Patent ID: 8715268

Claim:
An administration device for subcutaneous administration of a liquid drug to tissue of a patient over an extended period of time, the administration device comprising: an administration unit, the administration unit comprising a drug reservoir and a pump unit; a housing, the housing comprising the administration unit and being adapted to be carried by a patient over an extended period of time; a cannula; and a controller unit, the controller unit comprising a bolus administration profile controller, wherein: the bolus administration profile controller receives a bolus volume of a bolus to be administered; and determines based, at least in part, on the received bolus volume a bolus administration profile such that a depot volume of a depot is limited, said depot being a locally concentrated drug cloud in the subcutaneous tissue around the cannula, wherein the depot is a subcutaneous drug depot that is present during and shortly after the administration until the drug is absorbed by the tissue; wherein the administration device is configured for the subcutaneous administration of the liquid drug; and wherein the controller unit is configured to implement a code for the bolus administration based on an absorption model for the subcutaneous administration to determine a resulting depot volume of the bolus by accounting for a steady absorption bolus volume, a maximum steady absorption rate, and an administration time when the depot is empty at the beginning of the administration and when the depot is not empty, as a function of a time of zero at a beginning of administration to an administration time; wherein the steady absorption bolus volume of the absorption model is given by: B _steady= R _max· T _admin wherein B_steady is the steady absorption bolus volume, R_max is the maximum steady absorption rate, and T_admin is the administration time; wherein if the depot is empty at the beginning of the administration the resulting depot volume of the bolus while performing the administration is given as a function of time by: B_depot ⁢ ( t ⁢ ⁢ 1 ) = ∫ 0 t ⁢ ⁢ 1 ⁢ [ F ⁡ ( τ ) - R_max ] ⁢ ⅆ τ wherein B_depot is the depot volume, F is the actual flow, R_max is the maximum steady absorption rate, T_admin is the administration time and t 1 runs from zero at the beginning of the administration to the administration time; and wherein if the depot is not empty at the beginning of the administration, the resulting depot volume is given by: B_depot ⁢ ( t ⁢ ⁢ 1 ) = ∫ 0 t ⁢ ⁢ 1 ⁢ [ F ⁡ ( τ ) - R_max ] ⁢ ⅆ τ + B ⁢ ⁢ 0 ⁢ _depot wherein B 0 _depot is the initial depot volume.