Pamiparib, also known as BGB-290, is a highly potent and selective PARP inhibitor with favorable drug metabolism and pharmacokinetic properties. BGB-290 selectively binds to PARP and prevents PARP-mediated repair of single-strand DNA breaks via the base-excision repair (BER) pathway. This enhances the accumulation of DNA strand breaks, promotes genomic instability, and eventually leads to apoptosis. BGB-290 may both potentiate the cytotoxicity of DNA-damaging agents and reverse tumor cell chemo- and radioresistance.