A drug vial adapter according to the invention includes: a first coupling member having a female luer connector (preferably a luer lock) with a fluid path therethrough, a flange having a first sealing ring seat formed therein and a first mating structure; a second cylindrical coupling member having...http://www.google.com/patents/US5833213?utm_source=gb-gplus-sharePatent US5833213 - Multiple dose drug vial adapter for use with a vial having a pierceable septum and a needleless syringe 
