 The study seeks to assess the efficacy of veliparib ABT-888 in combination with carboplatin and etoposide in participants with extensive disease small cell lung cancer ED SCLC. ED SCLC is defined herein as any SCLC except a disease confined to the hemithorax of origin, with or without the involvement of regional lymph nodes, including ipsilateral and contralateral mediastinal, ipsilateral and contralateral mediastinal, and ipsilateral supraclavicular nodes 