An automated closed-loop blood glucose control system for the controlled delivery of insulin to a patient comprising: a continuous glucose-monitoring sensor configured to provide a plurality of glucose measurement values representative of a measured glucose level of the patient at an associated plurality of measurement times; a subcutaneous insulin delivery device configured to deliver exogenous insulin in a subcutaneous tissue of the patient in response to an insulin delivery control signal, in particular continuously infused insulin and/or bolus insulin; and a controller programmed to receive the glucose measurement values and provide the delivery control signal to the insulin delivery device, wherein the controller is able to determine the insulin delivery control signal on the basis of a predicted glucose level determined by computing a physiological model of glucose-insulin system in the patient, said model describing the effect of insulin in the patient's body and its impact on the patient's glucose level and comprising a system of differential equations describing the evolution of a plurality of state variables (D1, D2, S1, S2, Q1, Q2, x1, x2, x3, I) as a function of time, said variables containing at least an instantaneous on-board insulin level representative of a quantity of insulin present in the subcutaneous layer and an instantaneous plasma insulin level representative of a quantity of insulin in a plasma of the patient, wherein said physiological model includes a sub-model of subcutaneous insulin absorption kinetics modeling transport of insulin from the subcutaneous tissue to the plasma, said sub-model comprising at least one differential equation describing an absorption of insulin from the subcutaneous tissue to the plasma characterized in that the instantaneous absorption rate of insulin from the subcutaneous tissue to the plasma is a decreasing function of the instantaneous on-board insulin level. a continuous glucose-monitoring sensor configured to provide a plurality of glucose measurement values representative of a measured glucose level of the patient at an associated plurality of measurement times; a subcutaneous insulin delivery device configured to deliver exogenous insulin in a subcutaneous tissue of the patient in response to an insulin delivery control signal, in particular continuously infused insulin and/or bolus insulin; and a controller programmed to receive the glucose measurement values and provide the delivery control signal to the insulin delivery device, wherein the controller is able to determine the insulin delivery control signal on the basis of a predicted glucose level determined by computing a physiological model of glucose-insulin system in the patient, said model describing the effect of insulin in the patient's body and its impact on the patient's glucose level and comprising a system of differential equations describing the evolution of a plurality of state variables (D1, D2, S1, S2, Q1, Q2, x1, x2, x3, I) as a function of time, said variables containing at least an instantaneous on-board insulin level representative of a quantity of insulin present in the subcutaneous layer and an instantaneous plasma insulin level representative of a quantity of insulin in a plasma of the patient, wherein said physiological model includes a sub-model of subcutaneous insulin absorption kinetics modeling transport of insulin from the subcutaneous tissue to the plasma, said sub-model comprising at least one differential equation describing an absorption of insulin from the subcutaneous tissue to the plasma characterized in that the instantaneous absorption rate of insulin from the subcutaneous tissue to the plasma is a decreasing function of the instantaneous on-board insulin level.