Issues and perspectives on the biocompatibility and immunotoxicity evaluation of implanted controlled release systems.

Over the past decade, significant advances and discoveries in cell and molecular biology and biomaterials have provided a foundation for the research and development of new, complex controlled release systems. Many of these new controlled release systems utilize active biological components, i.e., proteins and cells, to achieve their intended therapeutic goal. Utilization of bioactive biological materials in implantable controlled release systems has prompted a broad as well as an in-depth interest in the safety and efficacy of these systems. This short review is intended to provide individuals with a perspective on standards and guidance documents which specifically address biological and immunotoxicity response evaluation for safety of controlled release systems from a regulatory point of view.