Abstract: A sterile, closed drug delivery system (10) is provided comprising a flexible container (12), a capsule (22) coupled to the flexible container and a standard glass drug vial (36) positioned within the capsule. The flexible container has a liquid diluent therein. The capsule has supporting legs (32-35) which extend inwardly from the capsule to support the vial and also a highly flexible, pleated cap (28) which enables the drug vial to be manually moved relative to the supporting legs. The capsule is coupled to the flexible container by means of a hollow spike (54) located within the capsule and a frangible member (58) located within the flexible container, which frangible member allows fluid passage only when it is broken. Manual pressing of the pleated cap moves the drug vial downwardly onto the spike, piercing the stopper of the drug vial. Once the frangible member is broken, there is sterile communication between the drug vial and the liquid diluent contents of the flexible container.