Haplo-identical Hematopoietic Stem Cell Transplantation Following Reduced-intensity Conditioning in Children With Neuroblastoma

Overview

To date, no curative option exists for patients with relapsed or refractory stage IV neuroblastoma after previous autologous stem cell transplantation. Our preliminary results of RIC allo-HSCT (protocol RICE) indicate the feasability and low toxicity of allograft in heavily pre-treated children. Furthermore RIC SCT and immunomagnetic CD3/CD19 graft depletion may allow HHCT with lower toxicity and faster engraftment. CD3/CD19 depleted grafts not only contain CD34+ stem cells but also graft-facilitating cells, CD34- progenitors, dendritic and natural killer cells which may allow stable engraftment and participate to GvT effect. After haploidentical stem cell transplantation anti tumour activity exerted by donor derived NK cells could be stimulated by NK cells injections. Those effects may help to reduce the relapse rate and to impove the outcome of those patients. The investigators prospectively evaluated engraftment and immune reconstitution.

This RICE NK protocol is a multicenter study of Haplo- HSCT using RIC with fludarabine (180 mg/m2), Busulfan IV (3,2 to 4,8 mg/kg/d), TBI 2 grays and CD3/CD19 graft depletion. A minimum of 8 106 CD34+ cells/kg were infused on day 0. No post grafting immunosuppression was applied if the graft contained \< 2.5 x 104 CD3+ cells/kg. At Day 30 and 60 post-graft we perform an donor CD56+ cells injection. The investigators develop this strategy in an European collaboration working on haploidentical stem cell transplantation for childhood refractory and metastatic solid tumors.

Conditions