Bronchial Thermoplasty in Severe Asthma With Frequent Exacerbations

Inclusion criteria: * Age 18-65 years * Asthma which requires treatment with guidelines suggested medications for GINA steps 4-5 * Four or more bursts of systemic corticosteroids \>3 days each in the previous year * Willingness and ability to give written informed consent Exclusion criteria: * Current smoker and former smoker \> 10 pack years total smoking history * Participation in another clinical trial within the prior 4 months * Omalizumab therapy within the prior 4 months * Allergic bronchopulmonary aspergillosis * Patient having had severe exacerbation of their asthma requiring high doses of oral corticosteroids (\> 60 mg equivalent prednisolone) more than one month in the previous year * Post-bronchodilator FEV1 of less than 30% * Past diagnosis of COPD and chronic respiratory insufficiency * Known coagulopathy or platelet dysfunction * Use of anticoagulants * Use of an internal or external pacemaker or internal cardiac defibrillator * Contraindication to perform bronchoscopy * Contraindication to perform general anesthesia * Significant cardiovascular disease * Current or recent respiratory tract infection resolved less than 4 weeks * Known cancer or cancer history less than 12 months * Pregnancy and nursing mother