Insulin deficiency and impaired glucose homeostasis are hallmarks of type 1 diabetes. Since the discovery of insulin, pharmacological and clinical developments have endeavoured to replicate its endogenous pharmacokinetics (PK) and pharmacodynamics (PD). Closed loop insulin delivery systems operate as an artificial pancreas by making automated insulin dose adjustments based on real time continuous glucose monitoring. The increasing adoption of continuous insulin pump therapy and evolving technological advances have seen significant progress in the development of closed loop insulin delivery systems. This article reviews the current landscape of closed loop insulin delivery systems and pharmacological advances that could overcome current barriers.