OBJECTIVES:  To describe the clinical and economic burden of severe asthma patients over a 12-month period in France METHODS: Severe asthma patients, defined as patients with a continuous 12-month period of step-4 or 5 in the GINA classification, were identified in the COBRA cohort, an observational prospective cohort which has enrolled more than 1,000 patients from throughout France, since 2007. Medical and biological data were collected at baseline, every 6 months for the first 5 years, and annually for the following 5 years. The period of interest for the present study was the 12-month period following the continuous 12-month period of severe asthma. Data on clinical symptoms and healthcare resource utilization (HRU) were drawn from the COBRA database and from patients’ medical files. The clinical burden was described in terms of asthma exacerbations, symptoms outside exacerbations and level of control (ACT and ACQ-5). The economic burden was described in terms of HRU – including inpatient care, outpatient care, medication use and procedures – and related costs, taking a payer’s perspective. RESULTS: