A fluid transfer device comprises an access cannula assembly including a cannula having a proximal end, a distal end and a lumen therethrough, a cutting edge at the distal end of the cannula for piercing a vial stopper and a hub having an open proximal end and a distal end joined to the proximal end of the cannula so that the lumen is in fluid communication with the proximal end of the hub. A blunt cannula assembly includes a blunt cannula having a proximal end, a distal end, and a passageway therethrough, and a housing having an open proximal end and a distal end joined to the proximal end of the cannula. A spring is provided for helping to position the access cannula within the passageway of the blunt cannula wherein a proximally directed force applied to the blunt cannula will cause the spring to deflect and the cutting edge of the access cannula to project distally outwardly past the distal end of the blunt cannula.