A new study has discovered an in vivo use of click chemistry that can rapidly clear drugs from circulation in case of emergency. Although it raises the possibility of a universal safety switch, its adoption by industry could be limited by the need to individually vet each chemical reactant, plus the product they create.
While click chemistry is a well-established tool for non-toxic labeling of biological molecules in research labs, the method has started to gain traction in drug development as well.
The reactions are attractive because they are "bioorthogonal," which means they can take place inside living systems without having any effect on endogenous biochemical processes. The reason is that the reactants have high selectivity for each other, but are biologically inert.
Jutta Wanner, VP of research at drug delivery company BlinkBio Inc., told BioCentury in vitro bioorthogonal reactions have been key for manufacturing conjugated biologics without disrupting the biochemistry of their protein components. The company is using the strategy to create tunable linkers that couple therapeutic payloads to targeting constructs, based on Fab fragments, which release the payloads in the low pH environment of a tumor.
At least two companies, Shasqi Inc. and Tagworks Pharmaceuticals B.V., are developing in vivo bioorthogonal chemistry platforms to deliver therapeutic compounds with precise spatial and temporal control. The idea is that by caging a drug with one bioorthogonal reactant, it becomes an inactive prodrug until it encounters the second reactant,