Method and assembly for fluid transfer and drug containment in an infusion system

A drug container for use in an infusion system, said drug container comprising:

• a fixed dose of a medical substance, and
• a cap for sealing said drug container, said cap further comprising:
• a luer-lock connector for attachment to a corresponding connector provided on an inlet port of a container for infusion fluid, thereby creating a luer-lock coupling,
• a protruding member forming a fluid duct between said drug container and said luer connector, and
• a fluid barrier provided inside said fluid duct,
• wherein said drug container comprises a rigid material, said protruding member comprises a more flexible material than said luer-lock connector and said drug container, and said fluid barrier is made of a more brittle material than said drug container, said protruding member, and said luer-lock connector.