A Phase 2 interventional study of Irinotecan and Temozolomide in Recurrent Medulloblastoma and Recurrent Ependymoma, sponsored by Pediatric Brain Tumor Consortium. Active, not recruiting at 3 sites in United States. Open to participants aged Up to 21 Years. Per ClinicalTrials.gov, last updated 2026-07-28.
Sponsored by Pediatric Brain Tumor Consortium · Phase 2, Interventional, and Treatment
A Phase 2 study investigating the addition of cRIT 131I-omburtamab to irinotecan, temozolomide, and bevacizumab for patients with recurrent medulloblastoma. A feasibility cohort is included to assess the feasibility of incorporating cRIT 131I-omburtamab for patients with recurrent ependymoma.
Direct intraventricular delivery of radiolabeled tumor-specific antibodies may aid in both the detection and treatment of recurrent disease for these highly specific pediatric patients with recurrent tumors.
Stratum 1: This is a phase 2 single-arm open-label study that will define event-free survival (EFS) and overall survival (OS) following therapy with irinotecan, temozolomide, bevacizumab, and compartmental (intraOmmaya) radioimmunotherapy (cRIT) 131I-omburtamab in patients with recurrent medulloblastoma. Patients with recurrent medulloblastoma will undergo surgery if feasible prior to study entry, followed by Induction Chemotherapy with irinotecan, temozolomide, and bevacizumab on study as per the Children's Oncology Group (COG) trial ACNS0821. Following 2 or 4 courses of chemotherapy and if radiographic disease status is stable or improved, patients may continue to Radioimmunotherapy to receive 2 therapeutic doses (50 mCi each) of cRIT 131I-omburtamab. Following Radioimmunotherapy, patients may resume to Maintenance Chemotherapy with irinotecan, temozolomide, and bevacizumab for up to 12 total courses of chemotherapy or until disease progression, whichever occurs sooner. The primary comparison for this study will be the medulloblastoma cohort treated on ACNS0821 on the irinotecan + temozolomide + bevacizumab arm (N=52).
Stratum 2: This is a feasibility cohort. The primary objective is to assess feasibility of incorporating cRIT 131I-omburtamab for patients with recurrent ependymoma and to assess dosimetry. Patients must have progressed after initial surgery, radiation therapy, or other therapies. Patients will undergo surgery (if feasible) prior to study entry with the goal of achieving stable or better disease. Tumors (archived or new) will be tested for B7H3 prior to enrollment. If positive, patients will enroll on Stratum 2 and receive one dosimetry dose (2 mCi) of cRIT 131I-omburtamab with nuclear medicine scintigraphy (typically using 3 whole-body planar gamma camera imaging and at least 1 head SPECT scan or SPECT/CT) using SPECT during the Dosimetry Course (14 days in length). Following the Dosimetry Course and within 2 weeks of the dosimetry dose, patients may continue to Radioimmunotherapy to receive 2 therapeutic doses (50 mCi each) of cRIT 131I-omburtamab.
317 studies on the registry are indexed under Medulloblastoma; 51 are open to participants now.
This study's planned enrollment of 62 is above the median of 31 across 255 interventional studies indexed under Medulloblastoma.
Browse Medulloblastoma studies →Pediatric Brain Tumor Consortium is the lead sponsor of 31 studies on the registry; none are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 5 (100%) have results posted.
Counted across the registry records on this site, refreshed daily.
INCLUSION CRITERIA: Stratum 1
Radiation - Patients must have had their last fraction of:
Organ Function - Patients must have:
EXCLUSION CRITERIA: Stratum 1
Patients currently receiving any of the following medications and cannot be discontinued 7 days prior to enrollment are ineligible:
INCLUSION CRITERIA FOR SCREENING: Stratum 2
INCLUSION CRITERIA FOR ENROLLMENT: Stratum 2
Patients must have had their last fraction of:
Organ Function
EXCLUSION CRITERIA FOR ENROLLMENT: Stratum 2
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
This arm aims to estimate event-free survival (EFS) and overall survival (OS) following therapy with irinotecan, temozolomide, bevacizumab, and compartmental (intraOmmaya) radioimmunotherapy (cRIT) 131I-omburtamab in patients with recurrent medulloblastoma. Patients with recurrent medulloblastoma will undergo surgery if feasible prior to study entry, followed by Induction Chemotherapy with irinotecan, temozolomide, and bevacizumab on study as per the Children's Oncology Group (COG) trial ACNS0821. Following 2 or 4 courses of chemotherapy and if radiographic disease status is stable or improved, patients will receive 2 therapeutic doses of 50 mCi cRIT 131I-omburtamab during Radioimmunotherapy. Following Radioimmunotherapy, patients may resume to Maintenance Chemotherapy with irinotecan, temozolomide, and bevacizumab for up to 12 total courses of chemotherapy or until disease progression, whichever occurs sooner.
Drug: Irinotecan · Drug: Temozolomide · Drug: Bevacizumab · Drug: Omburtamab I-131 · Drug: Liothyronine · Drug: SSKI · Drug: Dexamethasone · Drug: Antipyretic · Drug: Antihistamine · Drug: anti-emetics
This is a feasibility cohort. The primary objective is to assess feasibility of incorporating cRIT 131I-omburtamab for patients with recurrent ependymoma and to assess dosimetry. Patients must have progressed after initial surgery, radiation therapy, or other therapies. Patients will undergo surgery (if feasible) prior to study entry with the goal of achieving stable or better disease. Tumor tissue (archived or new) will be tested for B7H3 prior to enrollment. If positive, patients will enroll on Stratum 2 and receive one dosimetry dose (2 mCi) of cRIT 131I-omburtamab with nuclear medicine scintigraphy using SPECT during the Dosimetry Course (14 days in length). Following the Dosimetry Course and within 2 weeks of the dosimetry dose, patients may continue to Radioimmunotherapy to receive 2 therapeutic doses (50 mCi) of cRIT 131I-omburtamab.
Drug: Omburtamab I-131 · Drug: Liothyronine · Drug: SSKI · Drug: Dexamethasone · Drug: Antipyretic · Drug: Antihistamine · Drug: anti-emetics
Irinotecan is a semisynthetic water-soluble analog of camptothecin (a plant alkaloid isolated from Camptotheca acuminata). Irinotecan is available in single-dose amber glass vials in 40 mg (2 mL) and 100 mg (5 mL), 300 mg (15 mL), and 500 mg (25 mL). Patients on Stratum 1 will be given irinotecan at 50 mg/m2/day IV on Days 1 through 5 of each chemotherapy course.
Also known as: CPT-11,
An orally administered alkylating agent, a second generation imidazotetrazine. A prodrug of MTIC, temozolomide spontaneously decomposes to MTIC at physiologic pH. Exerts its effect by cross-linking DNA. Temozolomide capsules are available in six different strengths (5, 20, 100, 140, 180, 250 mg). The capsules vary in size, color, and imprint according to strength. In the US, capsules are packaged in 5-count and 14-count bottles. Patients on Stratum 1 will be given temozolomide at 150 mg/m2/dose PO on Days 1-5 of each chemotherapy course.
Bevacizumab is a recombinant humanized anti-vascular endothelial growth factor (anti-VEGF) monoclonal antibody. Bevacizumab is supplied as a clear to slightly opalescent, sterile liquid ready for parenteral administration. Each 400 mg (25 mg/mL, 16 mL fill) glass vial contains bevacizumab with phosphate, trehalose, polysorbate 20, and Sterile Water for Injection. Patients on Stratum 1 will be given bevacizumab at 10 mg/kg/day IV on Days 1 and 15 of each chemotherapy course, with the exception of the last course of Induction Chemotherapy (i.e., Course 2 or 4) where it will be administered on Day 1 only.
Also known as: rhuMAb VEGF, Avastin®)
Omburtamab is a murine IgG1 monoclonal antibody (mAb) against B7-H3 (CD276) manufactured by in vivo growth of the hybridoma cell line without the use of animal-derived components. Omburtamab will be radiolabeled with iodine-131 at a designated radiolabeling facility. 131I-omburtamab is supplied as a sterile, injectable, radioactive product in a vial. Each supplied vial will contain enough radioactivity to prepare 50 mCi of 131I-omburtamab, formulated in 3.5-4 mL of solution. 131I-omburtamab should be administered via an intraventricular access device (i.e., Ommaya catheter or programmable VP shunt). Radioimmunotherapy consists of 56 days. Patients on Stratum 1 will receive a therapeutic dose of 50 mCi cRIT 131I-omburtamab on Days 8 and 36 of Radioimmunotherapy. Patients on Stratum 2 will receive a therapeutic dose of 50 mCi cRIT 131I-omburtamab on Days 1 and 29 of Radioimmunotherapy.
Liothyronine (or equivalent) will be given as premedication for 131I-omburtamab to prevent thyroid accumulation. Liothyronine (or equivalent) will be administered at 25 µg PO, NG, or G-tube (if weight \< 25 kg) or 50 µg PO, NG, or G-tube (if weight ≥ 25 kg) daily starting on Day 1 of Radioimmunotherapy (for Stratum 1 patients) or Day 1 of Dosimetry (for Stratum 2 patients), with a mandated minimum of 7 days before each 131I-omburtamab injection and 14 days after each 131I-omburtamab injection. On the day of the 131I-omburtamab injection, administer any time before the injection.
SSKI (potassium iodide) will be given as premedication for 131I-omburtamab to prevent thyroid accumulation. SSKI (potassium iodide) will be administered as 7 drops (\~0.35 mL) PO, NG, or G-tube daily starting on Day 1 of Radioimmunotherapy (for Stratum 1 patients) or Day 1 of Dosimetry (for Stratum 2 patients), with a mandated minimum of 7 days before each 131I-omburtamab injection and 14 days after each 131I-omburtamab injection. On the day of the 131I-omburtamab injection, administer any time before the injection.
Also known as: Potassium iodide
Dexamethasone will be given as premedication for 131I-omburtamab to prevent possible meningeal inflammatory reaction. Starting within 24 hours prior to each 131I-omburtamab injection, dexamethasone will be administered orally at 0.5 mg (if weight \< 15 kg) or 1 mg (if weight ≥ 15 kg) twice-daily doses for a total of 6 doses to alleviate infusion-related AEs: Two doses starting 24 hours pre-131I-omburtamab injection, two doses on the day of the injection (can be given before or after), and two doses 24 hours post-131I-omburtamab injection.
An antipyretic (e.g., oral acetaminophen \[15 mg/kg, 650 mg maximum\] or equivalent) will be given as premedication for 131I-omburtamab within 1 to 3 hours before each 131I-omburtamab injection.
An antihistamine (e.g., IV diphenhydramine \[1 mg/kg, 50 mg maximum\] or equivalent) will be given as premedication for 131I-omburtamab within 1 to 3 hours before each 131I-omburtamab injection.
An anti-emetic (e.g., IV ondansetron \[0.25 mg/kg, 16 mg maximum\] or equivalent) will be given as premedication for 131I-omburtamab within 1 to 3 hours before each 131I-omburtamab injection.
2-year event free survival (EFS) in the Recurrent Medulloblastoma Cohort
Using the Kaplan Meier method, estimate of event-free survival (EFS) of patients with relapsed medulloblastoma treated with the study regimen. EFS is defined as the interval of time between enrollment on the study and the minimum date of documentation of progressive disease, death due to any cause, subsequent malignancy or date of last follow-up.
Time frame: 2 years
Percentage of Patients who met feasibility criteria in the Recurrent Ependymoma Cohort
Percentage of patients who met feasibility criteria of incorporating cRIT 131I-omburtamab treatment for patients with recurrent ependymoma. Patients who meet both of the following criteria will be counted as feasibility successes: 1) Administration of the first therapeutic dose of the antibody at the treating institution within 6 days of labeling. 2) Successful acquisition of all 3 SPECT scans during the Dosimetry Course prior to Radioimmunotherapy.
Time frame: 3 months
Overall survival (OS) in in Recurrent Medulloblastoma Cohort
Using the Kaplan Meier method, estimate of the overall survival (OS) of patients with recurrent medulloblastoma treated with the study regimen. OS is defined as the interval of time between enrollment on the study and the minimum date of death due to any cause or date of last follow-up.
Time frame: 5 years
Percentage of Recurrent Ependymoma patients with B7H3 reactivity
All recurrent ependymoma patients must be screened for B7H3 reactivity to be eligible for treatment on this study. B7H3 reactivity in pre-treatment formalin-fixed and paraffin-embedded tumor tissue will be assessed by IHC performed in a CLIA-certified lab. Patients whose tumors meet the reactivity criteria will be counted towards this percentage over the total number of patients who were screened.
Time frame: 1 month
Event free survival (EFS) for Recurrent Ependymoma
Using the Kaplan Meier method, estimate of EFS of patients with recurrent ependymoma following incorporation of intraOmmaya 131I-omburtamab treatment. EFS is defined as the interval of time between enrollment on the study and the minimum date of documentation of progressive disease, death due to any cause, subsequent malignancy or date of last follow-up.
Time frame: 5 years from enrollment completion
Overall survival (OS) for Recurrent Ependymoma
Using the Kaplan Meier method, estimate OS of patients with recurrent ependymoma following incorporation of intraOmmaya 131I-omburtamab treatment. OS is defined as the interval of time between enrollment on the study and the minimum date of death due to any cause or date of last follow-up.
Time frame: 5 years from enrollment completion
Estimate of Mean Absorbed Radiation Dose
To assess the distribution of 131I-omburtamab, Recurrent Ependymoma patients will receive one dosimetry dose (2 mCi) of cRIT 131I-omburtamab with three serial nuclear medicine scintigraphy using SPECT during the Dosimetry Course (1 week in length) prior to receiving the therapeutic dose. Organ dosimetry will be analyzed for whole body and regions of interest (ROI) and calculated based on nuclear imaging scans by whole-body planar gamma camera scans. ROIs in each planar dataset will be defined at each time point if signal is visibly above the immediate background. The mean absorbed radiation dose in CSF and whole blood will be estimated via imaging-based estimation (CSF).
Time frame: 1 month
Number of Recurrent Medulloblastoma and Ependymoma Participants with Grade 3 or higher 131I-omburtamab - Related Adverse Events as Assessed by CTCAE v5.0
Number of patients in the combined cohort (Recurrent Medulloblastoma and Ependymoma) who received at least 1 dose of 131I-omburtamab and experienced Adverse Events that were deemed at least possibly related to 131I-omburtamab will be reported by AE category as Assessed by CTCAE v5.0.
Time frame: 1 year
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
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Studies of the drugs tested here: Irinotecan · Temozolomide · Bevacizumab
Pediatric Brain Tumor Consortium