A Study of PD 0332991 in Patients With Recurrent Rb Positive Glioblastoma

This study will determine the efficacy of the small molecule CDK4/6 inhibitor PD 0332991 (as measured by progression free survival at 6 months) in patients with recurrent glioblastoma multiforme or gliosarcoma who are Rb positive. A total of 30 patients will be treated; 15 will undergo a planned surgical resection and receive drug for 7 days prior to surgery, followed by drug after recovery from surgery, and the other 15 patients will receive drug without a planned surgical procedure.

A total of 30 patients with recurrent Glioblastoma or Gliosarcoma will be treated with PD 0332991 at a dose of 125 mg daily for 21 consecutive days followed by a 7 day break off therapy (cycle length is 28 days). Of these 30 patients, 15 will receive drug for 7 days prior to an indicated, intended surgical resection for progression, and will then resume drug at the same dose after recovery from surgery. Treatment will be repeated every 28 days, and in the absence of disease progression patients may receive treatment for 12 cycles. At that time patients will be given the option to continue on study past 12 cycles, up to a maximum of 24 cycles. Following registration, available blocks or slides from a previous surgery must be submitted for diagnosis review (confirmation of Glioblastoma multiforme or Gliosarcoma) and Rb status determination. Only patients with Rb positive tumors can be treated, and Rb tumor status must be known prior to any treatment. Additional tissue from previous surgeries will also be obtained to evaluate molecular abnormalities in the tumor. These studies will be done retrospectively and are not required to be performed prior to registration. Monitoring will include a clinical and neurological exam before the beginning of each cycle (every 4 weeks). Complete blood counts with differential will be examined on days 1 and 15 of each cycle. Liver and renal function will be performed every 4 weeks. Toxicity and dose modifications will be based on the NCI CTCAE Version 4. Disease status will be assessed clinically each cycle (every 4 weeks) and radiographically after each second cycle (every 8 weeks).