Impact of body mass index on omalizumab response in adults with moderate-to-severe allergic asthma.

BACKGROUND: Effectiveness of asthma treatment, including biologics, may be different in patients with higher body mass index (BMI). OBJECTIVE: To evaluate response to omalizumab (dosed by serum immunoglobulin E level and weight) by BMI category. METHODS: Pooled data from 2 randomized, double-blind, placebo-controlled studies of adults with moderate-to-severe allergic asthma were analyzed by BMI category (<25 kg/m2 [normal or underweight], n = 397; 25 to <30 kg/m2 [overweight], n = 330; ≥ 30 kg/m2 [obese], n = 268). Placebo-adjusted exacerbation rate reductions were evaluated by Poisson regression modeling. Changes from baseline in forced expiratory volume in 1 second, beclomethasone dipropionate (BDP) dose, Total Asthma Symptom Score, and Asthma Quality of Life Questionnaire were evaluated by analysis of covariance. RESULTS: Greater placebo-adjusted exacerbation rate reductions (95% confidence interval) were observed with increasing BMI (normal or underweight, -37.4% [-69.0% to 26.8%]; overweight, -52.7% [-78.4% to 3.7%]; obese, -71.9% [-86.9% to -39.5%]). There were no differences in forced expiratory volume in 1 second improvement between BMI categories at week 16 (normal or underweight, 76.2 [5.3-147.1] mL; overweight, 98.1 [13.9-182.4] mL; obese, 69.1 [-18.9 to 157.2] mL). No differences in BDP dose reduction (µg) were noted between BMI categories (normal or underweight, 23.0 [15.7-30.3]; overweight, 22.5 [13.5-31.5]; obese, 16.6 [5.8-27.3]). Fewer patients in the higher BMI categories eliminated BDP use. There were trends for smaller improvements with higher BMI in Total Asthma Symptom Score (normal/underweight, -0.52 [-0.82 to -0.22]; overweight, -0.50 [-0.80 to -0.20]; obese, -0.39 [-0.77 to 0.00]) and Asthma Quality of Life Questionnaire (normal or underweight, 0.34 [0.16-0.52]; overweight, 0.34 [0.13-0.55]; obese, 0.15 [-0.08 to 0.39]). CONCLUSION: Omalizumab provides benefit to patients with moderate-to-severe allergic asthma, regardless of BMI. TRIAL REGISTRATION: Studies 008/009 were conducted before clinical trial registration was required, and therefore clinical trial registration numbers are not available.

Response to Omalizumab in Black and White Patients with Allergic Asthma.

BACKGROUND: Higher asthma burden is more likely to be experienced by Black than White patients. In clinical research, underrepresentation of minority populations is observed. OBJECTIVE: To estimate response to omalizumab in Black and White patients in North America with moderate to severe asthma. METHODS: Data from placebo-controlled (EXTRA) and single-armed (PROSPERO) omalizumab studies were used for this post hoc analysis. We used a Poisson regression model to examine exacerbation rates. An analysis of covariance model was used to estimate placebo-corrected change in FEV1 and Asthma Quality of Life Questionnaire (AQLQ) by racial group. RESULTS: This analysis included 631 White and 176 Black patients from EXTRA and 567 White and 130 Black patients from PROSPERO. In EXTRA, placebo-corrected exacerbation rate reductions (relative rate change [95% confidence interval], 22.6% [2.0-38.9%] vs 22.0% [-18.0% to 48.4%]) and FEV1 improvements were similar for White and Black patients. There was a trend toward greater AQLQ improvements for Black versus White patients (least squares mean treatment differences: 0.0 vs 0.3, 0.6 vs 0.4, and 0.6 vs 0.2 at weeks 16, 32, and 48, respectively) throughout the study. In PROSPERO, on-study exacerbation rates (0.76 [0.65-0.88] vs 0.77 [0.56-1.10]) and AQLQ improvements (least squares mean change from baseline: 1.2 vs 1.2 and 1.3 vs 1.2 at month 6 and end of study, respectively) were similar for White versus Black patients. A trend toward greater FEV1 improvement was observed in White versus Black patients throughout the study. CONCLUSIONS: This analysis of EXTRA and PROSPERO suggests that Black and White patients with moderate to severe asthma experience similar improvements in exacerbations, FEV1, and AQLQ with omalizumab.