Efficacy and Safety of Natalizumab for Multiple Sclerosis and Crohn's Disease: A Meta Analysis

OBJECTIVE:To systematically evaluate the safety and efficacy of natalizumab in treating multiple sclerosis (MS) and Crohn's disease(CD). METHODS:Literatures from 1998 to 2009 were searched in databases including MEDLINE,EMBASE,The Cochrane Library, and CBM for randomized controlled trials (RCTs) and quasi-randomization controlled trials. Quality assessment and data extraction were conducted using the Cochrane Collaboration's RevMan 5.0 software and then a Meta analysis was performed. The main indicators included the rate of adverse reactions, the rate of serious adverse reactions,response rate,and remission rate. RESULTS:Thirteen trials entered the final analysis. The main findings in the MS trials included: the rate of serious and general adverse effects were no significantly different among different groups (P>0.05). The new lesions rate was not significantly different within 3 months after treatment [RR=0.99, 95%CI (0.82, 1.18), P=0.87], but was significantly lower in 6 months in the treatment group [RR=0.45, 95%CI (0.33, 0.60), P<0.00001], and such advantage was maintained till 2 years later [RR=0.49, 95%CI (0.45, 0.53), P<0.00001]. The 2-year relapse rate was also significantly lower in the treatment group [RR=0.51, 95%CI (0.38, 0.69), P<0.0001]. The main findings in CD trials were as follows: The incidences between serious reactions and general adverse reactions were not significantly different (P>0.05). The remission rate was not significantly different between treatment group and control group in the 2nd week [RR=4.67, 95%CI (0.65, 33.26), P=0.12], but became significantly higher in the treatment group after 12 weeks [RR=1.46, 95%CI (1.26, 1.70), P<0.00001]. The response rate was significantly higher in the treatment group [RR=1.53, 95%CI (1.15, 2.03), P=0.004]. CONCLUSIONS:The rates of serious and general adverse reactions are not remarkably increased after natalizumab treatment for both MS and CD. The new lesions rate and 2-year relapse rate of MS as well as the response rate and remission rate of CD are all improved after natalizumab treatment,especially after long-term administration. Although severe adverse effect such as progressive multifocal leukoencephalopathy may occur,its clinical application can be further promoted after cautiously balancing the benefits and risks.