Association between consistent omalizumab treatment and asthma control.

BACKGROUND: Omalizumab is indicated for patients with moderate-to-severe allergic asthma with inadequately controlled symptoms.
OBJECTIVE: We evaluated the association between consistent omalizumab treatment and asthma control.
METHODS: Health insurance claims from the MarketScan database (2002Q1-2011Q2) were analyzed. Asthmatic patients with ≥12 months of continuous insurance coverage after the first omalizumab claim (index date) after 6 months of continuous omalizumab use were included. A 12-month landmark period was used to assess treatment consistency, defined as uninterrupted treatment without a gap of ≥28 days in omalizumab use. The effect of consistent omalizumab treatment on asthma control between months 13 and 24 was evaluated. Multivariate time-varying Cox regressions were also conducted to assess the adjusted effect of treatment interruption on asthma control from month 1 to month 24.
RESULTS: A total of 3044 patients (mean age, 48.5 years; female, 62%) formed the study population. Patients consistent with omalizumab treatment at 12 months (39% of patients) were less likely to have an uncontrolled asthma event during months 13 to 24 with only 49% of patients experiencing one event compared with 54% in the non consistent subgroup (P = .02). In addition, consistent omalizumab treatment at 12 months was associated with a 51% reduction in the mean number of asthma-related emergency department (ED) visits per patient and a 28% reduction in asthma-related hospitalizations. Multivariate analyses corroborated these findings (hazard ratio for consistent vs non-consistent: risk of short-acting β2-agonists prescription, oral corticosteroids prescription, ED visit, or hospitalization, 0.76; 95% CI, 0.69-0.83]).
CONCLUSION: This analysis showed that consistent omalizumab treatment was associated with significant reductions in ED visits and hospitalizations.