Naltrexone, a narcotic antagonist, can be an effective drug in the treatment of opiate addiction. However, problems of drug addiction remain. Clinical management of drug addiction requires a complex association of many factors. One obstacle in achieving success with drug treatment regimes is in patient compliance in taking the prescribed drugs. In work dealing with the treatment of narcotic addiction our team earlier developed for NIH/NIDA a biodegradable controlled release delivery system in the form of implantable beads made from a polylactic- co-glycolic acid (PLGA) polymer. In preliminary clinical studies, a single dose of naltrexone, given in these implantable beads, mitigated the opiate effects of morphine challenges for up to one month after administration. These beads were of immediate utility in evaluating the concept of using an implant in treatment regimes for drug abuse. Our firm has developed proprietary non-solvent technologies for the formulation of PLGA/drug controlled release systems which maintain the advantageous characteristics of earlier solvent-based drug delivery systems. In this program, we are further developing one of these types of non-solvent controlled release systems with the goal of a single-dose PLGA/naltrexone treatment for use in a one-month treatment regimen specific for the management of drug abuse. Because of the non-solvent formulation basis to our technologies, the resultant system will find more ready acceptance by the FDA when both planning clinical trials and final product development.