Long-Term Effectiveness Of Omalizumab Treatment In Thai Severe Asthmatic Patients: A Real-Life Experience

To evaluate the long-term effectiveness of omalizumab in ‘real-life’ setting among Thai asthmatic patients. A multi-center, non-interventional, observational study in severe allergic asthma patients who received omalizumab treatment in 10 centers over Thailand (average duration 13.2 months with range 16 weeks-2 years). Outcomes included level of asthma control (ACT score), exacerbation rate, hospitalization rate, ER visit rate, and daily ICS dose. 61 patients were reviewed. ACT score increased from 13.8 baseline to 16.4 at Week 16 (p=0.201) and increased to 20.6 at Week 52 (p=0.005). The proportion of patients with controlled asthma (ACT score >20) increased from 17% baseline to 52.8% and 72.2% at Week 16 and 52, respectively. The mean annualized rate of asthma exacerbations was reduced at Week 16 and Week 52, (p<0.05), respectively. The mean hospitalization rate was reduced from 0.56 in previous year to 0.20 at Week 16 and 0.25 at Week 52. A reduction in ER visits was observed at Week 16 and Week 52 (p<0.05), respectively. The mean daily dose of ICS equivalent to fluticasone was reduced slightly from baseline 652.46 mcg to 579.31 mcg at Week 52. In all, 78.7% patients continued omalizumab treatment for at least 1 year. Of the 9 patients who discontinued omalizumab, 55.5% had relapse within 3 months and needed to restart treatment. This data confirms the effectiveness of omalizumab in Thai severe asthmatic patients but also confirms a high relapse rate in Thai patients who received omalizumab for 2 years or less.