A port assembly (418) comprising: a port housing (482) defining a first opening at a proximal end thereof, said first opening providing access to a cavity (506) within said port housing, said port housing defining a second opening, said second opening providing access to said cavity (506), a moveable plug (489) sealing said second opening an actuator (484) positioned within said cavity (506) of said port housing, said actuator having a proximal end portion and a plurality of sidewall members (501) extending axially from said proximal end portion toward said first opening of the port housing, one or more openings being defined between said sidewall members, said sidewall members have a terminal end spaced from said proximal end portion of said actuator, and a central cavity (521) defined by said sidewall members (501), said actuator adapted to force a stopper (528) into a vial during an activation step and a retainer (486) positioned in the cavity (506) defined by said port housing (482), said retainer having a plurality of retaining tabs (520,522), at least one of said plurality of retaining tabs adapted to retain a vial in a first, docked position, and at least one of said plurality of retaining tabs having a second length adapted to retain a vial in a second, activated position.
