Choosing the right busulfan dose before transplant for infants with IL2RG, JAK3, or RAG1/2 SCID

Clinical and mechanistic studies defining optimal preparative approaches to infants with IL2RG/JAK3/RAG1/RAG2 SCID: a randomized trial of busulfan dosage

NIH-funded research National Marrow Donor Program · NIH-11378897

This project compares two chemotherapy (busulfan) dosing strategies to help infants with certain genetic forms of SCID regain their immune cells after a stem cell transplant.

Quick facts

Grant typeU01 cooperative agreement
Study typeNIH-funded research
Funding institutionNational Marrow Donor Program NIH-funded
Lab location1 site (Minneapolis, United States)
Project IDNIH-11378897 on NIH RePORTER

What this research studies

You would join a randomized program that gives infants one of two total busulfan exposure levels (cAUC 30 mg*h/L versus 60 mg*h/L) before an allogeneic stem cell transplant. Children with IL2RG or JAK3 mutations receive rabbit ATG, while those with RAG1/2 mutations receive rabbit ATG plus fludarabine and thiotepa as part of their preparative plan. Stem cells can come from unrelated donors or haploidentical (partially matched) family members, and the effort builds on an earlier CSIDE protocol. The goal is to see whether lower, individualized busulfan can allow both T and B cell recovery with less toxicity, and more than 50 transplant centers are open to enroll patients.

Who could benefit from this research

Good fit: Infants with severe combined immunodeficiency caused by IL2RG, JAK3, RAG1, or RAG2 mutations who are candidates for allogeneic hematopoietic cell transplantation are the intended participants.

Not a fit: Children with other causes of immune deficiency, older patients, or those receiving gene therapy instead of transplant are unlikely to benefit from this specific protocol.

Why it matters

Potential benefit: If successful, this approach could let infants regain both T and B cell immunity with less chemotherapy-related toxicity.

How similar studies have performed: Previous non-randomized work showed T cell recovery without high-dose busulfan but inconsistent B cell outcomes, and this randomized follow-up builds on that earlier CSIDE experience.

Where this research is happening

Minneapolis, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-10 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.