Methods: Baseline values in adult patients (N=737) with allergic asthma who subsequently initiated treatment with omalizumab and had not received omalizumab within the preceding year were analyzed. Spearman correlation coefficients (rs) of biomarkers between one another and with FEV1 were determined.
Results: Mean baseline FEV1 was 74.7% of predicted value, n=728. Median and geometric mean baseline biomarker values were: FeNO, 22.0 and 23.6 ppb, n=722; EOS, 230 and 220/μL, n=662; and PERI, 48.3 and 48.9 ng/mL, n=660. Biomarkers were weakly correlated with one another at baseline. FeNO correlations were: EOS, rs=0.35 (95% CI 0.28, 0.41; p<0.0001; n=650); and PERI, rs=0.27 (95% CI 0.20, 0.34; p<0.0001; n=648). Correlation between EOS and PERI was rs=0.24 (95% CI 0.17, 0.31; p<0.0001; n=636). FEV1 was very weakly correlated with FeNO, rs=−0.10 (95% CI −0.17, −0.03; p=0.0079; n=716); EOS, rs=−0.12 (95% CI −0.19, −0.04; p=0.0028; n=659); and PERI, rs=−0.08 (95% CI −0.16, −0.01; p=0.0360, n=657).
Conclusions: This analysis provides information on the biomarker characteristics of allergic asthma patients before they initiated treatment with omalizumab in a real world setting. It also highlights the heterogeneity of biomarker profiles and the potential value of assessing more than a single biomarker of type 2 asthma status.