NCIt definition : An orally bioavailable inhibitor of poly (ADP-ribose) polymerase (PARP) types 1 and
2 (PARP-1 and -2), with antineoplastic activity. Upon administration, niraparib binds
to and inhibits the activity of PARP-1 and -2, thereby inhibiting PARP-1 and -2-mediated
DNA repair, enhancing the accumulation of DNA strand breaks, promoting genomic instability
and resulting in apoptosis. The PARP family of proteins catalyzes post-translational
ADP-ribosylation of nuclear proteins and is activated by single-strand DNA (ssDNA)
breaks.;