Bergenstal RM, Nimri R, Beck RW, et al. - In this multinational, randomised, crossover trial (Fuzzy Logic Automated Insulin Regulation [FLAIR]),researchers sought to compare outcomes using a commercially available hybrid closed-loop system vs a new investigational system with features potentially useful for adolescents and young adults with type 1 diabetes. People aged 14–29 years old, with a clinical diagnosis of type 1 diabetes with a duration of at least 1 year, using either an insulin pump or multiple daily insulin injections, and glycated haemoglobin levels of 7·0–11·0% (53–97 mmol/mol) were selected from seven academic-based endocrinology practices, four in the USA, and one each in Germany, Israel, and Slovenia.One hundred thirteen people were recruited into the trial between June 3 and Aug 22, 2019. In adolescents and young adults with type 1 diabetes, hyperglycaemia was decreased without raising hypoglycaemia by using the investigational advanced hybrid closed-loop system compared with the commercially available MiniMed 670G system. The successful use of this technology will be improved by testing an advanced hybrid closed-loop device in communities that are underserved due to socioeconomic factors and testing during pregnancy and in people with impaired hypoglycaemia knowledge.