A Study Evaluating the Safety and Pharmacokinetics of DMUC4064A in Participants With Platinum-Resistant Ovarian Cancer or Unresectable Pancreatic Cancer

Inclusion Criteria:

Life expectancy of at least 12 weeks
Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1
Measurable disease is defined as at least one bi-dimensionally measurable non-lymph node lesion greater than or equal to (>/=) 1 centimeter (cm) on long access diameter on computed tomography (CT) or magnetic resonance imaging (MRI) scan or at least one bi-dimensionally measurable lymph node measuring >/=1.5 cm on short access diameter on CT or MRI scan
Adequate hematologic, kidney and liver function
Highly effective contraception as defined by the protocol Participants with Ovarian Cancer
Histological documentation of epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer
Documentation of mucin 16 (MUC16) expression by either serum carcinoma antigen 125 (CA125) >=2 x Upper limit of normal (ULN) or by immunohistochemistry [IHC] by central review
Disease that has progressed or relapsed during or within 6 months after the most recent treatment with a platinum-containing chemotherapy regimen
Progression or relapse from prior platinum-based chemotherapy must be documented radiographically by RECISTv1.1 criteria

For ovarian cancer dose expansion cohorts only:

Not more than two prior chemotherapy regimens for the treatment of platinum-resistant ovarian cancer

Participants with Pancreatic Cancer:

Histologic documentation of incurable, locally advanced, or metastatic pancreatic ductal adenocarcinoma consisting of unresectable pancreatic ductal adenocarcinoma (i.e., participants who are not considered eligible for surgical resection with curative intent), including recurrence of previously resected disease
Documented MUC16 expression from archival or fresh tissue by IHC central review
Participants for whom no further standard of care therapy exists, must have received standard of care chemotherapy in the adjuvant or advanced/metastatic setting
No more than two prior chemotherapy regimens administered for the treatment of pancreatic cancer in the adjuvant or advanced/metastatic setting

Exclusion Criteria:

Anti-tumor therapy, including chemotherapy, biologic, experimental, or hormonal therapy within 4 weeks prior to Day 1
Prior treatment with MUC16 targeted therapy (e.g., oregovomab [OvaRex] or abagovomab) including DMUC5754A
Prior treatment with a monomethyl auristatin E (MMAE)-containing antibody-drug conjugate (ADC)
Palliative radiation to bone metastases within 2 weeks prior to Day 1
Prior radiation to lung fields
Major surgical procedure within 4 weeks prior to Day 1
Known active bacterial, viral, fungal, mycobacterial, parasitic, or other infection (including human immunodeficiency virus [HIV] and atypical mycobacterial disease but excluding fungal infections of the nail beds) at study enrollment or any major episode of infection requiring treatment with IV antibiotics or hospitalization (relating to the completion of the course of antibiotics) within 4 weeks prior to Cycle 1, Day 1
Evidence of significant uncontrolled concomitant diseases, such as ocular toxicities, diabetes, cardiovascular disease; nervous system, renal, hepatic, endocrine, or gastrointestinal disorders; autoimmune disease, or a serious non-healing wound or fracture
Clinically significant pulmonary symptoms and signs, any active pulmonary or respiratory infection at enrollment, pulmonary infiltrates on screening CT scan of the chest that are associated with symptoms (including dyspnea), resting or exercise arterial oxygen saturation (SpO2) less than (<) 90 percent (%), requirement for supplementary oxygen at rest or exercise (either continuously or intermittently), moderate (40%-60% predicted) or severe (<40% predicted) decreased diffusing capacity for carbon monoxide (DLCO) or mild (>60% Clinically significant history of liver disease, including viral or other hepatitis, current alcohol abuse, or cirrhosis
Other malignancy within the last 5 years, except for adequately treated carcinoma in situ of the cervix, squamous carcinoma of the skin, adequately controlled limited basal cell skin cancer, or synchronous primary endometrial cancer or prior primary endometrial cancer if protocol criteria are met
Untreated or active central nervous system (CNS) metastases. Participants with a history of treated CNS metastases may be eligible
Current Grade greater than (>) 1 toxicity (except alopecia and anorexia) from prior therapy or Grade >1 neuropathy from any cause
History of severe allergic or anaphylactic reactions to monoclonal antibody therapy (or recombinant antibody-related fusion proteins)
Pregnancy or breastfeeding
Inability to comply with study and follow-up procedures
Any other diseases, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or that may affect the interpretation of the results or render the participants at high risk from treatment complications