HSCTPhase 2NCT07316595
Study of Treosulfan-Based Conditioning for HSCT in Nijmegen Breakage Syndrome
A Phase 2 study testing Treosulfan (Treo) in people with HSCT and Nijmegen Breakage Syndrome, run by Federal Research Institute of Pediatric Hematology, Oncology and Immunology.
Trial summary
Nijmegen breakage syndrome is one of the DNA repair defect disorders. A characteristic feature of these syndromes is a predisposition to the development of malignant neoplasms. The only curative option for the combined immunodeficiency in Nijmegen breakage syndrome is allogeneic hematopoietic stem cell transplantation… Read more about this study
- Who is it for?
- Ages Up to 21 years
- Conditions the study is for
- HSCT, Nijmegen Breakage Syndrome, Treosulfan Based Conditioning
- What is being tested?
- Treosulfan (Treo)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- No sites listed yet
- Study dates
- 30 Dec 2025to 31 Dec 2030
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Up to 21 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- genetically confirmed Nijmegen breakage syndrome
- availability of informed consent for study participation, signed by the patient (ages 14 to 21) and/or their legal representative (ages 0 to 18).
- absence of contraindications to HSCT based on the patient's somatic status.
Who cannot join
- other DNA repair deficiency syndromes (both specified and unspecified)
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: A Clinical Study of the Efficacy and Safety of Conditioning With Low Doses of Treosulfan Before Allogeneic Hematopoietic Stem Cell Transplantation for Patients With Nijmegen Breakage Syndrome
Nijmegen breakage syndrome is one of the DNA repair defect disorders. A characteristic feature of these syndromes is a predisposition to the development of malignant neoplasms. The only curative option for the combined immunodeficiency in Nijmegen breakage syndrome is allogeneic hematopoietic stem cell transplantation (HSCT). In addition to correcting the immunodeficiency, HSCT can reduce the risk of developing hematopoietic tumors.
Due to the increased sensitivity of cells in patients with Nijmegen breakage syndrome to alkylating drugs, the use of standard myeloablative conditioning regimens for this disease significantly increases the risks of toxic complications and transplant-related mortality.
Read more
Treosulfan is an alkylating agent that has demonstrated efficacy with comparatively low risks of toxic complications when used as part of conditioning prior to allogeneic HSCT for various diseases in patients of all age groups. There is currently experience using treosulfan in patients with Nijmegen breakage syndrome at reduced doses (21 and 30 g/m²). However, a number of questions remain unresolved. Based on our previous experience, a dose of 21 g/m² is sufficient for patients with Nijmegen breakage syndrome without a malignant disease, as it ensures good graft function (a high probability of full donor chimerism and control of the immunodeficiency). At the same time, there is reason to believe that this dose is insufficient to provide an antitumor effect from the conditioning.
We are planning a multicenter study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m².
- Being tested
- Treosulfan (Treo)
- Medical subject headings
- Nijmegen Breakage Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Treosulfan (Treo)Drug
We are planning a multicenter study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m²
| Study group | Role | What they receive |
|---|---|---|
| Patients with Nijmegen breakage syndrome without malignant disease. | Active comparator | Not described Receives: Drug: Treosulfan (Treo) |
| Patients with Nijmegen breakage syndrome and malignant disease. | Active comparator | Not described Receives: Drug: Treosulfan (Treo) |
What is being measured
The primary outcome is the main question the study is designed to answer.
To evaluate event-free survival (EFS), defined by the occurrence of death, graft rejection, or development of secondary malignancy/relapse.
Event-free survival in patients with Nijmegen syndrome is the primary criterion for assessing the effectiveness of HSCT. It was precisely the need to solve the problems of graft rejection, relapses of malignant diseases, and secondary tumors that became the main reasons for initiating this study.
Measured: 2 years
Secondary outcomes (8)
Overall survival
Measured: 2 years
To evaluate the rate of transplant-associated mortality.
Measured: 2 years
Number of Participants With Treatment-Related Adverse Events as Assessed by CTCAE v4.0
Measured: 3 months
Probability of graft rejection
Measured: 2 years
Frequency of Complete Donor and Mixed Chimerism after HSCT
Measured: 1 year
Incidence of acute GVHD.
Measured: 1 year
Incidence of chronic GVHD.
Measured: 2 years
To assess the kinetics of immune reconstitution
Measured: 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Jan 2026
- Study start30 Dec 2025 (estimated)
- Primary completion31 Dec 2028 (estimated)
- Study completion31 Dec 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HSCTStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- We are planning a study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m².
- Masking
- None (open label)
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Federal Research Institute of Pediatric Hematology, Oncology and Immunology
- Sponsor type
- University, hospital or other
- Collaborators
- Russian Children's Clinical Hospital of the N.I. Pirogov Russian National Research Medical University, Regional Children's Clinical Hospital, Yekaterinburg, Morozov Children's Municipal Clinical Hospital of the Moscow City Health Department State-Financed H, Raisa Gorbacheva Memorial Research Institute for Pediatric Oncology, Hematology and Transplantation
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07316595
- Sponsor's protocol ID
- NCHPOI- 2025-9
- Status last verified
- Dec 2025
- First submitted
- 20 Nov 2025
- Last updated
- 5 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Clinical Study of the Efficacy and Safety of Conditioning With Low Doses of Treosulfan Before Allogeneic Hematopoietic Stem Cell Transplantation for Patients With Nijmegen Breakage Syndrome
- ClinicalTrials.gov ID
- NCT07316595
- Acronym / sponsor ID
- NCHPOI- 2025-9
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- Federal Research Institute of Pediatric Hematology, Oncology and ImmunologyUniversity, hospital or other
- Collaborators
- Russian Children's Clinical Hospital of the N.I. Pirogov Russian National Research Medical University, Regional Children's Clinical Hospital, Yekaterinburg, Morozov Children's Municipal Clinical Hospital of the Moscow City Health Department State-Financed H, Raisa Gorbacheva Memorial Research Institute for Pediatric Oncology, Hematology and Transplantation
- Study start
- 30 Dec 2025 (estimated)
- Primary completion
- 31 Dec 2028 (estimated)
- Study completion
- 31 Dec 2030 (estimated)
- First posted
- 5 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Nijmegen breakage syndrome is one of the DNA repair defect disorders. A characteristic feature of these syndromes is a predisposition to the development of malignant neoplasms. The only curative option for the combined immunodeficiency in Nijmegen breakage syndrome is allogeneic hematopoietic stem cell transplantation (HSCT). In addition to correcting the immunodeficiency, HSCT can reduce the risk of developing hematopoietic tumors.
Due to the increased sensitivity of cells in patients with Nijmegen breakage syndrome to alkylating drugs, the use of standard myeloablative conditioning regimens for this disease significantly increases the risks of toxic complications and transplant-related mortality.
Treosulfan is an alkylating agent that has demonstrated efficacy with comparatively low risks of toxic complications when used as part of conditioning prior to allogeneic HSCT for various diseases in patients of all age groups. There is currently experience using treosulfan in patients with Nijmegen breakage syndrome at reduced doses (21 and 30 g/m²). However, a number of questions remain unresolved. Based on our previous experience, a dose of 21 g/m² is sufficient for patients with Nijmegen breakage syndrome without a malignant disease, as it ensures good graft function (a high probability of full donor chimerism and control of the immunodeficiency). At the same time, there is reason to believe that this dose is insufficient to provide an antitumor effect from the conditioning.
We are planning a multicenter study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m².
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- We are planning a study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m².
| Arm | Type | Receives |
|---|---|---|
| Patients with Nijmegen breakage syndrome without malignant disease. | Active comparator | Drug: Treosulfan (Treo) |
| Patients with Nijmegen breakage syndrome and malignant disease. | Active comparator | Drug: Treosulfan (Treo) |
Who may qualify
- Ages
- Up to 21 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (3 listed)
- genetically confirmed Nijmegen breakage syndrome
- availability of informed consent for study participation, signed by the patient (ages 14 to 21) and/or their legal representative (ages 0 to 18).
- absence of contraindications to HSCT based on the patient's somatic status.
Key exclusion criteria (1 listed)
- other DNA repair deficiency syndromes (both specified and unspecified)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Treosulfan (Treo)We are planning a multicenter study to investigate treosulfan-based conditioning in patients with Nijmegen breakage syndrome, which will stratify patients based on the presence or absence of malignant disease. Patients without a tumor will receive treosulfan at a dose of 21 g/m², and patients with a tumor will receive 30 g/m² | Drug | Patients with Nijmegen breakage syndrome and malignant disease., Patients with Nijmegen breakage syndrome without malignant disease. |
Primary outcome
To evaluate event-free survival (EFS), defined by the occurrence of death, graft rejection, or development of secondary malignancy/relapse.
Time frame: 2 years
Event-free survival in patients with Nijmegen syndrome is the primary criterion for assessing the effectiveness of HSCT. It was precisely the need to solve the problems of graft rejection, relapses of malignant diseases, and secondary tumors that became the main reasons for initiating this study.
8 secondary outcomes
Overall survival
Time frame: 2 years
To evaluate the rate of transplant-associated mortality.
Time frame: 2 years
Number of Participants With Treatment-Related Adverse Events as Assessed by CTCAE v4.0
Time frame: 3 months
Probability of graft rejection
Time frame: 2 years
Frequency of Complete Donor and Mixed Chimerism after HSCT
Time frame: 1 year
Incidence of acute GVHD.
Time frame: 1 year
Incidence of chronic GVHD.
Time frame: 2 years
To assess the kinetics of immune reconstitution
Time frame: 1 year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Jan 2026.
- Individual participant dataSharing planned: No
Related trials for HSCT
Not yet recruitingObservational study
Prevalence and Development of Liver Dysfunction in Hematopoietic Stem Cell Transplant
Hematopoietic Stem Cell Transplant
Active, not recruitingPhase 1/2
A Window of Opportunity Trial to Learn if Linvoseltamab is Safe and Well Tolerated, and How Well it Works in Adult Participants With Recently Diagnosed Multiple Myeloma Who Have Not Already Received Treatment
Multiple Myeloma
RecruitingEarly Phase 1
HMCT/CT2401: Abatacept GVHD Prophylaxis Following Omidubicel HCT
Hematologic Malignancy
Active, not recruitingPhase 2
Clofarabine and Melphalan Before Donor Stem Cell Transplant in Treating Patients With Myelodysplasia, Acute Leukemia in Remission, or Chronic Myelomonocytic Leukemia
Adult Acute Lymphoblastic Leukemia in Remission, Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome
RecruitingObservational study
Natural History Study to Determine Drug Metabolism Phenotype and Appropriate Germline Source DNA in Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplant
Leukemia, Lymphoma
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Treosulfan (Treo) in people with HSCT and Nijmegen Breakage Syndrome, run by Federal Research Institute of Pediatric Hematology, Oncology and Immunology.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 5 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Dmitry Balashov, MD, PhD (+7-926-579-78-17, bala8@yandex.ru), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To evaluate event-free survival (EFS), defined by the occurrence of death, graft rejection, or development of secondary malignancy/relapse. (time frame: 2 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Jan 2026.