NCT04640987 · Porteus, Matthew, MD
Stem Cell Transplant From Donors After Alpha Beta Cell Depletion in Children and Adults With T-allo10 Cells Addback
What this study is about
The purpose of this study is to determine the safety of a cell therapy, T-allo10, after αβdepleted-HSCT in the hopes that it will boost the adaptive immune reconstitution of the patient while sparing the risk of developing severe Graft-versus-Host Disease (GvHD).
View original scientific description
The purpose of this study is to determine the safety of a cell therapy, T-allo10, after αβdepleted-HSCT in the hopes that it will boost the adaptive immune reconstitution of the patient while sparing the risk of developing severe Graft-versus-Host Disease (GvHD). The primary objective of Phase 1a is to determine the recommended Phase 2 dose (RP2D) administered after infusion of αβdepleted-HSCT in children and young adults with hematologic malignancies. A Phase 1b extension will occur after dose escalation, enrolling at the RP2D for the T-allo10 cells determined in the Phase 1 portion to evaluate the safety and efficacy of infusion of T-allo10 after receipt of αβdepleted-HSCT. Additionally, Phase 1b aims to explore improvements in immune reconstitution.
Interventions
BIOLOGICAL
Allogeneic Stem Cell Transplant
The allogeneic stem cell transplant involves transferring the stem cells from a healthy person (donor) to the participant via infusion.
DEVICE
CliniMACS Prodigy System
Device used for production of T-allo10 cells.
DRUG
T-allo10 cells addback
T-allo10 cells are made by manipulating the participant's stem cell donor's white blood cells (CD4+ T cells) in the presence of their (participant's) CD14+ monocytes.
Primary outcome measures
Recommended Phase 2 Dose (RP2D) of T-allo10 in Phase 1a
Time frame: Up to 28 days after infusion of T-allo10 for each dosing cohort and Day +60 (+/- 10 days) after αβdepleted-HSCT
RP2D was determined by testing 3 different escalating doses (1x10\^5, 3x10\^5 and 1x10\^6 cells/Kg recipient body weight) in dose escalation cohorts 1 to 3 with 3 to 6 participants each. RP2D reflects the acceptable dose levels that did not cause a Dose-Limiting Toxicity (DLT) in ≥33% of participants and resulted in success with response in \>83% of participants. DLTs were defined as Grade IV aGvHD post T-allo10 infusion; any grade 3 or 4 related TEAE; any grade 3 or 4 suspected AE. Success with response was defined as achieving CD4+ IR by Day +60 (+/- 10 days) after αβdepleted-HSCT.
Number of participants with absence of dose-limiting toxicity (DLT)
Time frame: Assessed at 28 days (after infusion of T-allo10)
Grade IV aGvHD post T-allo10 infusion; any grade 3 or 4 related treatment emergent adverse events (TEAE); any grade 3 or 4 suspected AE
Number of participants who reach immune reconstitution (IR) threshold
Time frame: Up to Day 60 (+/- 10 days) after αβdepleted-HSCT
IR (a surrogate of reduced risk of leukemia recurrence) is defined reaching the threshold of 50CD3+CD4+T-cells/µl by Day+60 (+/-10days).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- prior to enrollment:
- 1\. Age \> 1 months (with minimum weight of 10 Kg) and \< 45 years.
- 2\. Patients deemed eligible for allogeneic HSCT under the originating study, NCT 04249830
- 3\. Patients with life-threatening hematological malignancies for which HSCT has been recommended:
- High-risk ALL in 1st CR, ALL in 2nd or subsequent CR;
- High-risk AML in 1st CR, AML in 2nd or subsequent CR;
- Myelodysplastic syndrome;
- JMML (Juvenile myelomonocytic leukemia);
- Non-Hodgkin lymphomas in 2nd or subsequent CR;
- Other hematologic malignancies eligible for stem cell transplantation per institutional standard.
- 4\. All subjects ≥ 18 years of age must be able to give informed consent, or adults lacking capacity to consent must have a LAR available to provide consent. For subjects \<18 years old their LAR (i.e. parent or guardian) must give informed consent. Pediatric subjects will be included in age appropriate discussion and verbal assent will be obtained for those \> 7 years of age, when appropriate. Inclusion criteria prior to T-allo10 infusion:
- Patient already received αβdepleted-HSCT and has myeloid engraftment.
- Absence of active grade II aGvHD requiring \>0.5 mg/Kg of steroids or any diagnosis of grade III/IVaGvHD.
Exclusion criteria
- prior to MNC collection for Tallo-10 manufacturing.:
- Not eligible to receive HSCT on NCT04249830
- Received another investigational agent within 30 days of enrollment.
- Pregnancy (positive serum or urine beta-HCG) within 7 days of MNC donation.
- Patient or donor is not willing or able to undergo an additional non-mobilized apheresis for collection of MNC prior to donation of cells for participation in NCT04249830.
Where
- Palo Alto, California
Collaborators
California Institute for Regenerative Medicine (CIRM)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jan 8, 2026 · Source of record for eligibility and locations