BACKGROUND: The development of novel targeted biologic therapies for severe asthma has provided an opportunity to consider remission as a new treatment goal.
RESEARCH QUESTION: How many severe asthma patients treated with biologic therapy achieve clinical remission, and what predicts response to treatment?
STUDY DESIGN AND METHODS: The Danish Severe Asthma Registry is a nationwide register including all adult patients receiving biologic therapy for severe asthma in Denmark. We conducted an observational cohort study and defined "clinical response" to treatment after 12 months as ≥50% reduction in exacerbations, and/or a ≥50% reduction in maintenance oral corticosteroid dose, if required. "Clinical remission" was defined by cessation of exacerbations and maintenance OCS, as well as a normalization of lung function (FEV1%>80%) and an Asthma Control Questionnaire-6 score ≤1.50 after 12 months of treatment.
RESULTS: After 12 months of treatment of 501 biologically naïve patients, there were 104 (21%) patients with no response to treatment, whereas 397 (79%) had a clinical response. Among the latter, 97 (24%) fulfilled our criteria of clinical remission, corresponding to 19% in the entire population. Remission was predicted by shorter duration of disease and lower BMI in our entire population of all patients treated with biologic therapy.
INTERPRETATION: Clinical response was achieved in most adult patients initiating biologic therapy and clinical remission was observed in 19% of the patients after 12 months of treatment. Further studies are required to assess the long-term outcome of achieving clinical remission on biologic therapy.