A randomized,double-blind,placebo-controlled phase III trial of duloxetine in Japanese fibromyalgia patients

IntroductionFibromyalgia is characterized by widespread pain and is often accompanied by accessory symptoms. There are limited treatment options for this condition in Japan. Therefore, we conducted a phase III study to assess the efficacy and safety of duloxetine in Japanese patients with fibromyalgia.MethodsThis randomized, double-blind, placebo-controlled, parallel-group trial was conducted in Japan. Outpatients who met the American College of Rheumatology 1990 criteria for fibromyalgia and whose Brief Pain Inventory (BPI) average pain score was ≥4 were randomized to duloxetine 60 mg or placebo once daily for 14 weeks. The primary efficacy measure was the change in the BPI average pain score from baseline. Secondary efficacy, quality of life (QoL), and safety outcomes were also evaluated. Mixed-effects model repeated-measures (MMRM) analysis and last observation carried forward (LOCF) analysis of covariance were used to evaluate the primary efficacy measure.ResultsOverall, 393 patients were randomized to receive either duloxetine (n = 196) or placebo (n = 197). The MMRM analysis revealed no significant difference between duloxetine and placebo regarding the change in BPI average pain scores at week 14. Based on LOCF analysis, a statistically significant improvement in the change in BPI average pain scores at week 14 was observed for patients treated with duloxetine compared with placebo. Duloxetine treatment was associated with improved outcomes in nearly all secondary and post hoc analyses. The treatment was generally well tolerated. Somnolence, nausea, and constipation were the most common treatment-emergent adverse events in the duloxetine group. The discontinuation rates due to treatment-emergent adverse events were similar in both groups.ConclusionsAlthough the MMRM analysis did not demonstrate superiority of duloxetine over placebo, duloxetine treatment was associated with improved outcomes in secondary and post hoc analyses of the mean change in the BPI average pain score and most of the secondary outcomes, including analgesia and QoL. Duloxetine treatment was safe and well tolerated. These results suggest that duloxetine treatment could be associated with improvements in pain relief and QoL in Japanese patients with fibromyalgia.

Trial registration

ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT01552057","term_id":"NCT01552057"}}NCT01552057. Registered 9 March 2012.     

Effect of eplerenone on parathyroid hormone levels in patients with primary hyperparathyroidism: a randomized, double-blind, placebo-controlled trial

ABSTRACT: BACKGROUND: Increasing evidence suggests the bidirectional interplay between parathyroid hormone and aldosterone as an important mechanism behind the increased risk of cardiovascular damage and bone disease observed in primary hyperparathyroidism. Our primary object is to assess the efficacy of the mineralocorticoid receptor-blocker eplerenone to reduce parathyroid hormone secretion in patients with parathyroid hormone excess. Methods/design Overall, 110 adult male and female patients with primary hyperparathyroidism will be randomly assigned to eplerenone (25 mg once daily for 4 weeks and 4 weeks with 50 mg once daily after dose titration] or placebo, over eight weeks. Each participant will undergo detailed clinical assessment, including anthropometric evaluation, 24-h ambulatory arterial blood pressure monitoring, echocardiography, kidney function and detailed laboratory determination of biomarkers of bone metabolism and cardiovascular disease. The study comprises the following exploratory endpoints: mean change from baseline to week eight in (1) parathyroid hormone(1--84) as the primary endpoint and (2) 24-hour systolic and diastolic ambulatory blood pressure levels, NT-pro-BNP, biomarkers of bone metabolism, 24 hours urinary protein/albumin excretion and echocardiographic parameters reflecting systolic and diastolic function as well as cardiac dimensions, as secondary endpoints. DISCUSSION: In view of the reciprocal interaction between aldosterone and parathyroid hormone and the potentially ensuing target organ damage, the EPATH trial is designed to determine whether eplerenone, compared to placebo, will effectively impact on parathyroid hormone secretion and improve cardiovascular and bone health in patients with primary hyperparathyroidism. Trial registration ISRCTN33941607.     

Efficacy of cranberry juice on Helicobacter pylori infection: a double-blind, randomized placebo-controlled trial

BACKGROUND: Helicobacter pylori infection is a major cause of peptic ulcer disease and gastric cancer. This study postulated that cranberry juice would be effective in the suppression of H. pylori in an endemically infected population at high risk for gastric cancer. MATERIALS AND METHODS: A prospective, randomized, double-blind, placebo-controlled trial was conducted in Linqu County of Shandong Province, China, where 189 adults aged 48.9 +/- 11.2 years (mean +/- SD) with H. pylori infection were randomly divided into two groups: cranberry juice (n = 97) and placebo (n = 92). Participants were assigned to orally receive two 250-ml juice boxes of cranberry juice or matching placebo beverage daily for 90 days. The degree of H. pylori infection was determined using the 13C-urea breath test before randomization at 35 and 90 days of intervention to assess the efficacy of cranberry juice in alleviating infection. RESULTS: A total of 189 subjects with positive 13C-urea breath test results prior to randomization completed the study. At day 35 of intervention, 14 of the 97 (14.43%) from the the cranberry juice treatment group and 5 of the 92 (5.44%) of the placebo recipients had negative 13C-urea breath test results. After 90 days, the study concluded that 14 of the 97 subjects in the cranberry juice treatment group versus 5 of the 92 in the placebo group yielded negative test results. Eleven individuals from the cranberry juice treatment group and only two from the placebo group were negative at 35 and 90 days of experiment. These results are significant (p < .05). CONCLUSIONS: Regular consumption of cranberry juice can suppress H. pylori infection in endemically afflicted populations.     

Regulation of inflammatory biomarkers by intravenous methylprednisolone in pediatric ARDS patients: Results from a double-blind,placebo-controlled randomized pilot trial

ObjectiveA double-blind, randomized controlled trial showed that low-dose glucocorticoid therapy in pediatric ARDS patients is feasible and may improve both ventilation and oxygenation indices in these patients. However, the molecular mechanisms underlying potential changes in outcomes remain unclear. Based on these clinical findings, this study was designed to examine the effects of intravenous methylprednisolone on circulating inflammatory biomarkers in pediatric ARDS patients.DesignDouble-blind, placebo-controlled randomized trial with blood collection on study entry and day 7.SettingTertiary care children’s hospital.PatientsChildren (0–18 years) with ARDS undergoing mechanical ventilation.Interventions35 children were randomized within 72 h of mechanical ventilation. The glucocorticoid group received methylprednisolone 2 mg/kg loading dose followed by 1 mg/kg/day continuous infusion from days 1 to 7. Both groups were ventilated following the ARDSnet recommendations. WBC and differential cell counts, plasma cytokines and CRP levels, and coagulation parameters were analyzed on days 0 and 7.ResultsAt study entry, the placebo group had higher IL-15 and basophil levels. On day 7, in comparison to study entry, the placebo group had lower IL-1α, IFN-γ and IL-10 levels. The glucocorticoid group had lower INF-α, IL-6, IL-10, MCP-1, G-CSF and GM-CSF levels, and higher IL-17α levels on day 7 in comparison to study entry. Total and differential cell counts remained unchanged within the placebo group between days 0 and 7, whereas in the glucocorticoid group total WBC and platelets counts were increased on day 7. Pearson’s correlation studies within the placebo and glucocorticoid groups revealed positive and negative correlations between cytokine levels, cell counts, coagulation parameters and relevant clinical parameters of disease severity identified in our previous study. Multiple regression models identified several cytokines as predictors for alterations in clinical parameters of disease severity.ConclusionThis pilot study shows the feasibility of simultaneously measuring multiple inflammatory cytokines, cell counts and coagulation parameters in pediatric ARDS patients. We report statistical models that may be useful for future, larger trials to predict ARDS severity and outcomes.     

Antipyretic effect of ibuprofen in Gabonese children with uncomplicated falciparum malaria: a randomized, double-blind, placebo-controlled trial

Background

The protection afforded by human erythrocyte polymorphisms against the malaria parasite, Plasmodium falciparum, has been proposed to be due to reduced ability of the parasite to invade or develop in erythrocytes. If this were the case, variable levels of parasitaemia and rates of seroconversion to infected-erythrocyte variant surface antigens (VSA) should be seen in different host genotypes.

Methods

To test this hypothesis, P. falciparum parasitaemia and anti-VSA antibody levels were measured in a cohort of 555 asymptomatic children from an area of intense malaria transmission in Papua New Guinea. Linear mixed models were used to investigate the effect of α⁺-thalassaemia, complement receptor-1 and south-east Asian ovalocytosis, as well as glucose-6-phosphate dehydrogenase deficiency and ABO blood group on parasitaemia and age-specific seroconversion to VSA.

Results

No host polymorphism showed a significant association with both parasite prevalence/density and age-specific seroconversion to VSA.

Conclusion

Host erythrocyte polymorphisms commonly found in Papua New Guinea do not effect exposure to blood stage P. falciparum infection. This contrasts with data for sickle cell trait and highlights that the above-mentioned polymorphisms may confer protection against malaria via distinct mechanisms.     

A randomized, placebo-controlled, double-blind clinical trial of curcuminoids in oral lichen planus.

We studied the efficacy of curcuminoids in the treatment of oral lichen planus (OLP), a chronic, mucocutaneous, immunological disease. Curcuminoids are components of turmeric (Curcuma longa) that have anti-inflammatory activity. Turmeric has been used in Ayurveda (Indian traditional medicine) for centuries. A randomized, double-blind, placebo-controlled trial was conducted. In all, 100 consecutive, eligible patients with OLP presenting to the oral medicine clinic at the University of California, San Francisco, were to be selected. Two interim analyses were to be conducted during the trial. The trial was conducted between February 2003 and September 2004. The first interim analysis was conducted in October 2004 using data from the first 33 subjects. Study subjects were randomized to receive either placebo or curcuminoids at 2000 mg/day for 7 weeks. In addition, all subjects received prednisone at 60 mg/day for the first 1 week. The primary outcome was a change in symptoms from baseline. Secondary outcomes were changes in clinical signs and occurrence of side effects. The first interim analysis did not show a significant difference between the placebo and curcuminoids groups. Conditional power calculations suggested a less than 2% chance that the curcuminoids group would have a significantly better outcome as compared with the placebo group if the trial were continued to completion. Therefore, the study was ended early for futility. Reaching a conclusion regarding the efficacy of curcuminoids based on the results of this study is not possible as it was ended early for futility. Curcuminoids at this dose were well tolerated and the results suggest that for future studies a larger sample size, a higher dose and/or longer duration of curcuminoids administration should be considered; however, for the next step, an RCT of a shorter duration, using a higher dose of curcuminoids, and without an initial course of prednisone, should be considered.     

Suppression of DNA damage in human peripheral blood lymphocytes by a juice concentrate: a randomized, double-blind, placebo-controlled trial

Chronic inflammation contributes to many prevalent diseases worldwide, and it is widely accepted that inflammatory molecules contribute to DNA damage. In this ancillary study, we investigated the influence of an encapsulated fruit and vegetable juice powder concentrate on peripheral blood lymphocytes (PBL) DNA damage. Using a double-blind, placebo-controlled approach, subjects were randomly assigned capsules containing placebo, or one of two formulations of the juice powder. Blood was drawn at baseline and after 60 days of capsule consumption. We found DNA damage in isolated PBL is suppressed after consumption of the encapsulated juice powder, and damage was correlated with the level of systemic inflammation. These data suggest a potential health benefit by consuming the juice concentrate capsules through their ability to suppress DNA damage as measured in surrogate tissues (PBL).     

The effect of fish oil on physical aggression in schoolchildren--a randomized, double-blind, placebo-controlled trial

OBJECTIVES: The aim of the study was to investigate whether fish oil supplementation affected Japanese schoolchildren's behavior, with changes in aggression over time as the primary endpoint. DESIGN AND SUBJECTS: A placebo-controlled double-blind study with 166 schoolchildren 9-12 years of age was performed. The subjects of the fish oil group (n=83) took fish oil-fortified foods (bread, sausage and spaghetti). These foods were provided in amounts such that each subject in the fish oil group had an intake of 3600 mg of docosahexaenoic acid+840 mg of eicosapentaenoic acid (EPA)/week for 3 months. The rest (the controls, n=83) took control supplements. At the start and end of the study, psychological tests were performed to assess their aggression. RESULTS: Physical aggression assessed by Hostility-Aggression Questionnaire for Children in girls increased significantly (median: 13 to 15, n=42) in the control group and did not change (13 to 13, n=43) in the fish oil group with a significant intergroup difference (P=.008) with baseline as covariate. The changes in physical aggression scores over time and those of the ratio of EPA/arachidonic acid in RBC (DeltaEPA/AA) were significantly correlated in girls who agreed to blood collection (r=-.53, P=.01, n=23). On the contrary, there were no significant changes in physical aggression in boys. Aggression against others (extraggression) assessed by Picture Frustration Study did not change in the control group (median: 5 to 5) but increased significantly in the fish oil group (4 to 5) with a significant intergroup difference (P=.02) with baseline as covariate. These changes in extraggression might be explained partly by significantly lower baseline values of extraggression in the fish oil group (P=.02) than in the control group. There were no significant correlations between Deltaextraggression and DeltaEPA/AA in blood-sampled children (n=49). Impulsivity of girls assessed by parents/guardians using the diagnostic criteria for attention deficit/hyperactivity disorder of DSM-IV was reduced in the fish oil group (1 to 0) with a significant (P=.008) intergroup difference from the control group (1 to 1). There were no significant correlations between Deltaimpulsivity and DeltaEPA/AA in blood-sampled girls. In males, impulsivity reduced in both groups without any intergroup differences. CONCLUSION: There is a possibility that changes in fatty acid nutrition might affect physical aggression especially in girls.     

Daily consumption of tea catechins improves aerobic capacity in healthy male adults: a randomized double-blind,placebo-controlled,crossover trial

Our previous studies demonstrated that dietary supplementation with tea catechins combined with exercise improved endurance capacity in mice. This study aimed to demonstrate the effect of daily tea catechin consumption on aerobic capacity in humans. Sixteen Japanese non-athlete male subjects (aged 25–47 years) took 500 mL of a test beverage with or without tea catechins (570 mg) daily for 8 weeks and attended a training program twice a week. Aerobic capacity was evaluated by indirect calorimetry and near-infrared spectroscopy during graded cycle exercise. Catechin beverage consumption was associated with a significantly higher ventilation threshold during exercise and a higher recovery rate of oxygenated hemoglobin and myoglobin levels after graded cycle exercise when compared to subjects receiving the placebo beverage. These results indicate that daily consumption of tea catechins increases aerobic capacity when combined with semiweekly light exercise, which may be due to increased skeletal muscle aerobic capacity.     

Zopiclone versus placebo for short-term treatment of insomnia in patients with advanced cancer: study protocol for a double-blind,randomized, placebo-controlled,clinical multicenter trial

Background

Despite the high prevalence of insomnia in patients with advanced cancer, there are no randomized controlled trials on pharmacological interventions for insomnia in this group of patients. A variety of pharmacological agents is recommended to manage sleep disturbance for insomnia in the general population, but their efficacy and safety in adults with advanced cancer are not established. Thus, there is a need to evaluate the effectiveness of medications for insomnia in order to improve the evidence in patients with advanced cancer. One of the most used sleep medications at present in patients with cancer is zopiclone.

Methods

This is a randomized, double-blind, placebo-controlled, parallel-group, multicenter trial. A total of 100 patients with metastatic cancer who report insomnia will be randomly allocated to zopiclone or placebo. The treatment duration with zopiclone/placebo is 6 consecutive nights. The primary endpoint is patient-reported sleep quality during the final study night (night 6) assessed on a numerical rating scale of 0–10, where 0?=?Best sleep and 10?=?Worst possible sleep. Secondary endpoints include the mean patient-reported total sleep time and sleep onset latency during the final study night (night 6).

Discussion

Results from this study on treatment of insomnia in advanced cancer will contribute to clinical decision-making and improve the treatment of sleep disturbance in this patient cohort.

Trial registration

ClinicalTrials.gov, NCT02807922. Registered on 21 June 2016.

     

Maraviroc, a chemokine receptor-5 antagonist, fails to demonstrate efficacy in the treatment of patients with rheumatoid arthritis in a randomized, double-blind placebo-controlled trial

Introduction

The purpose of this study was to determine whether maraviroc, a human CC chemokine receptor 5 (CCR5) antagonist, is safe and effective in the treatment of active rheumatoid arthritis (RA) in patients on background methotrexate (MTX).

Methods

This phase IIa study comprised two distinct components: an open-label safety study of the pharmacokinetics (PK) of MTX in the presence of maraviroc, and a randomized, double-blind, placebo-controlled, proof-of-concept (POC) component. In the PK component, patients were randomized 1:1 to receive maraviroc 150 or 300 mg twice daily (BID) for four weeks. In the POC component, patients were randomized 2:1 to receive maraviroc 300 mg BID or placebo for 12 weeks. Patients were not eligible for inclusion in both components.

Results

Sixteen patients were treated in the safety/PK component. Maraviroc was well tolerated and there was no evidence of drug-drug interaction with MTX. One hundred ten patients were treated in the POC component. The study was terminated after the planned interim futility analysis due to lack of efficacy, at which time 59 patients (38 maraviroc; 21 placebo) had completed their week 12 visit. There was no significant difference in the number of ACR20 responders between the maraviroc (23.7%) and placebo (23.8%) groups (treatment difference -0.13%; 90% CI -20.45, 17.70; P = 0.504). The most common all-causality treatment-emergent adverse events in the maraviroc group were constipation (7.8%), nausea (5.2%), and fatigue (3.9%).

Conclusions

Maraviroc was generally well tolerated over 12 weeks; however, selective antagonism of CCR5 with maraviroc 300 mg BID failed to improve signs and symptoms in patients with active RA on background MTX.

Trial Registration

ClinicalTrials.gov: NCT00427934     

The efficacy of Liv-52 on liver cirrhotic patients: a randomized, double-blind, placebo-controlled first approach.

Cirrhosis is the irreversible sequel of various disorders that damage liver cells permanently over time. Presently, the use of herbal medicines for prevention and control of chronic liver diseases is in the focus of attention for both the physicians and the patients; the reasons for such shift toward the use of herbals include the expensive cost of conventional drugs, adverse drug reactions, and their inefficacy. In the present study, the efficacy of herbal medicine Liv-52 (consisting of Mandur basma, Tamarix gallica and herbal extracts of Capparis spinosa, Cichorium intybus, Solanum nigrum, Terminalia arjuna and Achillea millefolium) on liver cirrhosis outcomes was compared with the placebo for 6 months in 36 cirrhotic patients referred to Tehran Hepatic Center. The outcome measures included child-pugh score, ascites, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total billirubin, albumin, prothrombin time, platelet and white blood cells counts. The indices were recorded in all patients before and after 6 months of drug or placebo treatment. The results demonstrated that the patients treated with Liv-52 for 6 months had significantly better child-pugh score, decreased ascites, decreased serum ALT and AST. In placebo administered patients all the clinical parameters recorded at beginning of the study were not significantly different than after 6 months. We conclude that Liv-52 possess hepatoprotective effect in cirrhotic patients. This protective effect of Liv-52 can be attributed to the diuretic, anti-inflammatory, anti-oxidative, and immunomodulating properties of the component herbs.     

Efficacy of cinnamon patch treatment for alleviating symptoms of overactive bladder: A double-blind,randomized, placebo-controlled trial

BackgroundCurrent treatments for overactive bladder (OAB) have limited efficacy, low persistence and a high rate of adverse events commonly leading to treatment cessation in clinical practice. Clinicians in Asia commonly use traditional Chinese medicine as an alternative for OAB treatment despite it having uncertain efficacy and safety. To evaluate the efficacy and safety of cinnamon patch (CP) treatment for alleviating symptoms of OAB, a double-blind randomized, placebo-controlled trial was conducted in the present study.Materials and MethodsIn this 6-week randomized clinical trial conducted in an outpatient setting, 66 subjects diagnosed as having OAB were enrolled and treated with a placebo (n=33) or CP (n=33). The OAB symptom score (OABSS) was selected as the primary end point, and a patient perception of bladder condition (PPBC), an urgency severity scale (USS), and post-voiding residual urine (PVR) volume were selected as secondary end points. Statistical analyses were performed with IBM SPSS Statistics 20. Groups were compared using an independent sample t-test, Fisher exact test, and Chi-squared test.ResultsIn total, 66 participants (40 women and 26 men), 60.35 ± 12.77 years of age, were included in the intention-to-treat analyses. Baseline characteristics were comparable between the CP (n ==33) and placebo (n ==33) groups. Treatment with a CP showed statistically significant differences in reductions in OABSS scores (9.70 ± 2.20 to 6.33 ± 2.42), PPBC scores (3.36 ± 0.60 to 2.15 ± 0.83), and USS scores (2.67 ± 0.54 to 1.64 ± 0.60).ConclusionsCompared to a placebo, treatment with CP might be considered an effective and safe complementary therapy for OAB. Further studies employing a positive control, different dosage forms, larger sample sizes, and longer treatment periods are warranted.     

Effects of a flaxseed-derived lignan supplement in type 2 diabetic patients: a randomized, double-blind, cross-over trial

Background

Flaxseed consumption has been shown to improve blood lipids in humans and flaxseed-derived lignan has been shown to enhance glycemic control in animals. The study aimed to investigate the effect of a flaxseed-derived lignan supplement on glycemic control, lipid profiles and insulin sensitivity in type 2 diabetic patients.

Methodology/Principal Findings

This was a randomized, double-blind, placebo-controlled, cross-over trial and it was conducted between April and December 2006 in Shanghai, China. Seventy-three type 2 diabetic patients with mild hypercholesterolemia were enrolled into the study. Patients were randomized to supplementation with flaxseed-derived lignan capsules (360 mg lignan per day) or placebo for 12 weeks, separated by an 8-week wash-out period. HbA1c, lipid profiles, insulin resistance index and inflammatory factors were measured. Sixty-eight completed the study and were included in the analyses. The lignan supplement significantly improved glycemic control as measured by HbA_1c (-0.10±0.65 % vs. 0.09±0.52 %, P = 0.001) compared to placebo; however, no significant changes were observed in fasting glucose and insulin concentrations, insulin resistance and blood lipid profiles. Urinary excretion of lignan metabolites (enterodiol and enterolactone) was significantly higher after the lignan supplement intervention compared to baseline (14.2±18.1 vs. 1.2±2.4 µg/mL, P<0.001). Data also suggested minimal competition between lignan and isoflavones for bioavailability when measured by the excretion concentrations.

Conclusions/Significance

Daily lignan supplementation resulted in modest, yet statistically significant improvements in glycemic control in type 2 diabetic patients without apparently affecting fasting glucose, lipid profiles and insulin sensitivity. Further studies are needed to validate these findings and explore the efficacy of lignans on type 2 diabetes.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00363233","term_id":"NCT00363233"}}NCT00363233     

Smoked cannabis for spasticity in multiple sclerosis: a randomized, placebo-controlled trial

Background:

Spasticity is a common and poorly controlled symptom of multiple sclerosis. Our objective was to determine the short-term effect of smoked cannabis on this symptom.

Methods:

We conducted a placebo-controlled, crossover trial involving adult patients with multiple sclerosis and spasticity. We recruited participants from a regional clinic or by referral from specialists. We randomly assigned participants to either the intervention (smoked cannabis, once daily for three days) or control (identical placebo cigarettes, once daily for three days). Each participant was assessed daily before and after treatment. After a washout interval of 11 days, participants crossed over to the opposite group. Our primary outcome was change in spasticity as measured by patient score on the modified Ashworth scale. Our secondary outcomes included patients’ perception of pain (as measured using a visual analogue scale), a timed walk and changes in cognitive function (as measured by patient performance on the Paced Auditory Serial Addition Test), in addition to ratings of fatigue.

Results:

Thirty-seven participants were randomized at the start of the study, 30 of whom completed the trial. Treatment with smoked cannabis resulted in a reduction in patient scores on the modified Ashworth scale by an average of 2.74 points more than placebo (p < 0.0001). In addition, treatment reduced pain scores on a visual analogue scale by an average of 5.28 points more than placebo (p = 0.008). Scores for the timed walk did not differ significantly between treatment and placebo (p = 0.2). Scores on the Paced Auditory Serial Addition Test decreased by 8.67 points more with treatment than with placebo (p = 0.003). No serious adverse events occurred during the trial.

Interpretation:

Smoked cannabis was superior to placebo in symptom and pain reduction in participants with treatment-resistant spasticity. Future studies should examine whether different doses can result in similar beneficial effects with less cognitive impact.Spasticity is a common and disabling symptom that remains a substantial problem for many patients with multiple sclerosis. Some patients have adverse effects from conventional antispasticity medications; for others, spasticity persists despite treatment. A report from the Institute of Medicine in the United States concluded that the active compounds of cannabis (marijuana) are potentially effective in treating neurologic conditions and “should be tested rigorously in clinical trials.”¹ There is evidence that the cannabinoid receptors CB₁ and CB₂ may be involved in the control of spasticity in multiple sclerosis² and that the endogenous ligand of CB₁, anandamide, is itself an effective antispasticity agent.³ CB₁ receptors are primarily presynaptic; their activation inhibits calcium influx and glutamate release, and reduces neuronal excitability by activating somatic and dendritic potassium channels.⁴Although many patients with multiple sclerosis endorse smoking cannabis as therapy, evidence that it relieves spasticity is largely anecdotal, as most trials focus on orally administered cannabinoids. We sought to assess the safety and efficacy of smoked cannabis versus placebo in patients with multiple sclerosis who have treatment-resistant spasticity.