[Development of gas-driven pump intended for implantation for long-term administration of drugs]

A prototype is presented of a new, implantable therapeutic system for parenteral long-term administration of drugs. It consists of a casing with two chambers separated by a membrane. One of the chambers contains the dissolved substance and includes an interchangeable device to expel the substance. This chamber can be refilled transcutaneously through an opening which is then reclosed. The other chamber contains an isobarically expandable propulsive substance which exerts pressure upon the membrane to cause the solution to be expelled. The liberation time depends upon the particular expelling device used and the viscosity of the medicinal solution. The pharmaceutical and technological aspects of the applicability of this prototype in vitro are examined and discussed.