Targeted drug delivery is a method of delivering medication with the goal of maximizing its effects on specific parts of the body. This approach aims to minimize unwanted effects of the medication on non-diseased tissue, while at the same time prolonging the drug’s actions on its target.
Regular drug delivery utilizes blood circulation as a means to transfer the active substance to its target. The main disadvantage of that approach is that a very small percentage of the initial dose manages to reach the intended target, while the rest affects unintended cell populations. Targeted drug delivery aims to mitigate this exact issue by various ways.
Targeted drug delivery can be achieved by increasing the molecular specificity of the medication. An example of this approach is the use of monoclonal antibodies, which are commonly used in cancer treatment. Monoclonal antibodies are normally created by the immune system in response to a specific antigen, and they can only bind on cells that have that antigen on their surface. Thus, when creating monoclonal antibodies for different forms of cancer, scientists find protein targets that only exist on the surface of the cancer cells. This means that the treatment will only affect these cell populations, while having essentially no effect on any other cells they encounter through blood circulation.
When molecular specificity cannot be achieved, there is another effective way to increase drug concentration at the intended target site. Researchers have developed various delivery vehicles that can protect drugs from degradation and increase their amount in blood circulation, leading to higher concentrations and longer action time. Nanotechnology has played a significant role in the development of new delivery vehicles that can bypass the body’s immune response while being non-toxic.
Resources:
Drug Delivery: https://www.technologynetworks.com/drug-discovery/articles/drug-delivery-322035
Targeted Drug Delivery: https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/targeted-drug-delivery