Unmet Need: The binding affinity of a drug for its target is perhaps the most essential parameter when assessing drug efficacy, however it is often calculated in vitro within purified systems, which do not accurately represent patient-specific kinetics. More recently, strategies have been developed for chemically labeling compounds and their targets, either fluorescently, radioactively, or metallically, allowing for better assessment of target binding in cells and animals. Chemical labeling of compounds or targets, however, creates a costly technological barrier and safety considerations for the use of these technologies in humans. Label-free technology that could produce comparable results could be adopted quickly in clinics because of their safety profile and lower cost.
Technology Overview: Johns Hopkins researchers have developed an MRI method of imaging the binding of small molecular agonists to specific targets, such as for instance receptors in the body. Radio frequency irradiation specific for aliphatic protons of this molecule is used to noninvasively and transiently label a compound of interest, e.g. a drug, in situ in the tissue. When the compound binds to its target, this magnetic label gets transferred to it. Continuous irradiation of the unbound compound is done to repeat this process enhancing sensitivity. Eventually, this label gets transferred from the receptor to water molecules, and detected by MRI and quantified. Contrary to most methods, this technique is especially suitable for low-affinity binding. The sensitivity and specificity of the technique is greatly improved over comparable methods, including saturation transfer difference (STD) and pharmacologic MRI (phMRI).
Stage of Development: The inventors have demonstrated that they can detect a tissue concentration of 2.5mM caffeine in mice as specific magnetic resonance frequency emissions using standard MRI equipment. They can map the target binding to specific regions of the body, e.g. the brain, much like fMRI/phMRI.
Disease Indication: Cancer, Neuological Disorders
Technology Classification: Therapeutics, Drug Discovery, Imaging of Therapeutic efficacy
Patent Status: Pending
