Bevacizumab and Irinotecan in Treating Young Patients With Recurrent, Progressive, or Refractory Glioma, Medulloblastoma, Ependymoma, or Low Grade Glioma

• Objective Response Rate Sustained for ≥ 8 Weeks [ Time Frame: From day 1 of treatment up to 24 weeks ]
  Objective response is either a complete response or a partial response observed during the first four courses of treatment and sustained for 8 weeks. The objective response rate will be reported separately for patients with recurrent/progressive malignant glioma(Stratum A), recurrent/progressive instrinsic brain stem tumors(Stratum B), recurrent/progressive medulloblastoma(Stratum C), and recurrent/progressive ependymoma(Stratum D). CR is complete disappearance of all enhancing tumor. PR is >= 50% reduction in tumor size. This outcome measures is not defined for the Stratum E in the protocol.
  
  
• Sustained Disease Stabilization Rate Associated With Bevacizumab and Irinotecan in Patients With Recurrent or Progressive Low-grade Glioma (Stratum E) [ Time Frame: From day 1 of treatment up to 24 weeks ]
  Disease stabilization is defined as a complete response(CR) or partial response(PR) observed during the first four courses and sustained for 8 weeks; or stable disease (SD) sustained for 6 courses characterized by SD at the end of course 2, at the end of course 4 and at the end of course 6. CR is complete disappearance of all enhancing tumor. PR is >= 50% reduction in tumor size. SD is at least stable and maintenance corticosteroid dose not increased in neurologic examination.
  
  

• Number of Study Participants With Grade 3 or 4 Treatment-related Toxicity [ Time Frame: From day 1 of treatment until off study ]
  Adverse events are monitored and graded according to the Common Terminology Criteria for Adverse Events. The grade 1 = mild, grade 2=moderate, grade 3 =severe, grade 4=life threatening/disabling, grade 5=death.
  
  
• Cumulative Incidence of Sustained Objective Responses [ Time Frame: From the first imaging after treatment up to 2 years ]
  Cumulative incidence of sustained objective response provides a percentage of participants experiencing the event of interest at a given follow-up time point (for example, 6-months, 1-year, etc.) in the presence of competing events such as progressive disease or death, and it is estimated using the event data for both the event of interest and the competing events experienced by the study participants. In this sense, it is different than the incidence rates estimated in epidemiological studies in terms of 'incidences per 1000 person years. 6-month Cumulative incidence of sustained objective responses will be reported separately for each stratum.
  
  
• Progression-free Survival [ Time Frame: From start of treatment up to 2 years ]
  Progression-Free survival is the interval of time between of protocol treatment and minimum date of documentation of progressive Disease,second malignancy,death due to any cause, or date of last follow-up. Progressive neurologic abnormalities or worsening neurologic status not explained by causes unrelated to tumor progression,OR the appearance of new tumor OR a > 25% increase in the sum of the products of two longest perpendicular diameters of all measurable tumors. K-M method was used to estimate progression-free survival.
  
  
• Change in Perfusion Ratio Between the Baseline and Day 15 Brain Imaging [ Time Frame: Baseline and day 15 ]

  Perfusion ratio obtained from magnetic resonance(MR) diffusion imaging may explain changes in the tumor after therapy. Changes in the perfusion ratio will be reported for those strata that have a sufficient number of participants with MR diffusion imaging. The change was calculated from perfusion ratio at Baseline to perfusion ratio at Day 15(values of perfusion ratio at Day 15 - values of perfusion ratio at baseline). The higher of perfusion ratio is worse.

  MR perfusion ratio is perfusion solid part of tumor from CBV divided by perfusion frontal while matter. There is no a unit available.

  
  
• Change in Diffusion Ratio Between the Baseline and Day 15 Brain Image [ Time Frame: Baseline and day 15 ]
  Diffusion ratio obtained from magnetic resonance (MR) diffusion imaging may explain changes in the tumor after therapy. Changes in the diffusion ratio will be reported for those strata that have a sufficient number of participants with MR diffusion imaging. The change was calculated from diffusion ratio at Baseline to diffusion ratio at Day 15 (values of diffusion ratio at Day 15 -values of diffusion ration at baseline). The higher of diffusion ratio is better. MR diffusion ratio is the diffusion solid part of tumor divided by the diffusion frontal white matter. There is no a unit available.
  
  
• Association of Log-transformed Tumor Volume Based on FLAIR With Progression-free Survival (PFS) Using Hazard Ratio Estimates [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study OR up to 2 years ]
  Using Cox proportional hazards models, the association of tumor volume based on FLAIR images with PFS will be investigated for those strata that have a sufficient number of participants with volume FLAIR measurements. Volumetric magnetic resonance imaging is performed to investigate surrogate markers of tumor growth. Volume FLAIR measurements were longitudinal. As we are not comparing the strata, analyses will be done in each stratum separately, and thus we cannot report the Cox model results in the Statistical Analysis section. We consider these estimates 'descriptive' within each stratum. In this analysis, the hazard ratio is a relative measure of likelihood that a study participant experiences the event of interest compared to another participant who has a one-unit lower Log-transformed tumor volume based on FLAIR. The Cox survival model provides the mean hazard ratio along with its 95% confidence interval, which we report below.
  
  
• Association of Log-transformed Tumor Enhancing Volume With Progression-free Survival (PFS) Using Hazard Ratio Estimates [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study, OR up to 2 years ]
  Using Cox Proportional hazards Models, the association of Log-transformed tumor enhancing volume with progression-free survival will be investigated. Volumetric magnetic resonance (MR) imaging is performed to investigate surrogate markers of tumor growth. Tumor enhancing volumes were longitudinal. As we are not comparing the strata or study arms, analyses will be done in each stratum separately, and thus we cannot report the Cox model results in the Statistical Analysis section and we consider these estimates 'descriptive' within each stratum. In this analysis, the hazard ratio is a relative measure of likelihood that a study participant experiences the event of interest compared to another participant who has a one-unit lower Log-transformed tumor enhancing volume. The Cox survival model provides the mean hazard ratio along with its 95% confidence interval, which we report below.
  
  
• Association of Log-transformed Volume of Cystic Necrosis With Progression-free Survival (PFS) Using Hazard Ratio Estimates [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study, OR up to 2 years ]
  Using Cox Proportional Hazards Models, the association of cystic necrosis with progression-free survival will be investigated. Volumetric magnetic resonance (MR) imaging is performed to investigate surrogate markers of tumor growth. Volumes of cystic necrosis were longitudinal. As we are not comparing the strata or study arms, analyses will be done in each stratum separately, and thus we cannot report the Cox model results in the Statistical Analysis section and we consider these estimates 'descriptive' within each stratum. In this analysis, the hazard ratio is a relative measure of likelihood that a study participant experiences the event of interest compared to another participant who has a one-unit lower Log-transformed tumor volume based on cystic necrosis. The Cox survival model provides the mean hazard ratio along with its 95% confidence interval, which we report below.
  
  
• Association of Log-transformed Tumor Diffusion Ratio With Progression-free Survival (PFS) Using Hazard Ratio Estimates [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study ]
  Using Cox Proportional Hazards Models, the association of tumor diffusion ratios with progression-free survival will be investigated. Magnetic resonance (MR) diffusion imaging is performed to investigate surrogate markers of tumor growth. Tumor diffusion ratios were longitudinal. As we are not comparing the strata or study arms, analyses will be done in each stratum separately, and thus we cannot report the Cox model results in the Statistical Analysis section. And we consider these estimates 'descriptive' within each stratum. In this analysis, the hazard ratio is a relative measure of likelihood that a study participant experiences the event of interest compared to another participant who has a one-unit lower Log-transformed tumor diffusion ratio. The Cox survival model provides the mean hazard ratio along with its 95% confidence interval, which we report below.
  
  
• Association of Log-transformed Tumor Perfusion Ratio With Progression-free Survival (PFS) Using Hazard Ratio Estimates [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study, OR up to 2 years ]
  Using Cox Proportional Hazards Models, the association of tumor perfusion ratio with progression-free survival will be investigated. Magnetic resonance (MR) perfusion imaging is performed to investigate surrogate markers of tumor growth. Tumor perfusion ratios were longitudinal. As we are not comparing the strata or study arms, analyses will be done in each stratum separately, and thus we cannot report the Cox model results in the Statistical Analysis section. We consider these estimates 'descriptive' within each stratum. In this analysis, the hazard ratio is a relative measure of likelihood that a study participant experiences the event of interest compared to another participant who has a one-unit lower Log-transformed tumor volume perfusion ratio. The Cox survival model provides the mean hazard ratio along with its 95% confidence interval, which we report below.
  
  
• Volume of Distribution [ Time Frame: Baseline, Course 1 Day 1, Course 1 Day 15, Course 2 Day 1, Course 3 Day 1, Course 4 Day 1, and Course 5 Day 1 ]
  Blood specimens will be collected on the days listed for pharmacokinetic studies for Bevacizumab. These specimens will be analyzed to produce steady-state plasma Bevacizumab concentration-time data in study participants. The concentration-time data will be analyzed to provide an estimate of the volume of distribution. Estimates of the volume of distribution will be reported separately for each stratum.
  
  
• Systemic Clearance [ Time Frame: Baseline, Course 1 Day 1, Course 1 Day 15, Course 2 Day 1, Course 3 Day 1, Course 4 Day 1, and Course 5 Day 1 ]
  Blood specimens will be collected on the days listed for pharmacokinetic studies for Bevacizumab. These specimens will be analyzed to produce steady-state plasma Bevacizumab concentration-time data in study participants. The concentration-time data will be analyzed to provide an estimate of the systemic clearance. Estimates of the systemic clearance will be reported separately for each stratum.
  
  
• Terminal Half-life [ Time Frame: Baseline, Course 1 Day 1, Course 1 Day 15, Course 2 Day 1, Course 3 Day 1, Course 4 Day 1, and Course 5 Day 1 ]
  Blood specimens will be collected on the days listed for pharmacokinetic studies for Bevacizumab. These specimens will be analyzed to produce steady-state plasma Bevacizumab concentration-time data in study participants. The concentration-time data will be analyzed to provide an estimate of the terminal half-life. Estimates of the terminal half-life will be reported separately for each stratum.
  
  
• Change in Vascular Endothelial Growth Factor Receptor-2 (VEGF-R2) Expression in Peripheral Blood Mononuclear Cells (PBMC) From Baseline to Day-15 [ Time Frame: Baseline and 24-48 hours after the 2nd dose of Bevacizumab in course 1 ]
  The change in VEGF-R2 was calculated from baseline to the time of the 2nd dose (values of 24-48 hours after the 2nd dose at Day 15 - values of pre-dose 1 Day1, i.e., baseline). VEGF-R2 is measured in the relative phosphorylation score which is generated as a ratio of normalized phosphorylated VEGF-R2 versus normalized total VEGF-R2 protein.
  
  
• Descriptive Statistics for the Changes in Vascular Endothelial Growth Factor Receptor-2 (VEGF-R2) Expression in Peripheral Blood Mononuclear Cells (PBMC) Concurrently Measured With the Changes in Perfusion From Magnetic Resonance Imaging [ Time Frame: Baseline and Day 15 (after 2 doses of Bevacizumab) of course 1 ]
  The changes in VEGF-R2 are calculated by values at Day 15 minus values at baseline for the patients who had the changes in perfusion from magnetic resonance perfusion imaging. The purpose of reporting descriptive statistics of changes of VEGF-R2 is to provide the information for the correlation coefficients in Section 19.
  
  
• Descriptive Statistics for the Change of Perfusion in Magnetic Resonance Imaging Concurrently Measured With the Change in Vascular Endothelial Growth Factor Receptor-2 (VEGF-R2) Expression in Peripheral Blood Mononuclear Cells (PBMC) [ Time Frame: Baseline and Day 15 (after 2 doses of Bevacizumab) of course 1 ]
  The change of perfusion in magnetic resonance imaging is calculated by taking the difference between the Day-15 measurements and the Baseline measurements for patients who had the changes of VEGF-R2. The purpose of reporting the descriptive statistics is to provide the information for the correlation coefficients reported in the next section, Section 19. MR perfusion ratio is the ratio of the perfusion measurements in the tumor and the perfusion measurerement in comparative frontal while matter, which is the comparative healthy part of the brain.
  
  
• Correlation of the Change in Vascular Endothelial Growth Factor Receptor-2 (VEGF-R2) Expression in Peripheral Blood Mononuclear Cells (PBMC) From Baseline With the Change in Perfusion From Magnetic Resonance Imaging [ Time Frame: Baseline and Day 15 (after 2 doses of Bevacizumab) of course 1 ]
  Spearman correlation coefficient is used to measure the correlation of the changes in VEGF-R2 with the changes in perfusion ratios. The changes are calculated by values at Day 15 minus values at baseline for VEGF-2 in Section 17 above and perfusion in Section 18 above, respectively. The correlation coefficients are reported in each stratum separately.
  
  
• Number of Patients With High Hypoxia Inducible Factor-2alpha Expression at Baseline [ Time Frame: Baseline ]
  Reported separately for each stratum.
  
  
• Number of Patients With High Carbonic Anhydrase 9 Expression at Baseline [ Time Frame: Baseline ]
  Reported separately for each stratum.
  
  
• Number of Patients With High VEGF-A Expression at Baseline [ Time Frame: Baseline ]
  Reported separately for each stratum.
  
  
• Number of Patients With High VEGF-R2 Expression at Baseline [ Time Frame: Baseline ]
  Reported separately for each stratum.
  
  
• Progression-free Survival Hazard Ratio by Hypoxia Inducible Factor-2alpha Expression [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study ]
  The association of hypoxia inducible factor-2alpha expression with progression-free survival will be investigated for those strata that have a sufficient number of participants with hypoxia inducible factor-2alpha measurements.
  
  
• Progression-free Survival Hazard Ratio by Carbonic Anhydrase 9 (CA9) Expression [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study ]
  The association of CA9 expression with progression-free survival will be investigated for those strata that have a sufficient number of participants with CA9 measurements.
  
  
• Progression-free Survival Hazard Ratio by VEGF-A Expression [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study ]
  The association of VEGF-A expression with progression-free survival will be investigated for those strata that have a sufficient number of participants with VEGF-A measurements.
  
  
• Progression-free Survival Hazard Ratio by VEGF-R2 Expression [ Time Frame: From start of treatment until the earliest of progressive disease, death, second malignancy or off study ]
  The association of VEGF-R2 expression with progression-free survival will be investigated for those strata that have a sufficient number of participants with VEGF-R2 measurements.
  
  

PRIMARY OBJECTIVES:

I. Estimate the rates of objective response observed prior to disease progression during the first four courses of treatment with bevacizumab and irinotecan hydrochloride in pediatric patients with recurrent, progressive, or refractory malignant glioma (Stratum A [closed to accrual as of 4/21/2009]) or recurrent/progressive/refractory intrinsic brain stem glioma (Stratum B [closed to accrual as of 4/21/2009]).

II. Estimate the rates of objective response observed prior to disease progression during the first four courses of treatment with bevacizumab and irinotecan hydrochloride in patients with recurrent or progressive medulloblastoma (Stratum C [closed to accrual as of 10/27/2009]) or recurrent or progressive ependymoma (Stratum D [closed to accrual as of 7/29/2010]).

III. Estimate the sustained disease stabilization rate associated with bevacizumab and irinotecan in patients with recurrent or progressive low grade glioma (Stratum E [closed to accrual as of 7/29/2010]).

SECONDARY OBJECTIVES:

I. Estimate the rate of treatment-related toxicity of this regimen in these patients.

II. Estimate the cumulative incidence of sustained objective responses as a function of this regimen in these patients.

III. Estimate the distributions of survival and event-free survival of these patients.

IV. Correlate functional changes in tumor with progression-free survival and response using MR perfusion/diffusion imaging and fludeoxyglucose F 18 positron emission tomography.

OUTLINE: This is a multicenter study. Patients are stratified according to tumor type (high-grade glioma [closed to accrual as of 4/21/2009] vs intrinsic brain stem tumor [closed to accrual as of 4/21/2009] vs medulloblastoma [closed to accrual as of 10/27/2010] vs ependymoma [closed to accrual as of 7/29/2010] vs low grade glioma [closed to accrual as of 7/29/2010]).

Patients receive bevacizumab IV over 30-90 minutes on days 1 and 15 and irinotecan hydrochloride IV over 90 minutes on day 16 or 17 for course 1. Patients receive bevacizumab and irinotecan hydrochloride on days 1 and 15 for all subsequent courses. Treatment repeats every 4 weeks for up to 24 courses in the absence of disease progression or unacceptable toxicity.

Patients undergo MRIs of the brain, magnetic resonance perfusion/diffusion, and fludeoxyglucose F 18 positron emission tomography at baseline and periodically during treatment.

After completion of study treatment, patients are followed for 30 days and then every 3 months for up to 2 years.