Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically proven glioblastoma

- Stable disease following ≥ 4 cycles of adjuvant temozolomide

- No progression or recurrence of disease

PATIENT CHARACTERISTICS:

- HLA-A*02 positive

- ≥ 18 years old

- Life expectancy > 8 weeks

- Karnofsky performance status ≥ 60

- WBC >3,500/µL

- ALC >350/mm3

- ANC >1,500/mm3

- Platelet count >100,000/mm3

- Hemoglobin >10gm/dL

- AST, ALT and alkaline phosphatase <2.5 times upper limit of normal (ULN)

- Bilirubin <1.5 times ULN

- Creatinine <1.5 mg/dL and/or creatinine clearance >60cc/min

- Serum potassium, magnesium and calcium within normals levels (supplementation is
allowed)

- Not pregnant or nursing

- Negative pregnancy test

- Practice birth control during and for 2 months after treatment with IMA950 (both
genders)

- Women of childbearing age must agree to use adequate contraceptive methods

- No significant active hepatic, renal, infectious or psychiatric disease

- No HIV, active hepatitis infection, or any other active severe infectious disease

- No history of autoimmune disease or immunosuppression

- No clinically significant cardiovascular event within 3 months before study entry or
an increased risk for ventricular arrhythmia

- No malignancy other than glioblastoma that required treatment during the last 12
months

PRIOR and/or CONCURRENT THERAPY:

- See Disease Characteristics

- Completed radiotherapy and at least 4 cycles of adjuvant temozolomide

- Not be receiving steroids OR be on stable dose of steroids for ≥ 5 days prior to
registration

- No other prior immunotherapy for glioblastoma

- No major surgery within 4 weeks prior to treatment start

- At least 4 weeks from cytotoxic therapies (incl. temozolomide)

- At least 2 weeks from non-cytotoxic therapies (e.g. interferon, tamoxifen)

- At least 3 weeks from bevacizumab

- No current treatment with imiquimod; prior use of imiquimod is allowed