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NCI Drug Dictionary

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The NCI Drug Dictionary contains technical definitions and synonyms for drugs/agents used to treat patients with cancer or conditions related to cancer. Each drug entry includes links to check for clinical trials listed in NCI's List of Cancer Clinical Trials.

niraparib tosylate monohydrate
Patient Information
An orally bioavailable, hydrated, tosylate salt form of niraparib, an 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. Check for active clinical trials using this agent. (NCI Thesaurus)

US brand name:Zejula
Chemical structure:2H-indazole-7-carboxamide, 2-(4-(3S)-3-piperidinylphenyl)-, 4-methylbenzenesulfonate, hydrate (1:1:1)