Clinical and economic burden of severe asthma among US patients treated with biologic therapies

BACKGROUND: Patients with severe asthma may remain uncontrolled despite biologic therapy in addition to standard therapy, but this disease burden has not been quantified. OBJECTIVE: To estimate the clinical and economic burden in a US national sample. METHODS: Patients who have severe asthma with indicated biologic treatment (earliest use = index date) were selected from the MarketScan database between January 1, 2013, and June 30, 2018. Inclusion criteria were continuous enrollment for 12 months postindex with a minimum of 2 biologic fills, greater than or equal to 12 years of age, evidence of medium- to high-dose inhaled corticosteroids and long-acting β-agonist combination before the index, and absence of other respiratory diagnoses and malignancies. Disease exacerbations (used to classify asthma control), health care costs, and treatment characteristics were reported during the 12-month postindex period. RESULTS: The sample included 3262 biologic patients; 88% with anti-immunoglobulin E therapy (omalizumab) and 12% non-anti-immunoglobulin E (reslizumab, mepolizumab, benralizumab). The mean age was 49 (±15) years; 64% were women. Prescriptions included inhaled corticosteroids and long-acting β-agonist (82%), systemic corticosteroids (76%), and leukotriene receptor antagonists (68%). Notably, 63% of patients presented greater than or equal to 1 asthma exacerbation (mean 1. 3 per patient/year). Furthermore, 35% of patients were categorized as having controlled asthma, whereas 28% were suboptimally controlled and 29% were uncontrolled. Patients with uncontrolled disease had higher all-cause and asthma-related costs (69, 206 and 45, 693, respectively) than patients with suboptimally controlled (59, 407 and 40, 793, respectively) or controlled disease (53, 083 and 38, 393, respectively). Furthermore, 62% of newly treated patients were persistent with their index biologic. CONCLUSION: Biologic therapies are effective in reducing exacerbations, but a substantial proportion of patients with severe asthma treated with current biologics continue to experience uncontrolled disease, highlighting a remaining unmet need for patients with severe uncontrolled asthma.