Passive Targeting

Cancer is an intricate and multifaceted disorder, with a wide range of therapeutic options available to patients. Traditional therapeutic aids are ineffective to achieve the desired results. The more promising technique, passive targeting, selectively delivers drugs to tumor sites in a controlled manner through enhanced permeation and retention (EPR) effect. In the EPR effect, drug particles preferentially accumulate in the tumor site due to their leaky vasculature and lack of lymphatic drainage, resulting in a prolonged circulation period and optimized uptake. Passive targeting offers excellent favors over conventional therapies and provides betterment in patient outcomes. However, the effectiveness of passive targeting can be compromised by various factors. Nanoparticles are specifically designed and extensively used as a delivery vehicle to passively accumulate drugs into a tumor’s unique microenvironment through the EPR effect. Polymeric nanoparticles, liposomes, micelles, and dendrimers are exclusively used as a delivery vehicle and are now in clinical trials. Passive targeting holds great promise as a cancer-targeting therapy and ongoing research efforts are focused on improving its efficacy and applicability in clinical trials.