EPR effect: Promising approach for tumor targeted drug delivery

Abstract

Targeted drug delivery to tumor sites is one of the ultimate goals in drug delivery. Recent advances in nanoparticles engineering has certainly improved drug targeting, however clinical effects are disappointing. Present review addresses challenges in cancer therapy and current status of tumor targeted drug delivery. Most of the efforts have been directed towards design and surface manipulation of nanoparticles with relative little attention to other aspects. EPR effect based drug delivery offers lower cost of therapy, greater therapeutic effects on more types of tumors and fewer adverse effects. Present review focuses on basic understanding of EPR effect, critical attributes of nanoparticles influencing success of EPR based drug delivery and factors involved in EPR effect. Tumor biology diversity is responsible for heterogeneity of EPR effect which reduces its universal validity. Augmentation of EPR effect overcomes heterogeneity, thus widening its application on more types of tumors. Clinical outlook of SMANCS, clinically successful macromolecular drug is presented to support the concept of EPR effect in tumor targeted drug delivery.