The present invention discloses a method for the prevention of atherosclerosis, its genesis, progression and restenosis in human patients undergoing treatments for arterial lesions such as PTA or atherectomy, and which may be accompanied by stent implantation. Further, the treatment method disclosed has applicability in all stages of atherosclerosis in which monocytes play a role. The compound utilized in the present method as the active agent is a 2-halo-2'-deoxyadenosine such as 2-chloro-deoxyadenosine (2-CdA). The treatment method of the present invention includes the administration of 14 doses of 2-CdA in the amount of 0.12 mg/kg. One dose is given intravenously before the coronary intervention, another is given intravenously after the intervention and the remaining twelve doses are given subcutaneously at weekly intervals over a subsequent three month period.