Extracellular therapeutic target drug

Further therapeutic benefit can be gained by ensuring that the chelating agent is delivered to target sites at an appropriate concentration, rate and duration. Ideally for maximal chelation, a drug must be present within the body at both a reasonable concentration and length of time to ensure interception of iron from either extracellular or intracellular iron pools. Compounds with short plasma half lives are thus likely to be less effective due to the limited pool of chelatable iron present within the body at any one time. 

Fig. 3.2 Challenges of systemic in vivo siRNA delivery. The in vivo application, especially systemic delivery of siRNA, is facing challenges from multiple hurdles in the extracellular environment and various barriers for the intracellular uptake. Addressing those issues is critical for efficient in vivo delivery of siRNA in prechnical animal models for drug target vahdation and potential therapeutics...

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