Drug Delivery Device and Method to Modify a Drug Delivery Device

A drug delivery device, comprising:

• a housing;
• a drive mechanism;
• a cartridge containing a drug, the cartridge being retained in a defined position relative to the housing, wherein the drive mechanism is configured to dispense drug from the cartridge;
• and
• a cartridge bias system, which comprises at least one resilient member and at least one rigid force transfer body,
• wherein the rigid force transfer body is movably retained in the housing, wherein the cartridge bias system is arranged and configured to exert a force on the cartridge to maintain the cartridge in the defined position, wherein the force is provided by the at least one resilient member, and wherein the rigid force transfer body is operatively connected to the at least one resilient member such that the force is reacted by the rigid force transfer body.

An arrangement comprising:

• a first drug delivery device comprising:
• a housing,
• a first drive mechanism,
• a first cartridge containing a drug, the first cartridge being retained in a defined position relative to the housing, wherein the first drive mechanism is configured to dispense drug from the first cartridge, and
• a first cartridge bias system, which comprises at least one resilient member and at least one rigid force transfer body,
• wherein the rigid force transfer body is movably retained in the housing, wherein the first cartridge bias system is arranged and configured to exert a force on the first cartridge to maintain the first cartridge in the defined position, wherein the force is provided by the at least one resilient member, and wherein the rigid force transfer body is operatively connected to the at least one resilient member such that the force is reacted by the rigid force transfer body;
• and
• a second drug delivery device comprising a second cartridge, a second cartridge bias system, and a second drive mechanism,
• wherein the first cartridge and the second cartridge have different lengths and/or diameters, wherein the rigid force transfer body of the first cartridge bias system compensates or is suitable to compensate differences in the different lengths and/or diameters of the first cartridge and the second cartridge.

A method of modifying a drug delivery device for use with a first cartridge having a diameter or length smaller than a diameter or length of a second cartridge containing a drug, the drug delivery device comprising the second cartridge and a cartridge bias system configured to exert a force onto the second cartridge, wherein the method comprises:

• determining a difference between the diameter or length of the first cartridge and the diameter or length of the second cartridge;
• providing a rigid force transfer body which is dimensioned to compensate the difference;
• and
• integrating the rigid force transfer body into the cartridge bias system to provide a modified drug delivery device.