Objectives: Only one-third of patients with severe asthma (SA) achieve a complete response to biologics. This study aims to characterize two types of failure: early (EF), occurring ≤ 12 months after biologic initiation, and late (LF), occurring at any time during follow-up after response has been achieved at 12 months.
Methods: This is a multicentre retrospective study of adults treated with the same biologic for ≥24 months. Response was defined as no severe exacerbations in the preceding 12 months, Asthma Control Test ≥20, and no need for maintenance oral corticosteroids. Failure (EF or LF) was defined as non-achievement of any of these objectives.
Results: Two hundred and seventy-two patients were analysed with a mean follow-up of 46.1 ± 19.4 months. At 12 months, 97/272 were classified as PF, but 40% of them recovered response on subsequent visits (by changing inhaled therapy in 74%). Among the 175 responders at 12 months, 124 (70.8%) maintained response throughout the study period, while 51 (29.1%) experienced SF; those patients had lower FEV1 values after 12 months of biological therapy. SF reverted in 36% of cases, with inhaled therapy changes in 41.6%. FEV1 decreased by ≥100 mL in 12 of 16 cases who did not recover response after SF.
Conclusion: Most patients who achieve response at 12 months maintain it over time, but 29% of them suffer LF. Optimization of inhaled therapy can aid response recovery from EF or LF. Maximizing pulmonary function helps to prevent loss of response.
