In human whole blood assays, BMS-986195 potently inhibited BCR-stimulated expression of CD69 on B cells with an IC50 of 11 nM. BMS-986195 is highly selective, providing >5,000-fold selectivity for BTK over 240 kinases with only the 4 related Tec family kinases demonstrating less than 5000-fold selectivity (9 - 1,000-fold).