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% decrease with clinically significant symptoms

- 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