Beyond the ATP-binding pocket: emerging strategies in kinase targeting from allosteric inhibition to targeted protein degradation.
Protein kinases are central regulators of cellular signaling and remain a major target class in precision medicine. While ATP-competitive inhibitors-including conformation-selective and covalent agents-have delivered substantial clinical benefit, durable responses are frequently limited by the conservation of the ATP pocket and the emergence of resistance mutations (e.g. gatekeeper and solvent-front substitutions), as well as kinase noncatalytic functions that are not addressed by enzymatic inhibition alone. Consequently, kinase drug discovery is expanding beyond orthosteric occupancy toward modalities that reprogram kinase conformations or eliminate the target protein. This Review summarizes the structural and medicinal chemistry principles underlying (i) allosteric inhibition and (ii) proximity-induced degradation, with an emphasis on design logic, structure-activity relationships, and key liabilities in the beyond rule of five space. We further highlight enabling technologies-including structural biology, chemical proteomics, and AI/ML-assisted modeling-that support allosteric site identification, ternary complex engineering, and multi-parameter optimization. Finally, we discuss translational challenges for bifunctional molecules, including permeability, exposure-response relationships, off-target degradation, and safety, and propose practical considerations for developing next-generation selective kinase therapeutics.