An improved intraocular lens has at least one filamentary haptic composed of a continuous matrix material interspersed with a toughening amount of discrete particles of a multistage, sequentially produced elastomeric polymer. An improved process for preparing a single-piece intraocular lens involves preparing a composite lens blank by molding pellets composed of a continuous polymeric material interspersed with particles of a multistage, sequentially produced elastomeric polymer about a central optic lens core so as to produce a single lens blank having a toughened annular region surrounding the central optic region, and then machining at least one filamentary haptic from the toughened annular region to prepare the lens.