Inclusion Criteria

INclusion Criteria:

- Diagnosis of glioblastoma multiforme (GBM) or gliosarcoma (GS)

- In first, second, or third relapse

- History of low-grade glioma with transformation to GBM or GS allowed

- Considered to be in first relapse at first documented diagnosis of GBM or
GS

- Measurable or evaluable disease by contrast MRI

- Must have failed prior treatment that included external beam radiotherapy with or
without chemotherapy

- Epidermal growth Factor Receptor-positive and PTEN wild-type by immunohistochemistry

PATIENT CHARACTERISTICS:

- Karnofsky performance status 60-100%

- WBC ≥ 3,000/mm³

- Absolute neutrophil count ≥ 1,500/mm³

- Platelet count ≥ 100,000/mm³

- Hemoglobin ≥ 10 g/dL (transfusion allowed)

- SGOT < 2 times upper limit of normal (ULN)

- Bilirubin < 2 times ULN

- Creatinine < 1.5 mg/dL OR creatinine clearance ≥ 60 mL/min

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective hormonal or barrier method contraception before,
during, and for at least 12 weeks after completion of study treatment

- No other cancer within the past 3 years except nonmelanoma skin cancer or carcinoma
in situ of the cervix

- No active infection

- No other disease that would obscure toxicity or dangerously alter study drug
metabolism

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- More than 4 weeks since prior and no concurrent radiotherapy

- At least 4 weeks since prior and no concurrent cytotoxic chemotherapy agents (e.g.,
temozolomide) (6 weeks for nitrosoureas)

- At least 2 weeks since prior and no concurrent noncytotoxic chemotherapy agents

- At least 4 weeks since prior investigational agents

- No other concurrent investigational agents

- No prior erlotinib hydrochloride or other epidermal growth factor receptor
tyrosine-kinase inhibitors

- At least 2 weeks since prior enzyme-inducing antiepileptic drugs (EIAEDs), if not
used concurrently with study treatment

- Concurrent continuous use of EIAEDs allowed provided the patient has received
the drug for ≥ 2 weeks prior to study treatment

- No concurrent immunotherapy or anticancer hormonal therapy

- No other concurrent antineoplastic or antitumor agents

Exclusion Criteria:

Patients meeting any of the following criteria are ineligible for study entry:

- Patients with a history of any other cancer (except non-melanoma skin cancer or
carcinoma in-situ of the cervix), unless in complete remission and off of all therapy
for that disease for a minimum of 3 years are ineligible.

- Patients must not have active infection

- Patients must not be pregnant/breast feeding and must agree to practice adequate
contraception. Women of childbearing potential must have a negative B-HCG pregnancy
test documented within 14 days prior to treatment. Patients must not be pregnant
because of the uncertainty that study drug may be potentially embryotoxic. For this
reason, women of child-bearing potential and men must agree to use adequate
contraception (hormonal or barrier method of birth control) prior to study entry, for
the duration of study participation, and continue approximately 12 weeks after the
study is completed. If condoms are used as a barrier contraceptive, a spermicidal
agent should be added to ensure that pregnancy does not occur. Should a woman become
pregnant or suspect she is pregnant while participating in this study, she should
inform her treating physician immediately.

- Prior treatment with Tarceva, or other EGFR tyrosine-kinase inhibitors will not be
allowed.

- Patients must not have any disease that will obscure toxicity or dangerously alter
drug metabolism.