Results of a 12-week double blind clinical trial which randomized patients to placebo (PLA), salmeterol50mcg (SAL), fluticasone propionate 1OOmcg (FP), or salmeterol 50mcg/fluticasone propionate 1OOmcg combination (SFC) administered via Diskus were analysed post-hoc to determine if the response to treatment was dependent on the type of inhaled corticosteroid used at baseline. The overall study results have been previously reported (Edwards, Am J Resp Crit Care Med 1998; l57(3); A-414). A subset of patients who entered this trial were required to be treated with daily doses of either 336-420mcg belcomethasone dipropionate (BDP), 800-IOOOmcg triamcinolone acetonide (TAA), IOOOmcg flunisolide (FLN) or 176mcg FP for one month prior to entering the study and discontinuing use at randomization. Subsets of patients were defined by type of inhaled corticosteroid used at baseline. Patients treated with FP and FLN at baseline were combined in a single category (Other) because of small numbers. Eligible patients also demonstrated evidence of airway obstruction (40- 85% predicted FEV, and a 15% reversibility following 2 puffs of Ventolin). Efficacy variables examined for these subsets included percent of patients withdrawn due to worsening asthma and percent change in morning pre-dose FBV, at endpoint. Demographics and baseline lung function between patients using BDP, TAA and Other cotticosteroids were similar. At baseline, the ranges of percent predicted FEV, across the treatment groups was 68-70% for patients using BDP compared with 63-65% for patients using TAA at baseline and 62-69% for those patients using Other corticosteroids at baseline. Patients who received SFC had fewer withdrawals due to worsening asthma and greater improvements in lung function than FP, SAL, or PLA, regardless of baseline inhaled corticosteroid therapy.
