Potency assay (off target):
Selectivity within family (IC50):
CDK1/B1 30 nM, CDK2/cyclin E1 0.6 nM, CDK2/cyclin A2 2.5 nM, CDK3/cyclin E1 15.1 nM, CDK4/cyclin D1 125 nM, CDK5 23.1 nM, CDK5/p25 21.4 nM, CDK6/cyclin D3 349 nM, CDK7 >10000 nM,
CDK9/cyclin T1 62 nM
Broader kinase selectivity profile of INX-315 was assessed using the LanthaScreen Eu Kinase Binding and Z’-Lyte Kinase Assays. Treatment with 100 nM INX-315 caused ≥94% inhibition of CDK2/cyclin A/A1/E1/O and caused ≥80% inhibition of CDK3/cyclin E1, CDK5 (inactive), CDK5/p25, CDK5/p35, colony stimulating factor 1 receptor (CSF1R), MAPK15/ERK7, neurotrophic tyrosine receptor kinase (NTRK)/tyrosine receptor kinase (TRK)C, and tyrosine receptor kinase (TYK)2.
Follow-up experiments showed INX-315 displayed selectivity for CDK2/cyclin A1/E1/O with IC50 values of 4 nM or less. CSF1R had an IC50 of 2.29 nM, while all other targets had IC50 values greater than 10 nM.