- Currently taking strong or moderate inhibitors/inducers of cytochrome P450, family 3, subfamily A, polypeptide 4 (CYP3A4); Note: dinaciclib is a CYP3A4 substrate; patients should not take grapefruit/grapefruit juice or St. John's wort; use of strong or moderate CYP3A4 inhibitors is prohibited from < 7 days prior to registration; use of CYP3A4 inducers is prohibited from =< 7 days prior to registration