The present invention relates to a cap assembly for a drug delivery device comprising: - a cap body (26) to protect and to receive a distal dispensing end (14 50) of the drug delivery device (10), - an interlock member (24 40) operably engaged with the cap body (26) and being further adapted to releasably engage with a distal end section (21) of the devices dispensing end (14 50) to provide a safety lock for the cap body (26).
