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INTRODUCTION: Mixed treatment comparisons (MTCs) are increasingly important in the assessment of the benefit-risk profile of pharmaceutical treatments for relapsing-remitting multiple sclerosis (RRMS). Interpretation of MTCs requires a clear understanding of the methods of analysis and population studied. The objectives of this work were to compare MTCs of pharmaceutical treatments for RRMS, including a detailed description of differences in populations, treatments assessed, methods used and findings; and to discuss key considerations when conducting an MTC. METHODS: Fourteen databases were searched until July 2019 to identify MTCs (published during or after 2010) in adults (at least 18 years of age) with RRMS or rapidly evolving severe RRMS treated with any form of pharmaceutical treatment. No language restriction was imposed. RESULTS: Twenty-seven MTCs assessing 21 treatments were identified. Comparison highlighted many differences in conduct and reporting between MTCs relating to the patient populations or treatments included, duration of follow-up and outcomes of interest measured. The lack of similarity between the MTCs leads to questions about variability in the robustness of analyses and makes comparisons between studies challenging. CONCLUSION: Given the importance of MTCs for healthcare decision-making, it is imperative that reporting of methods, results and assumptions is clear and transparent to allow accurate interpretation of findings. For MTCs to be relevant, the choice of outcome measures should reflect clinical practice. Combination of treatments or of outcomes measured at different points of time should be avoided, as should imputation without justification. Furthermore, all approved treatment options should be included and updates of MTCs should be conducted when data for new treatments are published.
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OBJECTIVE: To evaluate efficacy, safety, and tolerability of laquinimod in patients with primary progressive multiple sclerosis (PPMS). METHODS: In the randomized, double-blind, placebo-controlled, phase 2 study, ARPEGGIO (A Randomized Placebo-controlled Trial Evaluating Laquinimod in PPMS, Gauging Gradations in MRI and Clinical Outcomes), eligible patients with PPMS were randomized 1:1:1 to receive once-daily oral laquinimod 0.6 mg or 1.5 mg or matching placebo. Percentage brain volume change (PBVC; primary endpoint) from baseline to week 48 was assessed by MRI. Secondary and exploratory endpoints included clinical and MRI measures. Efficacy endpoints were evaluated using a predefined, hierarchical statistical testing procedure. Safety was monitored throughout the study. The laquinimod 1.5 mg dose arm was discontinued on January 1, 2016, due to findings of cardiovascular events. RESULTS: A total of 374 patients were randomized to laquinimod 0.6 mg (n = 139) or 1.5 mg (n = 95) or placebo (n = 140). ARPEGGIO did not meet the primary endpoint of significant treatment effect with laquinimod 0.6 mg vs placebo on PBVC from baseline to week 48 (adjusted mean difference = 0.016%, p = 0.903). Laquinimod 0.6 mg reduced the number of new T2 brain lesions at week 48 (risk ratio 0.4; 95% confidence interval, 0.26-0.69; p = 0.001). Incidence of adverse events was higher among patients treated with laquinimod 0.6 mg (83%) vs laquinimod 1.5 mg (66%) and placebo (78%). CONCLUSIONS: Laquinimod 0.6 mg did not demonstrate a statistically significant effect on brain volume loss in PPMS at week 48. CLINICALTRIALSGOV IDENTIFIER: NCT02284568. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that, although well tolerated, laquinimod 0.6 mg did not demonstrate a significant treatment effect on PBVC in patients with PPMS.