This is a Phase I, multicenter, open-label, dose-escalation study of DMUC4064A a dministered by intravenous (IV) infusion every three weeks (q3w) to cancer patie nts. The study will employ a traditional 3 + 3 dose escalation design to determi ne the maximum tolerated dose (MTD) of DMUC4064A against platinum-resistant ovar ian cancer. Once a q3w recommended phase II dose (RP2D) is identified, two expan sion cohorts (one in platinum-resistant ovarian cancer and another in unresectab le pancreatic cancer) may be evaluated to further characterize the safety and ac tivity in these patient populations. Time on treatment is expected to last appro ximately 1 year.