Inclusion Criteria:

- Histologically confirmed diagnosis of a primary malignant brain tumor or, if
metastatic, documentation and histology (if available) of primary source of cancer.

- Patient must have 1 or more qualifying steroid-associated side effect(s) at Baseline.

- Patient has required administration of dexamethasone to control symptoms of
peritumoral edema for at least 30 days.

- Stable dexamethasone dose of 4-24 mg/day for at least 14 days prior to Baseline.

- Need for administration of dexamethasone to treat peritumoral brain edema (referenced
above) has been documented by MRI or comparable diagnostic technology within 21 days
of Baseline.

- Karnofsky score of > 50 at Screening and Baseline.

- Capable of self-administration of subcutaneous injections twice daily for 12 weeks,
or availability of assistance from caregiver.

- Ability to provide written informed consent or, if unable to provide, have a legal
guardian or representative provide written informed consent.

- For women of childbearing potential: a negative serum pregnancy test at Screening.

- Must be 18 years of age or older

Exclusion Criteria:

- Ongoing or anticipated need for surgery, radiosurgery or radiation therapy or the
introduction of new chemotherapeutic regime within the first 5 weeks of study
enrollment. Treatment with pre-study chemotherapy may continue.

- Concurrent enrollment in any other investigational drug or device study, or plan to
enroll in such a study during the first 5 weeks of treatment.

- Systemic steroid use for any indication other than peritumoral brain edema.

- Use or intended use of dexamethasone as an anti-emetic during Screening or Study

- Non-compliance with dexamethasone or anticonvulsant therapy.

- Clinical signs and symptoms of cerebral herniation.

- Serious concomitant cardiovascular, pulmonary, renal, gastrointestinal or endocrine
metabolic disease which could put the patient at unusual risk for study
participation.

- Confounding previous or concurrent neurological disorders that would interfere with
adequate clinical evaluation.

- Clinically significant head injury or chronic seizure disorder, if the condition
results in functional impairment or is likely to interfere with evaluations.
(Maintenance anticonvulsant therapy is allowed.)

- Central nervous system infection.

- Pregnancy, breastfeeding and/or refusal to practice birth control while in study, for
women of childbearing potential.

- Any conditions that are considered contraindications for patients to receive niacin,
e.g. liver disease (with LFTs > 3 times the upper limit of the norm),active peptic
ulcer, arterial hemorrhage, asthma and known hypersensitivity to niacin.