The primary objective of the study is to evaluate whether progression-free survival (PFS) is prolonged when veliparib is added to standard latinum-based chemotherapy and then continued as maintenance
(Arm 3 versus Arm 1). Progression-free survival as the primary study endpoint will be evaluated in both the whole subject population, as well as a more selective cohort of subjects with -deficient tumors
(gBRCA and/or sBRCA). Secondary objectives include overall survival (OS) (Arm 3 versus Arm 1, and Arm 2 versus Arm 1), safety of all three arms, and disease related symptom (DRS) scores (Arm 3 versus
Arm 1 and Arm 2 versus Arm 1) in both the whole population and 5RC4-deficient population.