Long-term, real-world effectiveness of biologics for severe uncontrolled asthma: The PROSPECT study

Background: Several biologics (BIOs) are available to treat severe uncontrolled asthma. However, there are limited data regarding their long-term effectiveness in real-world clinical practice. We investigated the longterm, over 24 months, effectiveness of initiating a BIO in patients with severe uncontrolled asthma deemed candidates for BIO therapy. Methods: PROSPECT was a multicenter observational cohort study that enrolled patients with severe uncontrolled asthma in Japan. We divided the patients into two groups according to whether they did (BIO group) or did not (non-BIO group) initiate a BIO within 12 weeks of enrollment. The BIO (omalizumab, mepolizumab, benralizumab, and dupilumab) was chosen at the physician's discretion considering the patient's asthma phenotype. Results: Of 306 patients enrolled, 285 were included in the full analysis set (BIO group: n = 125; non-BIO group: n = 160). The adjusted least-squares mean change in post-bronchodilator forced expiratory volume in 1 s at 24 months was 0.17 L (95% confidence interval [CI]: 0.11 to 0.23) and 0.04 L (95% CI: -0.02 to 0.10) in the BIO and non-BIO groups, respectively (adjusted difference: 0.13 L; 95% CI: 0.04 to 0.21, P = 0.004). The changes from baseline to 6, 12, and 18 months were significantly greater in the BIO group. Reduction in asthma exacerbations, improvement in 5-item Asthma Control Questionnaire scores, decreased daily oral corticosteroid doses, and higher oral corticosteroid withdrawal rate were observed in the BIO group. Conclusions: Initiation of a BIO was associated with significant improvements in long-term lung function and asthma control among patients with severe uncontrolled asthma in real-world clinical practice. Trial registration: University Hospital Medical Information Network clinical trials registry (Japan), UMIN000038006. First registered: September 13, 2019.