Allogeneic stem cell transplantation for sickle cell disease

As the safety and availability of allogeneic hematopoietic stem cell transplantation (HSCT) have improved, this procedure is becoming a viable option for nonmalignant conditions such as sickle cell disease (SCD). There are very few treatment options available for SCD, and even with optimal care SCD patients still suffer from a myriad of comorbidities to multiple organ systems and have a decreased life span. In this review, we will summarize results from trials of HSCT for children or adults with SCD using a variety of graft sources as well as conditioning and graft-versus-host disease prophylaxis regimens, and discuss the unique challenges that arise in these patients.

AlloHSCT for SCD has been performed on small numbers of patients at multiple centers around the world using several different transplant platforms, and early outcomes are encouraging. Overall survival is excellent, although graft failure remains a challenge.

As alloHSCT becomes safer and more widely available, the procedure should be considered for patients with severe disease phenotypes in whom the potential benefits of transplantation outweigh the complications from the disease. AlloHSCT has been shown to reverse or at least halt the progression of end-organ damage secondary to SCD. More research is needed to understand the mechanisms underlying graft failure in SCD recipients, as well as to understand the biopsychosocial underpinnings of persistent pain in the posttransplant period to maximize the benefit from the transplant procedure.