A Phase 2 interventional study of Treosulfan and Busilvex in Primary Immunodeficiencies, Inborn Errors of Metabolism and Haemoglobinopathies, sponsored by medac GmbH. Completed at 21 sites in 4 countries. Open to participants aged 28 Days to 17 Years. Per ClinicalTrials.gov, last updated 2025-12-08.
Sponsored by medac GmbH · Phase 2, Interventional, and Treatment
The aim of the trial is to describe the safety and efficacy of intravenous (i.v.) Treosulfan compared to the conventional (myeloablative) dose of i.v. Busulfan, each administered as part of a standardised Fludarabine-containing conditioning regimen and to contribute to a PK model which permits - in conjunction with data comparing Treosulfan and Busulfan in adults with malignant diseases - to extend the use of Treosulfan in the paediatric population by extrapolating efficacy.
The prospective clinical phase II protocol MC-FludT.16/NM is to be conducted to verify safety and efficacy of Treosulfan-based conditioning compared to Busulfan-based conditioning in paediatric patients. Based on the given clinical experience with either Treosulfan-based or Busulfan-based conditioning in combination with Fludarabine no increased risk for graft failure is expected in paediatric patients. A potential benefit for study patients is expected with respect to a probably low non-haematological toxicity of treatment compared to myeloablative TBI-based conditioning or high-dose Busulfan-based conditioning in combination with Cyclophosphamide.
However, the allogeneic HSCT procedure itself potentially involves serious risks with regard to severe or life-threatening conditions like graft versus host disease (GvHD) and/or infectious complications as well as graft failure.
In summary, the primary goal of this study is to evaluate the Treosulfan-based myeloablative conditioning regimen as an alternative in children and to contribute to the current PK model for Treosulfan to be able to finally give age (or body surface area [BSA]) dependent dose recommendations. The treatment regimens given in the protocol MC-FludT.16/NM are based on sufficient clinical safety and efficacy data. Considering the vital indication for allogeneic HSCT of the selected patient population, the risk-benefit assessment seems to be in favour of the study conduct.
Moreover, planned interim analyses will ensure the early identification of unexpected risks. Therefore, the conduct of the protocol MC-FludT.16/NM is considered reasonably justified.
152 studies on the registry are indexed under Metabolism, Inborn Errors; 22 are open to participants now.
This study's enrollment of 106 is above the median of 26 across 89 interventional studies indexed under Metabolism, Inborn Errors.
Browse Metabolism, Inborn Errors studies →medac GmbH is the lead sponsor of 22 studies on the registry; 2 are open to participants now.
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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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
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.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
One Treosulfan dose per day administered i.v. on three consecutive days (-6, -5 and -4); given over 2 hours as part of background conditioning prior to allogeneic stem cell transplantation. The dose has to be calculated as follows: If the BSA (m2) is equal or less than 0.3, the Treosulfan dose should be 10g/m2/day. If the BSA (m2) is greater than 0.3 and equal or less than 0.8, the Treosulfan dose should be 12g/m2/day. If the BSA (m2) is greater than 0.8, the Treosulfan dose should be 14g/m2/day.
Drug: Treosulfan
Total daily Busilvex dose (3.2 to 4.8 mg/kg/day, based on body weight) according to authorised dosage for children and adolescents administered i.v. as part of the background conditioning regimen on four consecutive days (days -7, -6, -5 and -4); given in 1, 2, or 4 portions per day according to the respective hospital's standard.
Drug: Busilvex
Comparative evaluation of freedom from transplant (treatment)-related mortality (TRM), defined as death from any transplant-related cause from the day of first administration of study medication (day -7) until day +100 after HSCT.
Time frame: day -7 to day +100
Plan to share: Undecided
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Studies of the drug tested here: Treosulfan