Oral tetrahydrouridine plus decitabine for relapsed or refractory MDS

Phase 1 Study of Oral Tetrahydrouridine-Decitabine to Treat Relapsed or Refractory Myelodysplastic Syndromes

Phase 1 Interventional Treebough Therapies · NCT07006025

This trial tests a weekly oral combination of tetrahydrouridine and decitabine in adults with relapsed or refractory MDS to see if it is safe and reduces hospital days.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years and up
SexAll
SponsorTreebough Therapies Industry-sponsored
Locations1 site (The Bronx, New York)
Trial IDNCT07006025 on ClinicalTrials.gov

What this trial studies

This single-arm, open-label Phase 1 trial gives oral tetrahydrouridine (THU) with decitabine once weekly for up to 24 weeks to adults with relapsed or refractory myelodysplastic syndromes. The primary goal is to define safety and capture hematologic and nonhematologic toxicities. Secondary outcomes include response rates by International Working Group criteria, quality of life measures, number of days hospitalized, and measurement of DNMT1 protein levels in bone marrow and peripheral blood. Participants keep symptom diaries and attend clinic visits approximately every four weeks for testing and follow-up.

Who should consider this trial

Good fit: Adults (>=18) with relapsed or refractory MDS after at least one prior therapy, ECOG performance status <=3, adequate organ function, body weight >=41 kg, and ability to consent and comply with study procedures are ideal candidates.

Not a fit: Patients with acute promyelocytic leukemia, those previously treated with four or more 28-day cycles of decitabine, or those requiring contraindicated medications such as certain cytidine deaminase substrates or inhibitors are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, this oral combination could offer a more convenient treatment that lowers hospital time and maintains or improves disease control.

How similar studies have performed: Early-phase work using THU to enable oral decitabine delivery has shown promising pharmacologic activity and DNMT1 targeting but remains investigational.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients must have a diagnosis of MDS that has received one or more prior standard therapies and is relapsed or refractory
* Patients must be 18 years of age or older
* Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 3
* Patients must have adequate end-organ function
* Patient's body weight must be ≥ 41 kg
* Subjects must be able to understand and willing to sign a written informed consent document and complete study-related procedures.

Exclusion Criteria:

* Diagnosis of acute promyelocytic leukemia (APL)
* Prior treatment with ≥4 28-day cycles of parenteral or oral decitabine
* No other disease-directed therapy, save for hydroxyurea, including experimental or investigational drug therapy for 14 days prior to study entry (hydroxyurea should be discontinued ≥24 hours prior to initiation of study drug)
* Requiring concomitant treatment with drugs that are cytidine deaminase (CDA) substrates and/or inhibitors, e.g., cytarabine, 5-azacytidine, gemcitabine
* Currently pregnant or breastfeeding. Females of childbearing potential must have a negative serum pregnancy test within 72 hours of treatment start.
* Uncontrolled intercurrent illness that could limit life expectancy or ability to complete study correlates
* Women of Childbearing Potential (WOCBP) who are unwilling to agree to use dual contraceptive measures (i.e., hormonal or barrier method of birth control; abstinence, condom) prior to study entry, for the duration of study participation, and until 6 months after taking the last dose of THU/decitabine
* Sexually active male who is unwilling to use a condom when engaging in any sexual contact with a WOCBP, beginning at the screening visit and continuing until 6 months after taking the last dose of THU/decitabine
* 9\. Patients with uncontrolled active human retrovirus (HIV) infection, as this will further increase the risk for opportunistic infections. However, patients with HIV with undetectable viral load by polymerase chain reaction (PCR), without opportunistic infection, and on a stable regimen of antiretroviral therapy are eligible

Where this trial is running

The Bronx, New York

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions MDS
Last reviewed 2026-06-13 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.