Nabiximols in Chronic Neuropathic Pain: A Meta-Analysis of Randomized Placebo-Controlled Trials.

OBJECTIVE: Pooled analysis of nabiximols and placebo in randomized controlled studies (RCTs) of chronic neuropathic pain. DESIGN: Systematic review and meta-analysis. METHODS: A systematic literature search was conducted to identify double-blind placebo-controlled RCTs of nabiximols for chronic neuropathic pain. The clinical endpoint of interest was change from baseline in mean pain score on 11-point numerical rating scales. Mean difference (MD) and standardized mean difference (SMD, Hedges' g) were calculated using fixed effect (FE) and random effects (RE) models. Strength of evidence was assessed using the Cochrane Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. Risk of bias was assessed using the revised Cochrane risk-of-bias tool (RoB 2). RESULTS: Nine RCTs with 1289 participants were included. Quality of evidence (GRADE) was moderate. One study had a high risk of bias (RoB 2) and five had some concerns. For the pooled endpoint of change from baseline in mean pain score, nabiximols was superior to placebo, with a MD of -0.40 (95% confidence interval [CI]: -.59 to -.21; FE, P < .0001) or -0.44 (95% CI: -.70 to -.19; RE, P = .0006). A SMD of -0.21 (95% CI: -.32 to -.10; FE) or -0.26 (95% CI: -.42 to -.10; RE) indicated an incremental benefit over background analgesia. Results in favor of nabiximols were maintained in sensitivity analyses. CONCLUSIONS: Nabiximols was superior to placebo for reduction of chronic neuropathic pain, with a small effect size. Larger RCTs designed to assess the effect of nabiximols in neuropathic pain are required to reach more definitive conclusions.

Quality Assessment in Multiple Sclerosis Therapy (QUASIMS): a comparison of interferon beta therapies for relapsing-remitting multiple sclerosis.

Interferon beta (IFN beta) preparations are the most frequently prescribed therapies for patients with relapsing multiple sclerosis (MS). Several open-label observational studies report similar efficacy among IFN beta preparations. The Quality Assessment in Multiple Sclerosis Therapy (QUASIMS) study is a large, open-label observational study designed to compare the effectiveness and tolerability of available IFN beta preparations as disease-modifying therapies for relapsing MS across a wide range of clinical practice settings. This retrospective, controlled cohort study was conducted by chart review at 510 sites in Germany, Austria, and Switzerland. Enrolled patients had received one of the four available IFN beta preparations/dosing regimens (intramuscular IFN beta-1a 30 microg 1x/week [Avonex], subcutaneous (SC) IFN beta-1a 22 or 44 microg 3 x/week [Rebif], or SC IFN beta-1b 250 microg 3.5x/week [Betaferon/Betaseron]) for >or= 2 years. Pre-planned outcomes at 1 and 2 years included change from baseline Expanded Disability Status Scale (EDSS) score, percentage of progression-free patients (< 1.0 EDSS point), annualised relapse rate (RR), percentage of relapse-free patients, and reasons for therapy change. Of 4754 evaluable patients, 3991 (84%) received IFN beta as initial therapy. There were no significant differences among IFN betas when used as initial or follow-up therapy on almost all outcome variables. Relapse rate was consistently higher and percentage of relapse-free patients consistently lower for all products used as follow-up versus initial therapy. Results of QUASIMS showed similar effectiveness among IFN beta products. Benefits were consistently superior when IFN beta was used as initial rather than follow-up therapy. Our results suggest that patients do not benefit in terms of disease outcome from switching between IFN beta preparations/dosing regimens.