Vorinostat and Temozolomide in Treating Young Patients With Relapsed or Refractory Primary Brain Tumors or Spinal Cord Tumors

Inclusion Criteria:

* Histologically confirmed CNS malignancy at original diagnosis or relapse

  * Histologic confirmation not required for patients with intrinsic brain stem tumors, optic pathway gliomas, or pineal tumors provided CSF or serum tumor markers, including alpha-fetoprotein orbeta-HCG, are elevated
  * Recurrent or refractory spinal cord tumors allowed
* Measurable or evaluable disease
* No known curative therapy or therapy proven to prolong survival with an acceptable quality of life
* Karnofsky performance status (PS) 50-100% (for patients \> 16 years of age) OR Lansky PS 50-100% (for patients ≤ 16 years of age)

  * Neurological deficits must have been relatively stable for ≥ 1 week before study entry
  * Patients unable to walk due to paralysis, but who are up in a wheelchair, are considered ambulatory for the purpose of assessing performance status
* ANC ≥ 1,000/μL
* Platelet count ≥ 100,000/μL (transfusion independent, defined as no platelet transfusion within the past 7 days)
* Hemoglobin ≥ 8.0 g/dL (RBC transfusions allowed)
* Creatinine clearance or radioisotope GFR ≥ 70mL/min OR maximum serum creatinine based on age and/or gender as follows:

  * 0.6 mg/dL (1 year of age)
  * 0.8 mg/dL (2 to 5 years of age)
  * 1.0 mg/dL (6 to 9 years of age)
  * 1.2 mg/dL (10 to 12 years of age)
  * 1.5 mg/dL (males) or 1.4 mg/dL (females) (13 to 15 years of age)
  * 1.7 mg/dL (males) or 1.4 mg/dL (females) (≥ 16 years of age)
* Bilirubin ≤ 1.5 times upper limit of normal
* ALT ≤ 110 U/L
* Serum albumin ≥ 2 g/dL
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* Able to swallow capsules or liquid
* Seizure disorder allowed provided it is well controlled with nonenzyme-inducing anticonvulsants
* No pre-existing QTc ≥ 450 msec
* No uncontrolled infection
* No patients who, in the opinion of the investigator, may not be able to comply with the safety monitoring requirements of study
* Fully recovered from prior chemotherapy, immunotherapy, or radiotherapy
* More than 3 weeks since prior myelosuppressive chemotherapy (6 weeks for nitrosourea)
* At least 7 days since prior hematopoietic growth factors
* At least 7 days since prior biologic agent (antineoplastic agent)
* At least 7 days or 3 half-lives, whichever is longer, since prior monoclonal antibodies
* More than 2 weeks since prior local palliative radiotherapy (small port)
* At least 6 months since prior total-body radiotherapy (TBI), craniospinal radiotherapy, or radiotherapy to ≥ 50% of the pelvis
* At least 6 weeks since other prior substantial bone marrow radiotherapy
* At least 3 months since prior stem cell transplantation or rescue (without TBI)

  * No evidence of active graft-vs-host disease
* At least 2 weeks since prior valproic acid
* No prior vorinostat
* Prior temozolomide allowed provided there was no progressive disease during or within 1 month after completion of treatment
* Concurrent corticosteroids allowed provided patient has been on a stable or decreasing dose for ≥ 7 days before study entry
* No other concurrent investigational drugs
* No other concurrent anticancer agents, including chemotherapy, radiotherapy, immunotherapy, or biologic therapy
* No concurrent enzyme-inducing anticonvulsants