Purity >99% by HPLC. Potent inhibitor of Poly(ADP-Ribose) polymerase PARP-1 and PARP-2. Its potency against PARP is validated to be 5 nM in vitro. Does not inhibit other NAD-binding enzymes. It significantly increased tumour growth delay resulting from radiation and DNA-damaging agents at well-tolerated doses in murine models. It shows minimal CYP450 inhibition and induction.