Clinical trial Recruiting at 6 sites Phase 2 Interventional Ages 18 and up

Orca-T after reduced-intensity or nonmyeloablative conditioning for adults with AML or MDS

Official title: A Phase 2 Trial of Orca-T Following Reduced Intensity or Nonmyeloablative Conditioning in Patients With Acute Myeloid Leukemia or Myelodysplastic Syndrome

Run by Orca Biosystems, Inc. · NCT07216443 · Data updated 2026-11-12

This trial will test whether Orca-T, a donor-derived stem cell and T-cell therapy, is safe and helps adults with acute myeloid leukemia or myelodysplastic syndrome who are receiving reduced-intensity or nonmyeloablative allogeneic stem cell transplants.

Quick facts

PhasePhase 2
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment80 (estimated)
SponsorOrca Biosystems, Inc.
Industry-sponsored
Drugs / interventionscyclophosphamide, fludarabine, immunotherapy
Locations6 sites (Los Angeles, California and 5 other locations)
StatusRecruiting
StartedDecember 9, 2025
Main results expectedNovember 2027
Study endsDecember 2028
Registry record updatedJuly 7, 2026
Trial IDNCT07216443 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults (≥18 years) with AML in complete remission (CR/CRi) or MDS appropriate for alloHCT who are planned for RIC or NMA conditioning and have an identified 8/8 HLA-matched related or unrelated donor are ideal candidates.

Probably not a fit

Patients who need myeloablative conditioning, lack an 8/8 HLA-matched donor, have active uncontrolled disease or significant organ dysfunction are unlikely to benefit from this protocol.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a multicenter, open-label phase 2 trial of Orca-T given to adults with acute myeloid leukemia (AML) in remission or to patients with myelodysplastic syndrome (MDS) who are eligible for reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) allogeneic hematopoietic cell transplantation (alloHCT). Orca-T is a donor-manufactured product composed of purified hematopoietic stem and progenitor cells (HSPCs), regulatory T cells (Tregs), and conventional T cells (Tcons) derived from an 8/8 HLA-matched related or unrelated donor. Participants receive the investigator-chosen RIC or NMA preparative regimen, Orca-T infusion from the matched donor, and single-agent graft-versus-host disease prophylaxis with tacrolimus. The trial further characterizes safety and tolerability and provides an initial look at efficacy in this lower-intensity transplant population, building on earlier phase 1 and ongoing phase 1b/3 experiences.

Why it matters

Potential benefit: If successful, Orca-T could lower graft-versus-host disease while preserving graft function and anti-leukemia activity, potentially improving survival and quality of life after lower-intensity transplants.

How similar studies have gone: Early-phase work, including a phase 1 study and ongoing phase 1b/3 trials of Orca-T in different conditioning settings, produced encouraging safety and preliminary efficacy signals that prompted this phase 2 evaluation.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Age ≥18 years at the time of enrollment
2. Diagnosed with 1 of the following diseases:

   1. Acute myeloid, or mixed phenotype leukemia in complete remission (CR) or CR with incomplete hematologic recovery (CRi), with or without the presence of known minimal residual disease.
   2. Myelodysplastic syndrome that is indicated for alloHCT per the 2017 International Expert Panel recommendations and/or therapy-related/secondary MDS as defined by the World Health Organization (WHO) classification of myeloid malignancies, with ≤10% blast burden in the bone marrow.
3. Planned to undergo 1 of the following preparative regimens as per Investigator discretion:

   1. RIC cohort: Planned RIC-alloHCT including RIC regimen with TBI/thiotepa/fludarabine
   2. NMA cohort: Planned NMA-alloHCT including NMA regimen with fludarabine/cyclophosphamide/TBI
4. Identified related or unrelated donor who is an 8/8 match for HLA-A, -B, -C, and -DRB1
5. Estimated glomerular filtration rate ≥30 mL/minute
6. Cardiac ejection fraction at rest ≥40% or shortening fraction of ≥22% by echocardiogram or radionuclide scan (MUGA)
7. Diffusing capacity of the lung for carbon monoxide (adjusted for hemoglobin) ≥40%
8. Negative serum or urine β-HCG test in persons of childbearing potential
9. Alanine transaminase (ALT)/aspartate transaminase (AST) \<5 times the upper limit of normal (ULN)
10. Total bilirubin \<3 × ULN
11. Deemed ineligible for a fully myeloablative alloHCT per assessment of the principal investigator

Exclusion Criteria:

1. Prior alloHCT
2. Currently receiving corticosteroids or other immunosuppressive therapy. Topical corticosteroids or oral systemic corticosteroid doses less than or equal to 10 mg/day are allowed.
3. Planned donor lymphocyte infusion (DLI)
4. Planned pharmaceutical in vivo or ex vivo T-cell depletion
5. Recipient-positive antidonor HLA antibodies against a mismatched allele in the selected donor
6. Karnofsky performance score \<60%
7. For RIC cohort only: HCT-Specific Comorbidity Index (HCT-CI) ≥6
8. Uncontrolled bacterial, viral, or fungal infection (currently taking antimicrobial therapy and with progression or no clinical improvement) at the time of enrollment
9. Seropositive for HIV-1 or -2, HTLV-1 or -2, hepatitis B surface antigen, or HCV antibody unless previously treated with curative therapy and are HCV NAT negative
10. Known allergy or hypersensitivity to or intolerance of tacrolimus
11. Documented allergy or hypersensitivity to iron dextran or bovine, murine, algal, or Streptomyces avidinii proteins
12. Any uncontrolled autoimmune disease requiring active immunosuppressive treatment
13. Concurrent malignancy within 1 year except nonmelanoma skin cancer that has been curatively resected
14. Psychosocial circumstances that preclude the participant being able to go through transplantation or participate responsibly in follow-up care
15. Persons who are pregnant or breastfeeding
16. Person of childbearing potential (POCBP) or men who have sexual contact with POCBP who are unwilling to use effective forms of birth control or abstinence for 1 year after transplantation.
17. Any serious medical condition or abnormality in clinical laboratory tests that, in the investigator's or medical monitor's judgment, precludes the recipient's safe participation in and completion of the trial or which could affect compliance with the protocol or interpretation of results

Where it's running

  • UCLA Department of Medicine
    Los Angeles, California, United States
    Recruiting
  • Moffitt Cancer Center
    Tampa, Florida, United States
    Recruiting
  • John Theurer Cancer Center at Hackensack University Medical Center
    Hackensack, New Jersey, United States
    Recruiting
  • Weill Cornell Medicine - New York Presbyterian Hospital
    New York, New York, United States
    Recruiting
  • Oregon Health and Science University
    Portland, Oregon, United States
    Recruiting
  • Vanderbilt University, Ingram Cancer Center
    Nashville, Tennessee, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.