Inclusion Criteria:

- Life expectancy >/= 12 weeks

- Availability and willingness to provide sufficient tumor tissue sample for testing

- Dose-escalation stage: Patients with histologically documented incurable, locally
advanced, or metastatic epithelial malignancy that has progressed despite standard
therapy or for which no standard therapy exists

- Expansion stage: Patients with one of the following epithelial,
histologically-documented, incurable, locally advanced, or metastatic tumor that has
progressed despite standard therapy or for which no standard therapy exists:
colorectal cancer, non-small cell lung cancer, head and neck squamous cell carcinoma,
or pancreatic cancer

- Use of an effective means of contraception (e.g., abstinence, hormonal or double
barrier method, surgically sterilized partner) for men and women of childbearing
potential while enrolled in the study

Exclusion Criteria:

- < 4 weeks since the last anti-tumor therapy prior to Day 1 of study treatment

- Major surgical procedure within 4 weeks prior to Day 1 of study treatment

- Leptomeningeal disease as the only manifestation of the current malignancy

- Active infection requiring IV antibiotics

- Active autoimmune disease that is not controlled by nonsteroidal anti-inflammatory
drugs

- Symptomatic hypercalcemia requiring continued use of bisphosphonate therapy

- Current severe, uncontrolled systemic disease

- History of cardiac heart failure of any New York Heart Association criteria or
serious cardiac arrhythmia requiring treatment

- History of myocardial infarction within 6 months before Day 1, or history of unstable
angina

- Clinically significant history of liver disease, including viral or other hepatitis,
current alcohol abuse, or cirrhosis

- History of interstitial lung disease

- History of severe allergic or hypersensitivity reaction to other therapeutic
antibodies that required discontinuation of therapy

- Known human immunodeficiency virus (HIV) infection

- Primary central nervous system (CNS) malignancy or untreated/active CNS metastases

- Significant traumatic injury within 4 weeks prior to Day 1 of study treatment

- Pregnancy or lactation