A Stanford Medicine research team has developed an innovative stem cell transplant conditioning regimen that replaces traditional chemotherapy and radiation with antibody therapy, offering a safer treatment option for patients with Fanconi anemia. The study, published in Nature Medicine and co-led by Assistant Professor Agnieszka Czechowicz and Professor Rajni Agarwal, achieved remarkable results in three pediatric patients.

The approach uses the anti-CD117 antibody briquilimab combined with modified donor cell processing to successfully perform stem cell transplants. Czechowicz stated: "We completely avoided radiation and the genotoxic chemotherapeutic agent busulfan used in conventional regimens." Two-year follow-up showed donor cell chimerism approaching 100% in all patients—far exceeding the researchers' target of 1%.

The regimen specifically clears the patient's own hematopoietic stem cells using the antibody while employing α/β T-cell-depleted haploidentical transplantation, reducing treatment toxicity and expanding the donor pool. The first patient treated—an 11-year-old boy named Ryder Beck—has shown dramatic health improvement post-transplant and has returned to normal school and sports activities.

The team is currently conducting a larger Phase II clinical trial and plans to extend the approach to other inherited blood disorders, such as Diamond-Blackfan anemia. This innovation provides a new treatment possibility for patients who require stem cell transplantation but cannot tolerate conventional conditioning regimens.