Innovative strategies for measuring kinase activity to accelerate the next wave of novel kinase inhibitors

•Kinase activity is an intricate biochemical reaction.•Kinase activity assays use distinct approaches to measure kinase activity.•Challenges in PKI development can be overcome by using kinase activity assays during all development phases.•No one-size-fits-all kinase activity assay exists thus further development of assays is necessary. The development of protein kinase inhibitors (PKIs) has gained significance owing to their therapeutic potential for diseases like cancer. In addition, there has been a rise in refining kinase activity assays, each possessing unique biological and analytical characteristics crucial for PKI development. However, the PKI development pipeline experiences high attrition rates and approved PKIs exhibit unexploited potential because of variable patient responses. Enhancing PKI development efficiency involves addressing challenges related to understanding the PKI mechanism of action and employing biomarkers for precision medicine. Selecting appropriate kinase activity assays for these challenges can overcome these attrition rate issues. This review delves into the current obstacles in kinase inhibitor development and elucidates kinase activity assays that can provide solutions.