CVT-313 is a potent and selective inhibitor of CDK2 that prevents neointimal proliferation. CVT-313 has an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation.