Long-Term Therapy Response to Anti-IL-5 Biologics in Severe Asthma-A Real-Life Evaluation

BACKGROUND: Patients with severe eosinophilic asthma show different responses to various anti-IL-5 biologics, ranging from super response to nonresponse. Residual disease manifestations observed in partial responders may prompt physicians to switch between biologics. More data on response, switches, and residual disease manifestations are needed to improve personalized treatment.

OBJECTIVE: To assess (1) prevalences and predictors of super, partial, and nonresponders to long-term anti-IL-5 treatment, (2) frequency and reasons for switches between anti-IL-5 biologics, and (3) nature of residual disease manifestations.

METHODS: In this 2-year follow-up study, patients with severe asthma were included who initiated an anti-IL-5 biologic (mepolizumab, reslizumab, benralizumab) (n = 114). Patient characteristics (clinical, functional, inflammatory) and comorbidities were collected at baseline and 2-year follow-up. "Super responders" showed no residual disease manifestations at 2-year follow-up, "partial responders" experienced residual disease manifestations, and "nonresponders" discontinued anti-IL-5 treatment after less than 2 years because of clinical worsening.

RESULTS: After 2-year anti-IL-5 treatment, 14% of patients were super responders, 69% partial responders, and 11% nonresponders. Super response was predicted by shorter asthma duration and higher FEV1, and tended to be associated with adult-onset asthma, absence of nasal polyps, and lower body mass index. Switches between anti-IL-5 biologics occurred frequently (41%). After 2-year treatment, most common residual disease manifestations included impaired lung function (59%), uncontrolled sinonasal disease (58%), and uncontrolled asthma symptoms (48%).

CONCLUSIONS: After 2 years of anti-IL-5 treatment, a favorable response was found in 83% of patients with severe asthma, including a super response in 14%. Most partial responders show impaired lung function or uncontrolled sinonasal disease, causing physicians to switch between biologics.