A covered stent including an endovascular implant having a polymeric stent structure with an integrally formed membrane-like graft component, also referred to as a stent-graft, and methods of manufacturing the one-piece stent-graft by an injection molding process. A molding system for creating the polymeric stent structure is injected with a melt stream of moldable material that is forced between a parting line of the molding system to create a thin, flexible membrane-like structure within the open areas or interstitial spaces of the molded stent structure. The stent-graft so created is a one-piece, unified structure molded from a polymeric material in a single manufacturing step.
