A resealable cap (110, 210) for a medicament
vial (114, 214) has a base portion (112, 212) formed of vulcanized rubber or like material known for providing a stable environment for the medicament contained within the
vial, and a resealable portion (126, 226) overlying the base portion. The resealable portion (126, 226) is made of low-density
polyethylene or like material, and can be punctured by a needle or like injection member (140, 282) for dispensing medicament into the
vial (114, 214). Prior to filling, the cap (110, 210) is assembled to the vial (114, 214) and the cap / vial
assembly is sterilized. Then, a needle (140, 282) is inserted through the cap (110, 210) and medicament is introduced through the needle and into the vial. Upon withdrawal of the needle (140, 282), the penetrated region of the cap (248) is fused by
laser (276) or direct heat sealing (264) to hermetically seal the needle hole (294) in the cap.