# Niraparib

National Cancer Institute

## Source

National Cancer Institute. Niraparib. NCI Thesaurus. Code C80059.

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.