A Phase II Trial of Tamoxifen and Bortezomib in Patients With Recurrent High-Grade Gliomas

This study will determine whether the drugs tamoxifen and bortezomib can delay tumor growth in patients with recurrent glioma (malignant brain tumor). Tamoxifen may work by interfering with the internal signaling needed for the cancer to grow. Bortezomib may also interfere with tumor growth processes. Laboratory studies show that low doses of bortezomib significantly enhance glioma cell death when used with tamoxifen.

Patients 18 years of age and older with glioma whose tumor does not respond to standard medical treatment and who are not taking enzyme-inducing anti-seizure medications such as Dilantin, phenobarbitol, or Tegretol, may be eligible for this study. Candidates are screened with a physical examination, blood tests, and magnetic resonance imaging (MRI) or computed tomography (CT). MRI and CT scans produce images of the brain that can show if the brain tumor is growing (see below).

Participants receive treatment in 6-week cycles for up to 1 year. (The treatment duration may be extended in some patients who continue to tolerate the drug and show no signs of tumor growth after 1 year.) During each cycle, patients take six tamoxifen tablets twice a day every day and receive bortezomib by infusion into a vein on days 3, 6, 10, 13, 24, 27, 31 and 34. Treatment may continue as long as the tumor does not grow and the patient does not develop unacceptable side effects. In addition to drug treatment, patients undergo the following tests and procedures:

• Periodic routine blood tests.
• MRI or CT scan of the head before starting each new cycle. MRI uses a magnetic field and radio waves to produce images of body tissues and organs. CT uses x-rays to provide 3-dimensional views of the part of the body being studied. For both procedures, the patient lies on a table that slides into the cylindrical scanner.
• Blood test to measure levels of bortezomib. Blood is drawn before the bortezomib infusion on days 3 and 24, and 4 hours after the infusion on day 24 of the first treatment cycle only.
• Dynamic MRI with spectroscopy or positron emission tomography (PET). Patients may be asked to undergo one of these tests, which help distinguish live tumor from dying tumor. The experience of dynamic MRI with spectroscopy is the same as standard MRI and is done at the same time as the standard procedure (see above). PET uses a radioactive substance to show cellular activity in specific tissues of the body. The patient is given an injection of a sugar solution in which a radioactive isotope has been attached to the sugar molecule. A special camera detects the radiation emitted by the radioisotope, and the resulting images show how much glucose is being used in various parts of the body. Because rapidly growing cells, such as tumors, take up and use more glucose than normal cells do, this test can be used to show active tumors.
• Drug diary. Patients maintain a calendar to record when they take their study drugs and what side effects they develop.