PurposeOmalizumab was first approved in China in 2017 for the treatment of moderate to severe allergic asthma for adult and adolescent patients aged ≥12 years. In accordance with the Chinese Health Authority requirement, the post-authorization safety study (PASS) was conducted to evaluate the safety and effectiveness of omalizumab in a real-world setting in patients with moderate to severe allergic asthma in China over a 24-week observation period.Patients and MethodsThis is a single-arm, non-interventional, multicenter, PASS conducted in adult, adolescent, and pediatric patients (≥6 years old) with moderate to severe allergic asthma receiving omalizumab in a real-world clinical setting from 2020 to 2021 in 59 sites of mainland China.ResultsIn total, 1546 patients were screened and 1528 were enrolled. They were stratified according to age (6 to <12 years [n = 191]; ≥12 years [n = 1336]; unknown [n = 1]). Among the overall population, 23.6% and 4.5% of patients reported adverse events (AEs) and serious adverse events (SAEs), respectively. Among pediatric patients (6 to <12 years), 14.1% and 1.6% patients reported AEs and SAEs, respectively. AEs that led to treatment discontinuation in both age groups were <2%. No new safety signals were reported. Effectiveness results showed improvement in lung function, asthma control, and quality of life (QoL).ConclusionThe findings of the current study demonstrated that the safety profile of omalizumab was consistent with its known profile in allergic asthma, and no new safety signals were reported. Omalizumab treatment was effective in improving the lung function and QoL in patients with allergic asthma.