Abstract: A treatment wire is provided for the delivery of a treatment to a site within the body that is composed of two stages. This treatment wire includes a single wire drive portion that is optimal for the proximal end of the treatment wire and engages any storage and/or drive mechanism that may be used in storing and/or deploying the treatment wire. The single drive wire is ground at its distal end to a smaller diameter and encased within a tube forming the second stage of the treatment wire. Because the drive wire terminates proximally to the tube, a cavity is formed that can retain the treating substance to be delivered to the patient. Shape-memory/superelastic material is preferably used for the construction of the treatment wire. When such material is used, the distal end of the treatment wire can be heat treated in order to render it more ductile and, therefore, more desirable for use in the tortuous passageways of the body.