Phase II trial of bevacizumab in combination with temozolomide and regional radiation therapy for up-front treatment of patients with newly diagnosed glioblastoma multiforme

2000

Background: Bevacizumab (BV) is a humanized monoclonal antibody directed against the vascular endothelial growth factor (VEGF). Based on the promising activity of BV in the treatment of recurrent glioblastoma, we are conducting a phase II trial to determine whether up-front treatment of newly diagnosed GBM with BV may be more advantageous than withholding BV until recurrence. In this trial, we evaluate the safety and efficacy of BV combined with standard of care radiation (RT) and temozolomide (TMZ) and radiation (RT) for newly-diagnosed GBM. Methods: This is a phase II trial with a 10-patient pilot and 60-patient expansion phases. Newly-diagnosed GBM patients with no prior treatments are eligible. Primary outcome measure is overall survival; the secondary outcome measure is TTP and 12-month survival. Therapy began between 3–5 weeks of surgery with BV (10 mg/kg every 2 weeks), TMZ (75 mg/m2 daily), and external beam RT (30 x 200 Gy) on the same day. After completion of radiation, patients are then placed on a maintenance phase of BV (10mg/kg every 2 weeks) and TMZ (150–200 mg/m2 5 out of every 28 days) until progression or 24 months in which patients are then maintained on BV only. Results: 70 of 70 projected GBM patients have been enrolled between August 2006 and November 2008 at UCLA and Kaiser Permanente (KP) (Northern and Southern California). All patients had resections to ensure that frozen tissue (>200mg) was collected. The median age was 57.4 years (range 31–75). MGMT methylation analysis has been performed on 52/70 patients with ∼40% showing methylation. Severe adverse events to date have included ischemic stroke, pulmonary embolus, wound breakdown, GI bleeding/perforation, and renal dysfunction. Isolated cases of retinal detachment and optic neuropathy have also been observed. As of now, 35/70 patients are off study (26 due to progression and 9 due to SAE). Preliminary TTP by Kaplan-Meier analysis is promising compared to that of a UCLA/KP control group of patients that received the conventional RT/TMZ regimen. Conclusions: Addition of BV to the standard regimen of TMZ and RT for newly-diagnosed GBM is well-tolerated and shows promising efficacy. More detailed analysis of safety and efficacy will presented.

[Table: see text]

Pilot study of modafinil for treatment of neurobehavioral dysfunction and fatigue in adult patients with brain tumors

1503

Background: Patients with brain cancer develop neurobehavioral dysfunction and fatigue that compromise their performance of daily activities. We report results from evaluating the efficacy and safety of modafinil treatment for tumor/therapy sequelae in this medically fragile patient population. Methods: Patients: 21–65 years old with primary malignant disease or nonmalignant cerebral tumors treated with neurosurgical resection, radiotherapy, and/or chemotherapy. Clinical Global Impression of Severity ratings of mild to severe attention/memory impairment and/or fatigue. Measures: Trail Making (TM) A and B, Symbol Digit Modalities (SDM), Verbal Fluency (VF), Hamilton Depression Scale (HAM-D), Fatigue Severity Scale (FSS), Visual Analogue Fatigue Scale (VAFS), Modified Fatigue Impact Scale (MFIS). Design: Double-blind dose-controlled randomization (200 or 400 mg/day modafinil in divided doses) 3 wks; Washout 1wk; Open label extension 8 wks. Statistical analyses: Changes from baseline at scheduled visits (1, 3, 4, 8, 12 wks) using paired t-tests or Wilcoxon Signed Rank tests as appropriate. Results: Thirty patients, 63% male, mean age (SD) = 45.3 (11.7) yrs were accrued from 6/03–10/05. Illness severity: moderate 3 (10%), marked 13 (43%), severe 14 (47%). Tumor histology: glioblastoma multiforme 8 (27%), anaplastic glioma 10 (33%), low grade glioma 10 (33%), meningioma 1 (3%), CNS lymphoma 1 (3%). Treatment: neurosurgical resection 93%, radiotherapy 87%, chemotherapy 70%. The table shows relationships of nine variables at baseline and 8 and 12 weeks after initiation of modafinil. Adverse events reported by ≥4 patients: headache 13 (42%); insomnia 8 (26%); dizziness 7 (23%); dry mouth 7 (23%); depressed consciousness 5 (16%); nausea 4 (13%). Conclusions: Results show improvement across cognitive, mood, and fatigue outcome measures. Modafinil was generally well tolerated, with a low incidence of adverse events. Greatest improvements in outcomes were observed 8 wks after baseline.

[Table: see text]

[Table: see text]

The 121 amino acid isoform of vascular endothelial growth factor is more strongly tumorigenic than other splice variants in vivo

Vascular endothelial growth factor (VEGF) is known to occur as at least six differentially spliced variants, giving rise to mature isoforms containing 121, 145, 165, 183, 189 and 206 amino acids. However, little is yet known concerning the in vivo activities of this differential splicing. Stably transfected MCF-7 breast carcinoma cells were constructed that secreted comparable amounts of the 121, 165 or 189 isoforms. Rabbit corneal angiogenesis assays showed the VEGF121 transfectant to have much greater angiogenic activity than the 165 or 189 expressing MCF-7 cells. While the VEGF121-expressing MCF-7 cells were reproducibly more tumorigenic than the control transfectants, this was not the case with the VEGF165- or VEGF189-expressing cells. More surprising was the observation that VEGF189 located to the nucleus, consistent with the presence of a highly conserved nuclear localization sequence in exon 6a that is expressed in VEGF189 but not 121 or 165. It was concluded that the VEGF121 isoform is both more angiogenic and tumorigenic than are the 165 and 189 isoforms. This is probably due to the ability of the 121 isoform, unlike the 165 and 189 isoforms, to freely diffuse from the cells producing it.