A systematic review of 24 real-world observational studies in adult patients with severe allergic asthma (SAA) has confirmed the short- and long-term efficacy of omalizumab in improving lung function, asthma symptoms, and quality of life, while reducing co-medication, severe exacerbations, school/workdays lost, and healthcare resource utilization (HCRU)—with benefits extending up to 2-4 years after therapy. Furthermore, a previous meta-analysis conducted on these noncontrolled studies demonstrated the real-life pharmacotherapeutic effectiveness of omalizumab and complemented the efficacy data from randomized controlled trials (RCTs). More recently, a systematic review of 42 real-world studies of omalizumab in patients for more than 12 years confirmed the long-term effectiveness beyond 4 years.
However, to date, no meta-analysis has summarized the real-world effectiveness of omalizumab in patients for 6 or more years in terms of global evaluation of treatment effectiveness (GETE), lung function, asthma exacerbations, oral corticosteroid (OCS) use, patient-reported outcomes (PROs), HCRU, and school/work absenteeism. To address this knowledge gap, researchers conducted a meta-analysis to assess the efficacy of omalizumab based on these outcome measures in patients with SAA, in a study published in The Journal of Allergy and Clinical Immunology: In Practice. Observational studies in patients with severe allergic asthma (≥6 years) treated with omalizumab for 16 or more weeks, published from January 2005 to October 2018, were reviewed. A random-effects model was used to assess heterogeneity. In total, 86 publications were included.
GETE Found to Be Good/Excellent in 77% of Patients
The study investigators found that GETE was good/excellent in 77% of patients at 16 weeks (risk difference, 0.77; 95% CI, 0.70-0.84; I2, 96%) and in 82% patients at 12 months (risk difference, 0.82; 95% CI, 0.73-0.91; I2, 97%). The mean improvements in FEV1 were 160, 220, and 250 mL at 16 weeks, 6 months, and 12 months, respectively. There were decreases in Asthma Control Questionnaire scores at 16 weeks (-1.14), 6 months (-1.56), and 12 months (-1.13) with omalizumab therapy. The study team observed that omalizumab significantly reduced annualized rate of severe exacerbations (risk ratio [RR], 0.41; 95% CI, 0.30-0.56; I2, 96%), proportion of patients receiving OCS (RR: 0.59; 95% CI, 0.47-0.75; I2, 96%), and number of unscheduled physician visits (mean difference: -2.34; 95% CI, -3.54 to -1.13; I2, 98%) at 12 months versus baseline.
“The consistent improvements in GETE, lung function, and PROs, and reductions in asthma exacerbations, OCS use, and HCRU with add-on omalizumab in real-life confirm, complement, and extend the efficacy findings observed in RCTs in patients with SAA,” the study authors wrote.