The CHRONICLE Study is a multi-center, non-interventional, prospective cohort study of adults with severe asthma who do not achieve control with high-dose inhaled corticosteroid (ICS) therapy with additional controllers and/or require systemic corticosteroid or monoclonal antibody therapy. Data will be collected from the healthcare provider in a uniform manner for every patient enrolled using an electronic case report form (eCRF). Data will be collected monthly from patients via web-based surveys. Patients will be followed until study discontinuation or the patient withdraws from the study or death, whichever occurs first. The expectation is that patients will be followed for a period of at least 3 years.