Phase II Study Investigating the Efficacy and Activity of Single Agent Erlotinib in Chemotherapy-Naive Androgen Independent Prostate Cancer

Inclusion Criteria:

- Documented prostate cancer regardless of Gleason score

- Patients should be considered hormone refractory and androgen independent. They must
fail LHRH analogues, and anti-androgen withdrawal trial.

- Failure is confirmed by an increase in PSA value of 10% or more than the value
immediately before, and confirmed by another assessment 2 weeks later.

- Patients have to have measurable disease either biochemically using rising PSA or/and
with metastatic disease to the bone or visceral organs.

- Performance status of 2 or less using ECOG scale.· Adequate liver function tests with
ALT/AST being < 3x normal, total bilirubin of 1.5 or less, and adequate renal
function measured by a creatinine of 2.0 mg/dl or less. Alkaline phosphatase values
are never exclusion criteria if it is deemed related to bone metastases.

- Patients need to have adequate bone marrow function. ANC of 1000 or above, Hgb of 9.0
g/dl or above, and platelets of 100,000 or above. If other causes are affecting plts
counts such as autoimmune disorders, patients are allowed on study.

- Patients with inadequate bone marrow function that is deemed related to bone marrow
involvement with prostate cancer are allowed at the investigator's discretion.

- Patients with other malignancies are allowed as long as there is no evidence of the
other malignancy present at entry time, and it has been 3 years or more since the
treatment for the other disorder was completed.

- Patients with prior exposure to investigational therapies including vaccines are
allowed on this study as long as their last exposure was 4 weeks prior to study
entry.Patients with known bone metastases are allowed to receive intravenous
bisphosphonates such as aredia or zometa.

- Patients on oral bisphosphonates are also allowed.

- Chemo Naive

Exclusion Criteria:

- Patients with prior exposure to Tarceva

- Patients who have received any prior systemic chemotherapy for prostate cancer.
Exposure to chemotherapy for other malignancies is allowed as long as last
chemotherapy was completed 3 years prior to study entry.

- Patients with prior malignancies are excluded except for those who have non-melanoma
skin cancers or other cancers that are in remission with the last therapy given 3
years prior to enrollment.

- Prior exposure to any form of steroids is allowed and is not considered exclusion
criteria.

- Performance status of 3 or above using ECOG scale.

- Known HIV positive status Known CNS involvement with prostate cancer