Background: Multiple sclerosis is a presumed cell-mediated autoimmune disease of the central nervous system. Cyclophosphamide (CFX) is a cytotoxic and immunosuppressive agent, used in systemic autoimmune diseases. Controversial results have been reported on its efficacy in MS. We conducted a systematic review of all relevant trials, evaluating the CFX efficacy in patients with progressive MS.
Objectives: The main objectives were to determine whether CFX slows the disease progression.
Search strategy: Electronic databases (including MEDLINE, EMBASE, Cochrane Controlled Trials Register) were systematically searched. References list of retrieved studies and conference abstracts on the main meetings on Multiple Sclerosis were handsearched.
Selection criteria: Randomised controlled trials (RCTs) evaluating the clinical effect of CFX treatment in patients affected by clinically definite progressive MS. CFX had to be administered alone or in combination with ACTH or steroids. The comparison group had to be placebo or no treatment or the same co intervention (ACTH or steroids) The main outcome criteria were : progression of disability (defined as an increase of 0.5 point in Kurtzke Extended Disability Status Scale (EDSS) for patients with baseline EDSS > or = 6 and 1 for EDSS < or = 5.5), differences of disability between treatment-control groups and the number of patients with side effects.
Data collection and analysis: The identified references were reviewed by two reviewers who independently decided the eligibility of the study, extracted and summarized data and assessed the trial's quality. The statistical analysis was performed using the Cochrane RevMan software and analyzed using Cochrane MetaView.
Main results: Of the 326 identified references, 80 were selected for full review, only four RCTs were selected for the final analysis. Intensive immunosuppression with CFX (alone or associated with ACTH or prednisone) in patients with progressive MS compared to placebo or no-treatment (152 participants) did not prevent the long -term (12-18-24 months) risk to evolution to a next step of EDSS. However, the mean change in disability (final disability subtracted from the baseline) significantly favoured the treated group at 12 (effect size - 0.21; C. I. - 0.24, - 0.17) and 18 months (- 0.19; C. I. - 0.24, - 0.14). We were not able to verify the efficacy of other schedules. Five patients died; sepsis and amenorrhea frequently occurred in treated patients (descriptive analysis).
Reviewer's conclusions: Only limited objectives were reached. This review shows a role of CFX in the treatment of progressive MS, but less toxic schedules must be considered, before its use in the clinical practice.