Systematic Review on the Efficacy of Fexofenadine in Seasonal Allergic Rhinitis: A Meta-Analysis of Randomized, Double-Blind, Placebo-Controlled Clinical Trials

Rationale: Evidence-based medicine represents the effort to highlight the best intervention for patients, clinicians, and policy makers, each from their respective viewpoint, to solve a particular health condition. According to a recently diffused grading system of evidence and recommendations for medical interventions, efficacy and safety represent 2 of the most important features to consider, and data from metaanalyses of randomized controlled clinical trials (RCTs) is the strongest supporting demonstration. Fexofenadine has been used for its efficacy and safety in the treatment of allergic rhinitis (AR) for many years although no meta-analyses supporting its use currently exist. The aim of this study is to assess for the first time the efficacy and safety of fexofenadine in the treatment of AR by means of a meta-analytic analysis of existing RCTs. Since specific evidence should be provided to address recommendations in a pediatric population, the quality of the estimates of this subgroup analysis is assessed. Methods: All double-blind, placebo-controlled randomized trials assessing the efficacy of fexofenadine inAR were searched for in OVID, Medline, and Embase databases up to December 2007. Outcomes were extracted from original articles; when this information was not available, the authors of each trial were contacted. Some graphics were digitalized. The RevMan 5 program was used to perform the analysis. GradePro 3.2.2 was used to assess the quality of the evidence for a pediatric population. Results: Of 2,152 identified articles, 20 were potentially relevant trials. Eight studies satisfied the inclusion criteria and were included in the meta-analysis. The main reasons for exclusion were: unnatural exposure, strong study limitations, an atypical outcome measurement, a design for other outcomes, and not being a placebo-controlled, single-blind study. Seven trials investigated a mixed population of adults and children, 1 trial investigated only children, and 1 trial only adults. In 1,833 patients receiving fexofenadine (1,699 placebo), a significant reduction of the daily reflective total symptom scores (TSS) (SMD –0.42; 95% CI –0.49 to –0.35, p ! 0.00001) was found. Positive results were also found for morning instantaneous