This is a multi-center, multinational phase 2 trial that aims to explore the use of molecular and clinical risk-directed therapy in treatment of children 0-4.99 years of age with newly diagnosed medulloblastoma.
The objectives of this study are: Primary Objectives * To estimate the progression free survival of SHH-2 infant (0-2.99 years) and young child (3-4.99 years) medulloblastoma patients treated with systemic HD-MTX- based chemotherapy only. * To estimate the progression free survival of SHH-1 infant (0-2.99 years) medulloblastoma patients treated with systemic HD-MTX-based chemotherapy augmented with IVT-MTX. * To estimate the progression free survival of G3/G4 infant (0-2.99 years) medulloblastoma patients treated with systemic chemotherapy and delayed risk- adapted CSI augmented with carboplatin. * To compare cognitive outcomes among infants (0-2.99 years) and young children (3-4.99 years) treated with systemic chemotherapy only to patients treated with systemic chemotherapy and intra-ventricular chemotherapy or delayed risk- adapted craniospinal irradiation. Secondary Objectives * To investigate change in neurocognitive performance among infants (0-2.99 years) and young children (3-4.99 years) treated for medulloblastoma, and examine the impact of demographic factors (e.g., age at treatment, gender, and socioeconomic status), disease-related factors (e.g., presence of hydrocephalus, posterior fossa syndrome) and variants of proposed treatment regimen (e.g., systemic chemotherapy with or without IVT-MTX, radiation dosimetry to key brain structures, treatment-related ototoxicity) on cognitive late effects. * To investigate which familial factors (e.g., family cohesion, family coping with medical management, parent-child interaction style) and environmental factors (e.g., parental verbal abilities, home literacy, adherence with rehabilitative therapies, participation in early intervention, school advocacy) associate with socioeconomic status and examine the impact of these factors on cognitive late effects. * To evaluate the feasibility and acceptability of a caregiver education program paired with interactive neurodevelopmental games used to improve parent-child interactions, cognitive and social-emotional functioning in infants undergoing treatment for medulloblastoma. (funded by NCI via the R21CA280187) * To estimate the magnitude of change in parent-child interactions following participation in a caregiver education paired with interactive neurodevelopmental games. (funded by NCI via the R21CA280187) * To estimate the magnitude of change in cognition and social-emotional development associated with a caregiver education program combined with interactive neurodevelopmental games. (funded by NCI via the R21CA280187) * To determine the extent of inter- and intra-patient variability in the plasma pharmacokinetics of high-dose systemic methotrexate, cyclophosphamide, vincristine, and topotecan in infants and young children with medulloblastoma, to assess potential covariates to explain this variability, and to explore associations between clinical effects and methotrexate, cyclophosphamide, vincristine, and topotecan pharmacokinetics. * To determine the extent of inter- and intra-patient pharmacokinetic variability of methotrexate in ventricular CSF after intraventricular methotrexate dose administration in infants with medulloblastoma, and to explore associations between methotrexate CSF pharmacokinetics and clinical effects. All participants enrolled will be treated with systemic chemotherapy post-surgical resection of the tumor. Participants will be assigned to treatment strata based first on tumor molecular group and subgroup assignment \[SHH (including SHH-1, SHH-2, SHH-3, SHH-4 and SHH-NOS), G3, G4, (including NWNS NOS, or indeterminate cases\] and then by clinical risk stratification (age and metastatic state). Infants and young children on Stratum S-2 and infants on Stratum S-1 will be treated with chemotherapy-only strategies. * Stratum S-2: Patients on S-2 will receive 8 courses of chemotherapy consisting of: * 4 Course A (A1A2A3A4) * 2 Course B (B1B2) * 2 Course C (C1C2) Courses repeat every 28 days/4 weeks. * Stratum S-1: Patients on S-1 will receive the same systemic chemotherapy regimen as S-2, with the addition of intraventricular (IVT)- MTX, administered via Ommaya reservoir, with each systemic MTX infusion. Each S-1 patient is scheduled to receive 12 doses of IVT-MTX. Each patient on S-1 will also receive 8 courses of combination chemotherapy. (4 Course A with IVT, 2 Course B with IVT and 2 Course C). Courses repeat every 28 days/4 weeks. * Stratum N: Stratum N participants will be treated with post-surgery chemotherapy until 36-months-of age followed by radiation CSI with Boost. There is no defined maximum number of systemic chemotherapy courses in stratum N. The length of chemotherapy (number of courses) will depend on the patient's age at enrollment. The chemotherapy plan for stratum N is divided into 5 sub-cohorts: * Age ≥34 months and \< 36 months: 4 cycles - 2 cycles (A1A2) prior to radiation and 2 cycles (E1, E2) post-radiation * Age: ≥32 to \<34 months-old: 4 cycles (A1A2A3A4) * Age: ≥30 to \<32 months-old: 6 cycles (A1A2A3A4 B1B2) * Age: ≥28 to \<30-months-old: 8 cycles (A1A2A3A4 B1B2 C1C2) * Age: \< 28 months-old: 8 cycles + multiple cycles of Course D until 36 months old (A1A2A3A4 B1B2 C1C2 D1D2D3D4…) Courses A, B, C and E repeat every 28 days/4 weeks and Course D repeats every 42 days. Prior to radiation therapy, around when stratum N patients achieve 36 months of age, they will be re-stratified onto substratum N-1, N-2 or N-3 based on their response to chemotherapy. Patients who receive less than or equal to 4 cycles of systemic chemotherapy prior to CSI regardless of their substratum assignment (N-1, N-2 or N-3) will have their radiation therapy augmented by IV carboplatin. Carboplatin will be given to each of these patients 1-4 hours before each radiation fraction is delivered. Patients enrolled in stratum N who have received only 2 courses of pre-radiation chemotherapy will receive 2 additional courses of adjuvant chemotherapy after completing CSI . The adjuvant chemotherapy consists of Cisplatin, Cyclophosphamide, and Vincristine. Patients who receive equal to 4 courses of systemic chemotherapy prior to CSI will have their radiation therapy augmented by IV carboplatin. The patients receiving more than 4 courses of chemotherapy prior to radiation will not receive additional adjuvant chemotherapy after completing CSI. Patients will be followed for 84 months following enrollment.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
130
All participants enrolled will undergo surgical resection prior to treatment. The maximal resection that can be achieved without undue risk to the patient will be attempted, with decisions about feasibility and extent of resection left to the discretion of the neurosurgeon. In instances where an STR is the best extent of resection achieved prior to start of therapy, a "second-look" surgery may be performed between cycles of chemotherapy after discussion with the principal investigator.
All participants enrolled on S-1 will undergo
Route of administration: Intravenously (IV)
Lucille Packard Children's Hospital Stanford
Palo Alto, California, United States
RECRUITINGOrlando Health Arnold Palmer Hospital for Children
Orlando, Florida, United States
RECRUITINGProgression free survival of SHH-2 infant (0-2.99 years) and young child (3-4.99 years) medulloblastoma patients treated with systemic HD-MTX-based chemotherapy only.
Progression free survival (PFS) will be measured from treatment initiation to the earliest of disease progression or death from any cause in stratum S-2 eligible M0 patients who receive at least 1 dose of the chemotherapy regimen. Patients who have not experienced one of these events will be censored at their last date of contact. The Kaplan-Meier estimate of PFS at two years will be computed. PFS will be compared to St. Jude historical cohorts using hazard ratios with 95% confidence intervals.
Time frame: Up to 7 years after enrollment with PFS estimation occurring 2 years after treatment initiation of last patient
Progression free survival of SHH-1 infant (0-2.99 years) medulloblastoma patients treated with systemic HD-MTX-based chemotherapy augmented with IVT-MTX.
Progression free survival (PFS) will be measured from treatment initiation to the earliest of disease progression or death from any cause in stratum S-1 eligible SHH-1 patients who receive at least 1 dose of the chemotherapy regimen. Patients who have not experienced one of these events will be censored at their last date of contact. The Kaplan-Meier estimate of PFS at two years will be computed. PFS will be compared to St. Jude historical cohorts using hazard ratios with 95% confidence intervals.
Time frame: Up to 7 years after enrollment with PFS estimation occurring 2 years after treatment initiation of last patient
Progression free survival of G3/G4 infant (0-2.99 years) medulloblastoma patients treated with systemic chemotherapy and delayed risk-adapted CSI augmented with carboplatin.
Progression free survival (PFS) will be measured from treatment initiation to the earliest of disease progression or death from any cause in stratum S-N eligible patients who receive at least 1 dose of the chemotherapy regimen. Patients who have not experienced one of these events will be censored at their last date of contact. The Kaplan-Meier estimate of PFS at two years will be computed. PFS will be compared to St. Jude historical cohorts using hazard ratios with 95% confidence intervals.
Time frame: Up to 7 years after enrollment with PFS estimation occurring 2 years after treatment initiation of last patient
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Route of administration: Intravenously (IV)
Route of administration: Intravenously (IV)
Route of administration: Intravenously (IV)
Route of administration: Intravenously (IV)
Route of administration: Intravenously (IV)
Route of administration: Intravenously (IV)
Route of administration: subcutaneous (SQ)
Route of administration: subcutaneous (SQ) or Intravenously (IV)
All participants in stratum N will undergo craniospinal irradiation (CSI) with boost to the primary tumor site once they reach 36 months of age. The dose given is based on the molecular risk group and disease response to chemotherapy as noted in the arm descriptions. The type of radiation used includes conformal radiation therapy (photons) or intensity modulated radiation therapy (IMRT) or proton beam therapy.
Participants watch a 75-minute caregiver education video program and receive access to interactive games on a smartphone or tablet throughout the optional cognitive study.
Standard-of-care (SOC) treatment during main cognitive study. After the one-year serial cognitive evaluation, participants will be offered participation in the cognitive study group I intervention.
Route of administration: Intravenously (IV) \& Intra Ventricular (IVT)
St. Joseph's Children's Hospital
Tampa, Florida, United States
RECRUITINGC.S. MOTT Children's Hospital, University of Michigan
Ann Arbor, Michigan, United States
RECRUITINGChildren's Hospital and Clinics of Minnesota
Minneapolis, Minnesota, United States
RECRUITINGSt. Jude Children's Research Hospital
Memphis, Tennessee, United States
RECRUITINGUT Southwestern Medical Center/Harold C Simmons Comprehensive Cancer Center
Dallas, Texas, United States
RECRUITINGCook Children's Medical Center
Fort Worth, Texas, United States
RECRUITINGTexas Children's Hospital
Houston, Texas, United States
RECRUITINGPrimary Children's Hospital
Salt Lake City, Utah, United States
RECRUITINGIQ among infants and young children treated with systemic chemotherapy only compared to patients treated with systemic chemotherapy and intra-ventricular chemotherapy or delayed risk-adapted craniospinal irradiation
Change from baseline over time in intellectual function (IQ) will be assessed using different instruments as age appropriate. IQ will be measured in children 0-3:6 years of age using Bayley Scales of Infant and Toddler Development, Fourth Edition (Bayley-4), in children 3.0-5.11 years of age using Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV), and in children 6-10 years of age using Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V). Longitudinal analyses will be conducted using mixed models.
Time frame: Baseline through 5 years after enrollment
Executive function among infants and young children treated with systemic chemotherapy only compared to patients treated with systemic chemotherapy and intra-ventricular chemotherapy or delayed risk-adapted craniospinal irradiation
Change from baseline over time in executive functions will be assessed using different instruments as age appropriate. The Behavior Rating Inventory of Executive Function \[BRIEF-P (ages 2-5:11) and BRIEF-2 (ages 6-18)\] will assess behavioral manifestations of executive function. Longitudinal analyses will be conducted using mixed models.
Time frame: Baseline through 5 years after enrollment
Health-related quality of life among infants and young children treated with systemic chemotherapy only compared to patients treated with systemic chemotherapy and intra-ventricular chemotherapy or delayed risk-adapted craniospinal irradiation
Changes from baseline over time in health-related quality of life will be assessed using the PedsQL (ages 2 and older). Longitudinal analyses will be conducted using mixed models.
Time frame: Baseline through 5 years after enrollment
Change in IQ among infants (0-2.99 years) and young children (3-4.99 years) treated for medulloblastoma
IQ will be assessed using different instruments as age appropriate. IQ will be measured in children 0-3:6 years of age using Bayley Scales of Infant and Toddler Development, Fourth Edition (Bayley-4), in children 3.0-5.11 years of age using Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV), and in children 6-10 years of age using Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V). The multiple instruments will be combined across all ages into one measure of standardized Full-Scale IQ. A linear mixed-effects regression model will be used to examine changes in IQ from baseline over time as related to demographic (e.g., age at treatment, gender, and socioeconomic status), disease-related (e.g., presence of hydrocephalus, posterior fossa syndrome), and treatment (e.g., systemic chemotherapy with or without IVT-MTX, radiation dosimetry to key brain structures, treatment-related ototoxicity) factors.
Time frame: Baseline through 5 years after enrollment
Change in executive function among infants (0-2.99 years) and young children (3-4.99 years) treated for medulloblastoma
This will be assessed using different instruments as age appropriate (The Behavior Rating Inventory of Executive Function \[BRIEF-P (ages 2-5:11) and BRIEF-2 (ages 6-10)\] will assess behavioral manifestations of executive function. A linear mixed-effects regression model will be used to examine changes in executive function from baseline over time as related to demographic (e.g., age at treatment, gender, and socioeconomic status), disease-related (e.g., presence of hydrocephalus, posterior fossa syndrome), and treatment (e.g., systemic chemotherapy with or without IVT-MTX, radiation dosimetry to key brain structures, treatment-related ototoxicity) factors.
Time frame: Baseline through 5 years after enrollment
Change in health-related quality of life among infants (0-2.99 years) and young children (3-4.99 years) treated for medulloblastoma
Health-related quality of life will be assessed using the PedsQL (ages 2 and older). A linear mixed-effects regression model will be used to examine changes in health-related quality of life from baseline over time as related to demographic (e.g., age at treatment, gender, and socioeconomic status), disease-related (e.g., presence of hydrocephalus, posterior fossa syndrome), and treatment (e.g., systemic chemotherapy with or without IVT-MTX, radiation dosimetry to key brain structures, treatment-related ototoxicity) factors.
Time frame: Baseline through 5 years after enrollment
Association of familial factors and environmental factors with socioeconomic status
Socioeconomic status will be measured using the Barratt Simplified Measure of Social Status (BSMSS). Generalized linear models will be used to investigate the association of socioeconomic status with familial factors (e.g., family cohesion, family coping with medical management, parent-child interaction style) and environmental factors (e.g., parental verbal abilities, home literacy, adherence with rehabilitative therapies, participation in early intervention, school advocacy)
Time frame: Baseline through 5 years after enrollment
Association of familial factors and environmental factors with cognitive late effects.
Linear mixed-effects models will be used to examine changes from baseline over time in cognitive outcomes (as described above) with familiar and environmental factors (as described above).
Time frame: Baseline through 5 years after enrollment
Evaluate family interest in caregiver education combined with interactive neurodevelopmental games.
The neurocognitive intervention consists of the Working for Kids (WFK) education, which is designed to improve parent understanding of the importance of the early learning environment on brain development, and First Pathways Game (FPG), which are interactive neurodevelopmental games designed for parents to play with their children to strengthen brain pathways for specific skills including communication, problem-solving and social emotional skills, motor skills, math skills and early science learning. Family interest in this intervention will be measured by the proportion of families approached enrolling on study.
Time frame: Baseline through 6 months after enrollment
Evaluate intervention feasibility by measuring the rate of participants completing a caregiver education combined with interactive. neurodevelopmental games.
The neurocognitive intervention consists of the Working for Kids (WFK) education, which is designed to improve parent understanding of the importance of the early learning environment on brain development, and First Pathways Game (FPG), which is an interactive neurodevelopmental games designed for parents to play with their children to strengthen brain pathways for specific skills including communication, problem-solving and social emotional skills, motor skills, math skills and early science learning. Intervention feasibility will be measured by the proportion of randomized participants completing at least 10 neurodevelopmental games.
Time frame: Baseline through 6 months after enrollment
Evaluate the acceptability of a caregiver education combined with interactive neurodevelopmental games.
The neurocognitive intervention consists of the Working for Kids (WFK) education, which is designed to improve parent understanding of the importance of the early learning environment on brain development, and First Pathways Game (FPG), which is an interactive neurodevelopmental games designed for parents to play with their children to strengthen brain pathways for specific skills including communication, problem-solving and social emotional skills, motor skills, math skills and early science learning. Acceptability will be measured as the proportion of caregivers reporting benefit from the intervention participation on a satisfaction questionnaire.
Time frame: Baseline through 6 months after enrollment
Magnitude of change in cognition and social-emotional development associated with a caregiver education program combined with interactive neurodevelopmental games.
Mean six-month change from baseline in cognition and social-emotional development as measured by DAYC-2 (parent interview) will be computed for families randomized to the intervention (described above) and for families randomized to the standard care control group.
Time frame: Baseline and 6 months after enrollment
To characterize the plasma systemic clearance (CL) of cyclophosphamide (CTX) in infants and young children with medulloblastoma.
Drug plasma concentrations will be simultaneously analyzed with a population pharmacokinetic approach, which permits characterizing typical pharmacokinetics and interindividual variability within the population. We will use a similar approach to what we have used in our previously published manuscripts. Cyclophosphamide CL will be estimated based on serial samples acquired during therapy.
Time frame: Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To characterize the area under the concentration-time curve (AUC0-24h) of carboxyethylphosphoramide (CEPM) in infants and young children with medulloblastoma receiving cyclophosphamide.
Carboxyethylphosphoramide will be included in above described population pharmacokinetic approach. Based on the results of the population pharmacokinetic analysis, the CEPM AUC0-24h can be calculated.
Time frame: Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To characterize the area under the concentration-time curve (AUC0-24h) of 4-hydroxy-cyclophosphamide (4OHCTX) in infants and young children with medulloblastoma receiving cyclophosphamide.
In a similar manner to the CEPM AUC0-24h, the 4-hydroxy-cyclophosphamide area under the curve AUC0-24h can be estimated based on the results of the population pharmacokinetic analysis.
Time frame: Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in in the plasma systemic clearance (CL) of CTX in infants and young children with medulloblastoma receiving CTX.
A covariate analysis will be performed to investigate potential associations between the CTX CL pharmacokinetic parameter (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in CTX CL values in infants and young children with medulloblastoma receiving CTX.
Time frame: Data for CTX from Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in CEPM AUC0-24h in infants and young children with medulloblastoma receiving CTX.
A covariate analysis will be performed to investigate potential associations between the CTX AUC pharmacokinetic parameter (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in CEPM AUC values in infants and young children with medulloblastoma receiving CTX.
Time frame: Data for CEPM from Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in 4OHCTX AUC0-24h in infants and young children with medulloblastoma receiving CTX.
A covariate analysis will be performed to investigate potential associations between the 4OHCTX AUC pharmacokinetic parameter (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in 4OHCTX AUC values in infants and young children with medulloblastoma receiving CTX.
Time frame: Data for 4OHCTX from Day 9 of the first course of A, AIVT, B or BIVT therapy and Days 4 and 5 of course C or Days 2 and 3 of E.
To characterize the plasma systemic clearance (CL) of vincristine (VCR) in infants and young children with medulloblastoma.
As with cyclophosphamide, the vincristine drug plasma concentrations will be analyzed with a population pharmacokinetic approach, which permits characterizing typical pharmacokinetics and interindividual variability within the population. Vincristine CL will be estimated based on serial samples acquired during therapy.
Time frame: Beginning on Day 15 of the first course of A or AIVT and B or BIVT (or Day 8 of one course E).
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in VCR PK parameter (CL) in infants and young children with medulloblastoma receiving VCR.
A covariate analysis will be performed to investigate potential associations between the VCR CL pharmacokinetic parameter (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in VCR CL values in infants and young children with medulloblastoma receiving VCR.
Time frame: Beginning on Day 15 of the first course of A or AIVT and B or BIVT (or Day 8 of one course E).
To characterize the plasma systemic clearance (CL) of topotecan (TPT) in infants and young children with medulloblastoma.
The topotecan drug plasma concentrations will be analyzed with a population pharmacokinetic approach, which permits characterizing typical pharmacokinetics and interindividual variability within the population. Topotecan CL will be estimated based on serial samples acquired during course C of therapy.
Time frame: All samples acquired during each course C for domestic patients and patients at St. Jude only.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in TPT PK parameter (CL) in infants and young children with medulloblastoma receiving TPT.
A covariate analysis will be performed to investigate potential associations between the TPT CL pharmacokinetic parameter (outcome measure) and demographics and clinical chemistry data (covariates). Also included in this analysis will be concomitant medications given at the same as topotecan (i.e., cyclophosphamide), as well as concomitant adjuvant drugs given within 48 hr of topotecan dose in at least 30% of patients included in the analysis. Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Patient age will be tested according to a Hill equation to reflect potential maturation process. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, and a covariate was considered significant at P\<0.05 for the forward addition and at the 0.01 for the backward addition.
Time frame: All samples acquired during each course C for domestic patients and patients at St. Jude, only.
To characterize the plasma systemic methotrexate (MTX) clearance (CL) in infants and young children with medulloblastoma.
Drug plasma concentrations will be simultaneously analyzed with a population pharmacokinetic approach, which permits characterizing typical pharmacokinetics and interindividual variability within the population. We will use a similar approach to what we have used in our previously published manuscripts. Methotrexate CL will be estimated based on serial samples acquired during the first day of each course of therapy.
Time frame: Day 1 of each course A, AIVT, B, and BIVT.
To characterize the area under the concentration-time curve (AUC0-24h) of 7-hydroxymethotrexate (7OHMTX) in infants and young children with medulloblastoma receiving methotrexate.
7-hydroxymethotrexate will be included in above described population pharmacokinetic approach. Based on the results of the population pharmacokinetic analysis, the 7OHMTX AUC0-24h will be calculated.
Time frame: Day 1 of each course A, AIVT, B, and BIVT.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in MTX PK parameter CL in infants and young children with medulloblastoma receiving MTX.
A covariate analysis will be performed to investigate potential associations between the MTX pharmacokinetic parameter CL (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in MTX CL values in infants and young children with medulloblastoma receiving MTX.
Time frame: Day 1 of each course A, AIVT, B, and BIVT.
To assess potential covariates (e.g., demographics, clinical chemistry) explaining inter- and intra-patient variability in 7OHMTX PK parameter AUC0-24h in infants and young children with medulloblastoma receiving MTX.
A covariate analysis will be performed to investigate potential associations between the MTX pharmacokinetic parameter AUC (outcome measure) and demographics and clinical chemistry data (covariates). Continuous covariates will be implemented according to a power model scaled to the population median covariate value. Categorical covariates will be modeled using an exponential change due to the covariate value. Significant covariates will be selected by using a classic forward/backward stepwise approach, with criteria P values of 0.05 and 0.01 for the forward and backward steps, respectively. Wald tests will be also used to test whether covariates should be kept in the model (criteria p-value\<0.05) to explain the inter- and intra-patient variability in 7OHMTX AUC values in infants and young children with medulloblastoma receiving MTX.
Time frame: Day 1 of each course A, AIVT, B, and BIVT.