Pilot Study of PLX3397 in Patients With Advanced Castration-Resistant Prostate Cancer (CRPC)

Inclusion Criteria:

- Histologically confirmed prostate cancer, currently with objective progressive
disease.

- Castrate level of testosterone (<50 ng/dL).

- Baseline circulating tumor cell (CTC) count ≥10/7.5 mL blood.

- Archival tumor tissue (unstained sections, paraffin block, or frozen tumor tissue)
has been requisitioned for shipment to the central laboratory.

- Karnofsky performance status of 80-100.

- Adequate organ and marrow function.

Exclusion Criteria:

- The subject has received:

- Any systemic chemotherapy (including investigational agents) within 4 weeks
(with the exception of nitrosoureas/mitomycin C within 6 weeks), of the first
dose of study treatment, OR

- Biological agents (antibodies, immune modulators, cytokines, or vaccines) within
6 weeks of the first dose of study treatment, OR

- Hormonal anticancer therapy (not including LHRH agonists or antagonists) within
2 weeks before the first dose of study treatment. Specific restrictions on prior
hormonal and other anticancer treatments are detailed in inclusion criterion, OR

- Small-molecular kinase inhibitors or any other type of investigational agent
within 4 weeks before the first dose of study treatment or 5 half-lives of the
compound or active metabolite, whichever is shorter.

- The subject has received drugs used to control loss of bone mass (e.g.,
bisphosphonates) within 4 weeks prior to the first dose of study treatment.

- The subject has symptomatic or uncontrolled brain metastasis or epidural disease
requiring current treatment including steroids and anti-convulsants.

- The subject has a corrected QT interval calculated by the Fridericia formula (QTcF)
>450 ms at screening.

- The subject has uncontrolled or significant intercurrent illness including, but not
limited to, the following conditions:

- Cardiovascular disorders such as symptomatic congestive heart failure (CHF),
*Uncontrolled hypertension

- Unstable angina pectoris, clinically-significant cardiac arrhythmias

- History of stroke (including transient ischemic attack [TIA] or other ischemic
event) within 6 months of study treatment

- Myocardial infarction within 6 months of study treatment

- History of thromboembolic event requiring therapeutic anticoagulation within 6
months of study treatment or main portal vein or vena cava thrombosis or
occlusion.