Erlotinib and Radiation Therapy in Treating Young Patients With Newly Diagnosed Glioma

• Number of Participants With Dose-limiting Toxicity (DLT) [ Time Frame: During the first 8 weeks of therapy ]
  DLT was defined as any of the following toxicities attributable to erlotinib therapy: thrombocytopenia grade 3 and 4; neutropenia grade 4; or any grade 3 and 4 non-hematologic toxicity except for grade 3 diarrhea and grade 3 nausea and vomiting lasting ≤48 hours in participants not receiving optimal supportive therapy, grade 3 skin rash, which did not affect normal daily activities, grade 3 fever or nonneutropenic infection, grade 3 seizures, grade 3 weight gain or loss, and grade 3 transaminase elevation that returned to grade 1 or baseline within 7 days. After enrollment of the first 4 participants, grade 3 and 4 electrolyte abnormalities that resolved to ≤grade 2 within 7 days were excluded as DLT. Toxicities were graded according to the Common Terminology Criteria for Adverse Events version 3.0.
  
  
• Maximum Tolerated Dose (MTD) of Erlotinib [ Time Frame: During the first 8 weeks of therapy. ]
  MTD was defined as the highest dosage level in which no more than one of six assessable participants experienced dose-limiting toxicities (DLT). The dosage of erlotinib was increased by approximately 30% in each dosage level starting at 80% of the MTD in adults with solid tumors. A traditional 3+3 dose escalation scheme was used to estimate the MTD.
  
  
• Progression Free Survival (PFS) [ Time Frame: 1 and 2 years after end of therapy ]

  Progression-free survival (PFS) distributions for the Phase II participants with anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM) were calculated using Kaplan-Meier estimates (n=41). PFS was defined as the interval between treatment start and initial failure, including clinical or radiologic progression or death from any cause.

  PFS was not calculated for the other disease types.

  
  

• Cmax of Erlotinib and Its Metabolite OSI-420 [ Time Frame: After first dose of therapy, and Day 8 of therapy ]
  Although the calculated dose of erlotinib was rounded to the nearest 25 mg, the actual dosage administered to patients was within 12% of the prescribed dosage in all but 1 patient. The latter patient received erlotinib at the lowest dosage level and the actual dosage was 19% higher than the calculated dose.
  
  
• Erlotinib Tmax [ Time Frame: After first dose of therapy ]
  Although the calculated dose of erlotinib was rounded to the nearest 25 mg, the actual dosage administered to patients was within 12% of the prescribed dosage in all but 1 patient. The latter patient received erlotinib at the lowest dosage level and the actual dosage was 19% higher than the calculated dose.
  
  
• AUC Time 0-infinite (AUCinf) of Erlotinib and Its Metabolite OSI-420 [ Time Frame: After first dose of therapy, and Day 8 of therapy ]
  Although the calculated dose of erlotinib was rounded to the nearest 25 mg, the actual dosage administered to patients was within 12% of the prescribed dosage in all but 1 patient. The latter patient received erlotinib at the lowest dosage level and the actual dosage was 19% higher than the calculated dose.
  
  
• Number of Positive Mutations of EGFR and Downstream Pathways [ Time Frame: Once at tumor resection and diagnosis ]

  Statistical analyses of genomic changes, expression profiles and validation studies should be considered in an exploratory and hypothesis-generating context.

  Fresh frozen tumor tissue was obtained at the time of tumor resection and diagnosis. DNA was extracted from formalin-fixed, paraffin-embedded tissue. The entire PTEN coding sequence (exons 1-9), exons 1, 9 and 20 of PIK3CA, and exons 17-24 of EGFR were evaluated using exon-specific PCR amplification, and immunohistochemistry was done. Tumor lesions were considered positive if >25% cells were immunoreactive.

  
  
• Ability of Erlotinib to Inhibit EGFR Signaling [ Time Frame: 5 Years ]

  The objective was to test the ability of erlotinib to inhibit the EGFR signaling in patients with high-grade glioma who required a second surgery.

  This outcome was not assessed due to insufficient availability of tumor and control samples for analysis.

  
  
• Correlation Between Standard Magnetic Resonance Imaging and Investigational Radiologic Techniques in Assessing Tumor Response to This Treatment [ Time Frame: at diagnosis and regular intervals during therapy (up to 2 years after start of therapy) ]
  This objective was to prospectively investigate the correlation between standard magnetic resonance imaging (MRI) and investigational radiologic techniques (MR spectroscopy, perfusion/diffusion, PET scan, DEMRI/BLAST) in assessing tumor response to this treatment.
  
  
• To Prospectively Investigate the Technical Factors Involved in Planning and Administering Conformal Fractionated RT as Outlined in This Study, and to Correlate RT Dosimetry With Patterns of Failure, Standard and Investigational Imaging and Toxicity [ Time Frame: 5 Years ]
  
• Plasma and CSF Levels of VEGF, bFGF, and SDF1 [ Time Frame: at diagnosis and regular intervals during therapy (up to 2 years after start of therapy) ]
  This objective was to determine the plasma and CSF levels of the VEGF, bFGF, and SDF1 at diagnosis, and the plasma levels of these factors at regular intervals during therapy, and to analyze the association of these results with tumor response.
  
  
• Number of Participants Experiencing Grade 3 or 4 Toxicity Events [ Time Frame: From start of therapy through 2 years. ]
  Adverse events were collected systematically for each of the 44 Phase II participants from the time of enrollment to the completion of therapy (approximately 2 years from start of therapy).
  
  

OBJECTIVES:

Primary

• Determine the maximum tolerated dose and dose-limiting toxicity of erlotinib when administered during and after radiotherapy in young patients with newly diagnosed high-grade glioma and unfavorable low-grade glioma.
• Determine the 1- and 2-year progression-free survival of patients treated with this regimen.

Secondary

• Determine the toxic effects of this regimen in these patients.
• Correlate genetic abnormalities in epidermal growth factor receptor (EGFR) and components of downstream pathways with treatment response in patients treated with this regimen.
• Determine the ability of erlotinib to inhibit EGFR signaling in patients with high-grade glioma who require second surgery.
• Determine the pharmacokinetics of erlotinib and its metabolites in these patients.
• Correlate plasma and cerebrospinal fluid levels of vascular endothelial growth factor and basic fibroblast growth factor with tumor response in patients treated with this regimen.
• Correlate irradiation dosimetry with patterns of failure, standard and investigational imaging, and toxicity in patients treated with this regimen.

OUTLINE: This is a phase I dose-escalation study of erlotinib followed by a phase II study.

• Phase I: Patients undergo radiotherapy once daily, 5 days week, for approximately 6½ weeks. Beginning on the first day of radiotherapy, patients receive oral erlotinib once daily for up to 2 years.

Cohorts of patients receive escalating doses of erlotinib until the maximum tolerated dose (MTD) is determined.

• Phase II: Patients will receive erlotinib as in phase I at the MTD and undergo radiotherapy as in phase I.

PROJECTED ACCRUAL: A total of 75-80 patients (15-20 for the phase I portion and 60 for the phase II portion) will be accrued for this study.