Non-abstinent treatment outcomes for cannabis use disorder.

BACKGROUND: Abstinence remains a standard outcome for potential treatment interventions for Cannabis Use Disorder (CUD). However, there needs to be validation of non-abstinent outcomes. This study explores reductions in self-reported days of use as another viable outcome measure using data from three completed randomized placebo-controlled clinical trials of pharmacological interventions for CUD. METHODS: The three trials tested the effect of quetiapine (QTP, n = 113); dronabinol (DRO, n = 156); and lofexidine + dronabinol (LFD, n = 122). Self-reported cannabis use was categorized into three use-groups/week: heavy (5-7 days/week), moderate (2-4 days/week) and light use (0-1 days/week). Multinomial logistic regressions analyzed the treatment by time effect on the likelihood of light and moderate use compared to heavy use in each study. RESULTS: Across the three trials, there was no significant overall time-by-treatment interaction (QTP: p = .06; DRO: p = .15; LFD: p = .21). However, the odds of moderate compared to heavy use were significantly higher in treatment than in placebo groups starting around the midpoint of each trial. No treatment differences were found between the odds of light compared to heavy use. CONCLUSIONS: While study-end abstinence rates have been a standard treatment outcome for CUD trials, reduction from heavy to moderate use has not been standardly assessed. During the last several weeks of each trial, those on active medication were more likely to move from heavy to moderate use, which suggests that certain medications may be more impactful than previously assessed. Future studies should determine if this pattern is associated with less CUD severity and/or improved quality of life.

Guanfacine extended-release for cannabis use disorder: a pilot feasibility trial.

Background: Currently, there are no established pharmacotherapies for cannabis use disorders (CUDs). As a long-acting alpha-2-adrenergic receptor agonist, guanfacine extended-release (G-XR) could be useful in the treatment of CUDs by mitigating withdrawal and improving behavioral control.Objectives: To evaluate the feasibility and tolerability of G-XR as a treatment for CUDs.Methods: In an eight-week open-label outpatient pilot trial, we evaluated the safety and tolerability of G-XR in 22 cannabis dependent individuals. Using 2 different titration schedules, G-XR was gradually titrated to a dose of 4 mg or the highest dose tolerated. All participants received standard medication management.Results: Retention at week eight was 41%. Average daily amount of cannabis use (in grams: F1,86 = 8.74, p = .004; in dollars: F1,86 = 16.67, p < .0001) and cannabis using days (F1,86 = 7.67, p = .007) significantly reduced over the course of study participation. There were no significant differences between the titration schedules on emergence of side effects (Fisher exact test, p = .378) or retention (Log-Rank Test X21 = 0.021, p = .886). A total of 3 participants achieved 3 weeks or greater of total abstinence.Conclusions: G-XR is a feasible treatment for CUDs, and should be evaluated further in an efficacy trial.

Open-label pilot study of injectable naltrexone for cannabis dependence.

BACKGROUND: There are no FDA-approved pharmacotherapies for cannabis use disorders (CUD), despite the evaluation of numerous medications. Notably, chronic dosing of oral naltrexone decreases self-administration of cannabis in human laboratory studies. OBJECTIVES: To test the feasibility of long-acting injectable naltrexone for the treatment of CUD, while obtaining preliminary safety and efficacy data. METHODS: Twelve adult participants (seven male) meeting DSM-IV-TR criteria for cannabis dependence enrolled into an 8-week, open-label pilot study conducted at an academic treatment research clinic. They received 380 mg intramuscular injections of long-acting naltrexone on study day 1 and at the start of study week 5. Outcome measures included percentages of study completers and participants who received the second injection, frequency of adverse events (AEs), and cannabis consumption measured by average daily grams, dollars, and using days per week as measured by timeline follow-back and urine oral delta-9-tetrahydrocannabinol (THC) concentrations. RESULTS: Of the 12 participants enrolled in the study, 9 completed the study and 6 received the second injection. There were no severe AEs but an unexpected AE led to the addition of supportive medications to the protocol. Number of cannabis use days per week significantly decreased over the course of the study (p = .001). Creatinine-corrected urine THC concentrations and average daily cannabis use per study week in grams and in dollars did not decrease over the course of the study. CONCLUSIONS: Long-acting injectable naltrexone is a feasible intervention for CUD worthy of further study in a placebo-controlled, double-blinded randomized clinical trial.

Abstinence and reduced frequency of use are associated with improvements in quality of life among treatment-seekers with cannabis use disorder.

BACKGROUND AND OBJECTIVE: Many patients with cannabis use disorder (CUD) do not achieve or do not have abstinence as a goal of treatment, rather they reduce their use. Assessing outcome measures as they relate to functioning and reductions in cannabis use is an important area of study. Quality of life (QoL) shows promise as one such measure. Past studies have demonstrated gender differences in QoL and CUD. We aim to assess (1) the relationship between cannabis use and QoL and (2) gender effects in an outpatient medication treatment study for CUD. METHODS: Data from an 11-weeks, double-blind, placebo-controlled trial of lofexidine and dronabinol for CUD (n = 62) was analyzed. Pearson's correlations between baseline QoL as measured with the Quality of Life, Enjoyment, and Satisfaction Questionnaire-Short Form (QLES-Q-SF) and cannabis use assessed with modified timeline follow-back (TLFB) were examined. Multiple linear regression models of cannabis use on end of study QLES-Q-SF were analyzed, while adjusting for baseline QLES-Q-SF, study arm, and gender. Moderation effects with gender were also tested. RESULTS: No significant association between baseline cannabis use and QoL was found. End of study abstinence (F1,47 = 8.34, p = .006) and reduced proportion of using days (F1,47 = 9.48, p = .004) were each significantly associated with end of study QoL. Reduction in grams (F1,27 = 0.25, p = .62) was not associated with QoL at end of study. Gender was not a significant moderator. DISCUSSION AND CONCLUSIONS: Abstinence and lower frequency of use are associated with higher QoL, regardless of gender. SCIENTIFIC SIGNIFICANCE: This is the first time QoL has been demonstrated to change over the course of CUD medication treatment. QoL is an important outcome in CUD treatment. TRIAL REGISTRATION: NCT01020019. (Am J Addict 2018;27:101-107).