Disease

Spirometry: Baseline values can be found in Table 1. The mean values for the final FEV₁ measured in the ED (least squares means) were 2.12 L (64% predicted) with Z160, 2.09 L (62% predicted) with Z20, and 2.03 L (61% predicted) with placebo. Differences between Z160 and placebo were statistically significant at 90 min (p = 0.02), 210 min (p = 0.04), and at the end point (p = 0.02). Differences between Z20 and placebo did not reach statistical significance.

Dyspnea: From ED entry to just before randomization, median Borg values changed from 7 (mean, 6.68) to 5 (mean, 4.96). At 210 min, the final median Borg values were reduced to 1 (mean, 1.48) in the Z160 group, 2 (mean, 2.08) in the Z20 group, and 2 (mean, 2.02) in the placebo group. Compared with placebo, these differences were significant for Z160 (p = 0.005), but were not for Z20.

Outpatient Period Outcomes

Relapse: By the 28-day visit, 143 of 546 patients (26.2%) had relapsed (zafirlukast, 65 of 276 patients [23.6%]; placebo, 78 of 270 patients [28.9%]). Compared with placebo, treatment with zafirlukast reduced the absolute rate of relapse by 5.3%, which equates to a relative risk reduction of 18.3% (p = 0.047; hazards ratio, 0.714; 95% CI, 0.512 to 0.996). Figure 3 shows the Kaplan-Meier curves for the probability of time to relapse through the last dose of trial treatment Tretinoin cream Canada. When zafirlukast-treated patients were considered by the ED dose of zafirlukast, relapse rates were similar (patients treated with Z160/Z20 bid, 22.8%; patients treated with Z20/Z20 bid, 24.4%). Through the 14-day follow-up period, cumulative postrandomization relapse rates were 27% in the zafirlukast treatment group and 32% in the placebo treatment group

Table 2—Disease-Related History for Patients Who Entered the Outpatient Period