Using porous hollow fiber membranes, systems/methods for continuously synthesizing polymer-coated particles by anti-solvent crystallization are provided. The disclosed systems/methods provide for synthesis of polymer-coated drug particles/crystals from solutions of the polymer and the drug particles in suspension by exposing the solution to an anti-solvent through a porous hollow fiber device. A feed solution of a coating polymer with suspended drug particles can be exposed to an anti-solvent through hollow fiber pores, thereby causing the polymer to precipitate on and coat the drug particles. In addition, a feed solution of a coating polymer with drug in solution can be exposed to an anti-solvent through hollow fiber pores, thereby causing the drug to crystallize from the solution and the polymer to precipitate/coat the drug. Results indicate that a uniformly coated, free-flowing product may be developed in this advantageous porous hollow fiber anti-solvent crystallization method. The coated drug particles can be used for controlled release of the drug, and the molecule and the crystal structure are not affected by the process.