Drug Delivery Device with Front Loading Feature

A drug delivery system comprising:

• a cartridge comprising:
• a cylindrical body portion with an axially displaceable piston,
• a distal outlet portion and,
• coupling structure associated with the outlet portion and adapted to engage corresponding coupling structure on a needle assembly,
• a needle assembly comprising:
• a hollow needle having a distal end adapted to be arranged in fluid communication with the cartridge outlet portion, and
• a hub comprising coupling structure adapted to engage the cartridge coupling structure in a mounted state in which the hollow needle is arranged in fluid communication with the cartridge outlet portion,
• a drug delivery device comprising:
• a front-loaded cartridge holder assembly adapted to receive and hold a cartridge in a mounted state, comprising:
• cartridge holding structure actuatable between:
• an open loading state in which a cartridge can be received in a proximal direction and removed in a distal direction, and
• a closed operational state in which a received cartridge is held in an operational mounted position,
• the drug delivery system comprising:
• blocking structure configured to prevent the cartridge holding structure from being actuated between the closed and the open state when a cartridge with a mounted needle assembly is held in a mounted position.