The disclosure relates to a needle assembly adapted to couple with a medicament delivery device including a needle having a proximal tip and a distal tip, a needle hub coupled to the needle, a body adapted to engage the needle hub, a removable needle cap adapted to cover the distal tip, and a removable sealing element. The sealing element is adapted to seal an open proximal end of a compartment of the body, including the proximal tip, in such a manner that the proximal tip is housed in a sealed environment before use of the needle. The disclosure further relates to a medicament delivery device including such a needle assembly.