PurposeOmalizumab is the preferred add-on therapy for patients with moderate-to-severe persistent allergic asthma and has demonstrated efficacy and safety in various ethnicities. This study evaluated the efficacy and safety of omalizumab in Chinese patients with moderate-to-severe allergic asthma.MethodsThis randomized, double-blind, parallel-group, placebo-controlled, phase III study assessed lung function, quality of life, asthma control, and safety of omalizumab after 24-week therapy in Chinese patients (18-75 years of age).ResultsA total of 616 patients were randomized (1:1) to omalizumab or placebo. The primary endpoint, least squares mean treatment difference (LSM-TD) in morning peak expiratory flow (PEF) (omalizumab vs placebo), at Weeks >20-24 was 8.85 L/min (Full analysis set; P=0.062). Per-protocol analysis set showed significant improvements with LSM-TD of 11.53 L/min in mean mPEF at Weeks >20-24 (P=0.022). The FEV1 % predicted was significantly improved with omalizumab vs placebo from 8 to 24 weeks (after 24-week treatment: LSM-TD=4.12%; P=0.001). At Week 24, a higher proportion of omalizumab-treated patients achieved clinically relevant improvements in standardized AQLQ (58.2% vs 39.3%; LSM=0.51 vs 0.10; P<0.001) and ACQ (49.5% vs 35.5%; LSM=-0.51 vs -0.34; P=0.002) scores vs placebo. Total and nighttime symptom scores reduced significantly with omalizumab vs placebo (LSM-TD=-0.21, P=0.048 and -0.12, P=0.011, respectively). Although the study was not powered to study differences in exacerbation rates (P=0.097), exacerbations in winter months were less frequent in the omalizumab vs placebo group (2 vs 21). Adverse event and severe adverse event rates were comparable between omalizumab and placebo.ConclusionsOmalizumab improves lung function, quality of life, and asthma control in Chinese patients with moderate-to-severe persistent allergic asthma and has a good safety profile.