Veliparib (ABT-888), an Oral PARP Inhibitor, and VX-970, an ATR Inhibitor, in Combination With Cisplatin in People With Refractory Solid Tumors

Ataxia-telangiectasia-related (ATR) protein kinase is central to the deoxyribonucleic acid (DNA) damage response and homologous recombination, activating a series of phosphorylation cascades, culminating in cell cycle arrest to allow time for DNA repair. Poly (ADP-ribose) polymerase (PARP) plays a pivotal role in base-excision repair of single strand breaks formed either due to direct genotoxic stress or during the processing of double strand breaks. Preclinical studies show ATR inhibitor M6620 (VX-970) synergizes with cisplatin to induce DNA damage and antitumor activity. The addition of PARP inhibitor veliparib with VX-970 allows for impairment of DNA repair, induction of a breast cancer gene (BRCA) null phenotype, and potentiation of the antitumor activity of cisplatin.