A 2-part, Phase 2 controlled, open-label, randomized study in participants with platinum-resistant recurrent ovarian cancer. In Part 1, participants received SGI-110 and carboplatin. The optimum dose of SGI-110 (guadecitabine) was identified in Part 1 based on safety and efficacy. In Part 2, participants were randomized to receive the dose identified in Part 1 plus carboplatin or one of four treatment of choice at the discretion of the investigator. The treatment of choice consisted of topotecan, pegylated liposomal doxorubicin, paclitaxel or gemcitabine.