A Phase 2 interventional study of Inotuzumab ozogamicin and ALLR3 in ACUTE LYMPHOBLASTIC LEUKEMIA, sponsored by Pfizer. Recruiting at 65 sites in 15 countries. Open to participants aged 1 Year to 17 Years. Per ClinicalTrials.gov, last updated 2026-09-24.
Sponsored by Pfizer · Phase 2, Interventional, and Treatment
This prospective, randomized, multicenter, open-label Phase 2 study is designed to evaluate the superiority of InO monotherapy vs ALLR3 after 1 cycle of induction treatment in paediatric participants (between 1 and \<18 years) with High Risk (HR) or very high risk (VHR) first bone marrow relapse CD22-positive BCP ALL, and to evaluate the safety and tolerability, PK and long-term efficacy. Treatment with study intervention will end after induction therapy; follow-up will continue for up to 5 years from randomization.
This prospective, randomized, multicenter, open-label, Phase 2 study is designed to evaluate the superiority of InO monotherapy vs ALLR3, after 1 cycle of induction treatment in paediatric participants (between 1 and \<18 years) with HR or VHR first bone marrow relapse CD22-positive BCP ALL, and to evaluate the safety and tolerability, PK and long-term efficacy. Treatment with study intervention will end after induction therapy; follow-up for efficacy and safety will continue for up to 5 years from randomization.
End of Treatment is defined as occurring upon recovery from 1 cycle of study therapy (Day 28 ± 2 days), or one day before initiation of new anticancer therapy, whichever occurs first.
Approximately 100 participants will be randomized (2:1) to receive 1 cycle of either InO monotherapy or ALLR3 (block 1) therapy during induction. Two interim analyses (approximately 50% and 75% enrollment) fort the primary outcome measure followed by a final analysis are planned to assess efficacy and futility (non-binding).
After completion of induction therapy (ie, study therapy), it is anticipated that the majority of responding participants will proceed immediately to consolidation therapy. Non-responders are expected to proceed with salvage therapy at the investigator's discretion. Participants responding to induction therapy are expected to proceed to SOC consolidation therapy upon recovery of blood counts, but no sooner than 7 days after last dose of study intervention.
All participants (responders and non-responders) will proceed to long-term follow-up for this study. All subsequent anticancer therapy will be determined by the treating physician.
2,584 studies on the registry are indexed under Precursor Cell Lymphoblastic Leukemia-Lymphoma; 473 are open to participants now.
This study's planned enrollment of 100 is above the median of 40 across 1,952 interventional studies indexed under Precursor Cell Lymphoblastic Leukemia-Lymphoma.
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Of its 601 completed or terminated interventional studies of FDA-regulated products, 391 (65%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Morphologically confirmed diagnosis of first relapse HR or VHR BCP ALL; HR first relapse is defined as relapse occurring within 18 to 30 months of original diagnosis of ALL or within 6 months of completion of primary therapy, and lacking any identified very high-risk genetic abnormalities (Groeneveld-Krentz et al, 2019) (ie, KMT2A::AFF1 fusion [t(4;11)(q21;q23)], TCF3-HLF fusion [t(17;19)(q22;p13)], TCF3-PBX1 fusion [t(1;19)(q23;p13.3)], hypodiploidy [\<40 chromosomes] or masked low hypodiploidy (Molina et al, 2021), TP53 alteration). VHR first relapse is defined as relapse within 18 months of original diagnosis of ALL and/or with any of the following genetic abnormalities at original diagnosis or at relapse (Groeneveld-Krentz et al, 2019) (ie, KMT2A::AFF1 fusion [t(4;11)(q21;q23)], TCF3-HLF fusion [t(17;19)(q22;p13)], TCF3-PBX1 fusion [t(1;19)(q23;p13.3)], hypodiploidy [\<40 chromosomes] or masked low hypodiploidy (Molina et al, 2021), TP53 alteration).
Adequate serum chemistry parameters:
6 Participants with combined bone marrow and testicular relapse are eligible assuming orchiectomy is performed prior to randomization or is planned at the end of induction therapy.
5.2. Exclusion Criteria
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.
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.
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.
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.
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.
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.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
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.
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.
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.
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.
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.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
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.
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.
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.
Each participant in the InO arm will receive 1 course (3 doses) of InO, as follows: * Day 1: 0.8 mg/m2 * Days 8 (±1 day) and Day 15 (±1 day): 0.5 mg/m2/dose
Drug: Inotuzumab ozogamicin
Mitoxantrone 10 mg/m2 on Days 1 and 2 Vincristine 1.5 mg/m2 (max single dose 2 mg) administered on Days 3, 10, 17 and 24 Dexamethasone 20 mg/m2/day administered orally (or IV) divided into two daily doses (maximum 40 mg/day) as two 5-day blocks on Days 1-5 and Days 15-19. PEG-asparaginase 1000 units/m2 IV administered on Days 3 and 17. In case of hypersensitivity/allergic reaction to PEG-asparaginase, each dose of PEG-asparaginase will be replaced by Erwinia-asparaginase at a dose of 20,000 units/m² IV or IM every other day for a total of 6 doses
Drug: ALLR3
Inotuzumab ozogamicin (BESPONSA™) is a CD22 targeted antibody drug conjugate (ADC) approved in several countries for the treatment of adults with relapsed or refractory B cell precursor acute lymphoblastic leukemia (ALL). The approved starting dose is 1.8mg/m2/cycle.
Also known as: Besponsa
The ALLR3 chemotherapy regimen (vincristine, mitoxantrone, dexamethasone, and PEG-asparaginase \[or erwinia-asparaginase in the event of an allergic reaction to PEG-asparaginase\]) has been adopted by pediatric oncology groups as treatment for pediatric relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL)
Also known as: R3
Minimum Residual Disease (MRD) Negativity in participants achieving complete response (CR), complete response with incomplete platelet count recovery (CRp), or complete response with incomplete count recovery (CRi)
MRD negativity status is determined based on the minimum MRD percentage between the date of CR/CRp/CRi and end of treatment test as assessed by RQ-PCR, with reflex to FC result if MRD is non-evaluable by RQ-PCR
Time frame: After 1 treatment cycle: Day 28 +/- 2 days
Event Free Survival (EFS)
EFS will be summarized using Kaplan-Meier methods and displayed graphically by treatment arm.
Time frame: From study start to first event (progression, relapse, failure to achieve CR/CRp/CRi by the end of induction, MRD persistence prior to HSCT [hematopoietic stem cell transplant], second malignancy, or death): up to 5 years from randomization
Duration of Response (DoR) for Participants Who Achieved CR/CRp/CRi
DoR will be summarized using Kaplan-Meier methods.
Time frame: From date of first response to date of first event (objective progression, relapse as determined by investigator assessment, MRD persistence prior to HSCT, or death due to any cause, whichever occurs first): up to 5 years from End of Treatment
Rate of hematopoietic stem cell transplantation (HSCT)
HSCT rate will be summarized by descriptive analyses (ie, percentage of participants who underwent HSCT after treatment).
Time frame: Up to 5 years from randomization
Overall Survival (OS)
OS will be summarized by treatment arm using Kaplan-Meier methods.
Time frame: From start of treatment to date of death due to any cause: up to 5 years from randomization
Number of participants reporting an Adverse Event (AE)
The number and percentage of participants who experienced any AE, SAE (Serious Adverse Event), treatment related AE, and treatment related SAE will be summarized according to worst toxicity grades.
Time frame: From time of informed consent up to a minimum of 60 calendar days after the last dose of study drug.
Pharmacokinetics (PK) parameter: InO Cmax
Descriptive summary statistics will be provided for InO serum concentrations at scheduled visits.
Time frame: 1 treatment cycle: 28 days
Number of Adverse Events (AE) reported by severity
AEs will be graded by the investigator according to the CTCAE (Common Terminology Criteria for Adverse Events) version 4.03.
Time frame: From time of informed consent up to a minimum of 60 calendar days after the last dose of study drug.
Pharmacokinetics (PK) parameter: InO trough levels
Descriptive summary statistics will be provided for InO serum concentrations at scheduled visits.
Time frame: 1 treatment cycle: 28 days
Rate of Chimeric antigen receptor (CAR) T-cell therapy
CAR T-cell therapy rate will be summarized by descriptive analyses (ie, the number, percent of participants who underwent CAR T-cell therapy after treatment).
Time frame: Up to 5 years from randomisation
Plan to share: Yes — Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.
Data sharing details ↗ · www.pfizer.com
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