSD revealed significantly more ongoing drug use at 3 months (M = 24.3, SD = 20. 9) than those without (M = 8.9, SD = 11.8). Examination of ongoing cocaine use using a 2 (Gender) x 2 (PTSD) ANCOVA also revealed a main effect for PTSD, F(4, 17) = 8.24, p < or = .005, such that those patients with current PTSD revealed significantly more ongoing cocaine use at 3 months postadmission (M = 51.6, SD = 37.6) than those without (M = 24.3, SD = 20.9). For both genders, CPSA and ADVIOL were associated with higher rates of PTSD, which in turn predicted poorer treatment adherence as measured by ongoing co-occurring drug abuse 3 months postadmission. Results underscore the need for routine assessment and targeted treatment of trauma in methadone patients.

Treatment of depression in patients with opiate dependence

Depression is common among opiate-dependent patients and has been associated with worse prognosis. This article reviews the literature on treatment of depressive disorders and symptoms among patients with opiate dependence. Depression bears a complex relationship to opiate dependence and may represent an independent disorder or may be engendered by psychosocial stress or toxic and withdrawal effects of drugs. Primary treatments for opiate dependence (e.g., methadone or buprenorphine maintenance or residential treatment) are associated with substantial improvements in depression. Studies of antidepressant medications have produced mixed results, some positive but more negative. It is not clear what accounts for these differences, and more research is needed to determine how to select opiate-dependent patients most likely to benefit from antidepressants. Fewer studies have examined psychosocial or behavioral interventions, but some of these also show promise. The data suggest a stepped model of care in which depression is evaluated and observed during the outset of treatment for opiate dependence and if it does not improve, specific psychosocial interventions or antidepressant medications tried. Research is needed on such integrated models of care and treatment algorithms to determine their efficacy and cost effectiveness.

Dronabinol for the treatment of cannabis dependence: A randomized, double-blind, placebo-controlled trial

Cannabis dependence is a substantial public health problem. Behavioral treatments have shown promise, but there are no effective medications for cannabis dependence. The purpose of this study was to evaluate the safety and efficacy of dronabinol, a synthetic form of delta-9-tetrahydrocannabinol, a naturally occurring pharmacologically active component of marijuana, in treating cannabis dependence. 156 cannabis-dependent adults were enrolled in a randomized, double-blind, placebo-controlled, 12-week trial. After a 1-week placebo lead-in phase, participants were randomized to receive dronabinol 20mg twice a day or placebo. Doses were maintained until the end of week 8 and then tapered off over 2 weeks. All participants received weekly motivational enhancement and relapse prevention therapy. Marijuana use was assessed using the timeline follow back method. There was no significant difference between treatment groups in the proportion of participants who achieved 2 weeks of abstinence at the end of the maintenance phase (dronabinol: 17.7%; placebo: 15.6%). Although both groups showed a reduction in marijuana use over time, there were no differences between the groups. Treatment retention was significantly higher at the end of the maintenance phase on dronabinol (77%), compared to placebo (61%) (P=.02), and withdrawal symptoms were significantly lower on dronabinol than placebo (P=.02). This is the first trial using an agonist substitution strategy for treatment of cannabis dependence. Dronabinol showed promise, it was well-tolerated, and improved treatment retention and withdrawal symptoms. Future trials might test higher doses, combinations of dronabinol with other medications with complementary mechanisms, or with more potent behavioral interventions.