Additional Study Information: By doing this study, researchers hope to learn more about the efficacy (how well the drug works) and safety (the drugs side effects) of MORAb-202 (farletuzumab ecteribulin) compared to approved chemotherapy medications in patients with platinum-resistant ovarian cancer. The study will evaluate two doses of MORAb-202. MORAb-202, is made up of two parts; an antibody which targets specific proteins on the cancer cell surface and a chemotherapy drug. The antibody is absorbed into the cell and once inside the chemotherapy drug is released to attack the cancer cell. The treatment being studied, MORAb-202, is investigational, which means its safety and effectiveness have not been established and it is not approved by the United States Food and Drug Administration (FDA) for ovarian cancer. The study chemotherapy medications are approved by the FDA and are standard-of-care treatments for your type of ovarian cancer.