Inclusion Criteria:

• Men and women age ≥ 18 years
• For patients with metastatic basal cell carcinoma, histologic confirmation of distant BCC metastasis (e.g., lung, liver, lymph nodes, or bone), with metastatic disease that is RECIST measurable using CT or MRI
• For patients with locally advanced BCC, histologically confirmed disease that is considered to be inoperable
• For patients with locally advanced BCC, radiotherapy must have been previously administered for their locally advanced BCC, unless radiotherapy is contraindicated or inappropriate. For patients whose locally advanced BCC has been irradiated, disease must have progressed after radiation.
• For women of childbearing potential, agreement to the use of two acceptable methods of contraception, including one barrier method, during the study and for 12 months after discontinuation of GDC-0449
• For men with female partners of childbearing potential, agreement to use a latex condom, and to advise their female partner to use an additional method of contraception during the study and for 3 months after discontinuation of GDC-0449

Exclusion Criteria:

• Prior treatment with GDC-0449 or other Hedgehog pathway inhibitors
• Pregnancy or lactation
• Life expectancy of < 12 weeks
• Patients with superficial multifocal BCC who may be considered unresectable due to breadth of involvement
• Concurrent non-protocol-specified anti-tumor therapy (e.g., chemotherapy, other targeted therapy, radiation therapy, or photodynamic therapy)
• Recent, current, or planned participation in an experimental drug study
• History of other malignancies within 3 years of Day 1, except for tumors with a negligible risk for metastasis or death, such as adequately treated squamous-cell carcinoma of the skin, ductal carcinoma in situ of the breast, or carcinoma in situ of the cervix
• Uncontrolled medical illnesses such as infection requiring treatment with intravenous antibiotics