A dual vial adapter assemblage for use with a drug vial, a liquid vial and a needleless syringe, the drug vial having a drug vial bottle and a drug vial stopper sealing the drug vial bottle, the drug vial containing a medicament, the liquid vial having a liquid vial bottle and a liquid vial stopper sealing the liquid vial bottle, the liquid vial containing liquid contents for mixing with or reconstituting the medicament in the drug vial to form a liquid drug therein, the needleless syringe having a male connector, the dual vial adapter assemblage having a longitudinal dual vial adapter assemblage centerline and comprising: (a) an integrally formed first vial adapter having a longitudinal first vial adapter centerline and including a transverse vial adapter top wall with an upright first vial adapter connector of a first connector type, an oppositely directed first vial adapter skirt for telescopic mounting on the drug vial, and a first vial stopper puncturing cannula for puncturing the drug vial stopper on said telescopic mounting said first vial adapter on the drug vial; (b) an integrally formed second vial adapter having a longitudinal second vial adapter centerline and including a transverse second vial adapter top wall with an upright second vial adapter connector of said first connector type, an oppositely directed second vial adapter skirt for telescopic mounting on the liquid vial, and a second vial stopper puncturing cannula for puncturing the liquid vial stopper on said telescopic mounting said second vial adapter on the liquid vial; and (c) a dual ended liquid transfer coupler having a pair of opposite coupler ends in the form of twin connectors (131, 132) of a second connector type for sealed engagement with said first vial adapter connector and said second vial adapter connector in a set-up position of the dual vial adapter assemblage such that said first vial adapter connector is in flow communication with said second vial adapter connector for forming the liquid drug in the drug vial, wherein one connector type of said first connector type and said second connector type is a female connector for sealed engagement with the needleless syringe's male connector and the other connector type of said first connector type and said second connector type is a male lock connector for screw thread sealed engagement with said female connector, the arrangement being such that, in use, for aspiration of the liquid drug from the drug vial, when said first vial adapter connector is configured as a female connector, the needleless syringe is directly attachable to said first vial adapter connector, and when said first vial adapter connector is configured as a male connector, the needleless syringe is directly attachable to said dual ended liquid transfer coupler attached to said first vial adapter connector. (a) an integrally formed first vial adapter having a longitudinal first vial adapter centerline and including a transverse vial adapter top wall with an upright first vial adapter connector of a first connector type, an oppositely directed first vial adapter skirt for telescopic mounting on the drug vial, and a first vial stopper puncturing cannula for puncturing the drug vial stopper on said telescopic mounting said first vial adapter on the drug vial; (b) an integrally formed second vial adapter having a longitudinal second vial adapter centerline and including a transverse second vial adapter top wall with an upright second vial adapter connector of said first connector type, an oppositely directed second vial adapter skirt for telescopic mounting on the liquid vial, and a second vial stopper puncturing cannula for puncturing the liquid vial stopper on said telescopic mounting said second vial adapter on the liquid vial; and (c) a dual ended liquid transfer coupler having a pair of opposite coupler ends in the form of twin connectors (131, 132) of a second connector type for sealed engagement with said first vial adapter connector and said second vial adapter connector in a set-up position of the dual vial adapter assemblage such that said first vial adapter connector is in flow communication with said second vial adapter connector for forming the liquid drug in the drug vial,