INS and type 1 diabetes mellitus: In this multinational, multicentre, open-label, randomised trial, we show that 12-week use of a day-and-night hybrid closed-loop insulin delivery system, compared with sensor-augmented insulin pump therapy, was associated with an improvement in overall glucose control and a reduction in hypoglycaemia risk in suboptimally controlled type 1 diabetes in children, adolescents, and adults.