Haploidentical Stem Cell Transplant for Patients With Sickle Cell Disease and Prior Stroke or Abnormal Transcranial Ultrasound

Sickle Cell Disease Clinical Trial

Official title: Hematopoietic Stem Cell Transplantation for Patients With Sickle Cell Disease and Prior Stroke or Abnormal Transcranial Doppler Ultrasound Using Reduced-Intensity Conditioning and T-Cell Depleted HSC From Partially Matched Family Donors

Status Completed

Clinical Trial Summary

Sickle cell disease is a life-long blood condition that can cause damage to the brain and other organs of the body. Children may develop severe, debilitating clinical states, with stroke or abnormal blood flow to the brain. Treatment generally includes chronic blood transfusions which may cause iron overload, potentially leading to severe and sometimes fatal complications.

Hematopoietic stem cell transplant using cells obtained from a sibling or an unrelated volunteer donor who is a perfect HLA "match" (same tissue type) for the recipient has shown to help, and possibly cure, sickle cell disease. Unfortunately, only about 10-20% of sickle cell patients have a HLA matched sibling donor, and the likelihood of locating an appropriate HLA matched unrelated donor through the various donor registries is limited.

Stem cells from partially HLA matched family members (also called haploidentical transplant) is an option currently being explored for this patient population. This type of transplant has been used and found to be successful in some patients, mostly those with cancers of the blood. However, there can be significant complications with haploidentical transplant, primarily infection, failure of the graft to grow (graft failure), and a disorder called graft-versus-host disease. In addition, few patients with sickle cell disease have undergone this procedure. Therefore, the risks and benefits of haploidentical transplants for patients with sickle cell disorder are not as well established as those using an HLA identical sibling or unrelated donor.

The primary objective of this study is to assess the safety of haploidentical stem cell transplantation for children and adolescents with severe sickle cell disease and stroke or abnormal transcranial Doppler ultrasound requiring chronic transfusion therapy. The treatment plan will be considered safe if there is not excessive toxicity. Toxicity for this protocol is defined as graft failure/graft rejection, severe acute GVHD, or regimen related death within 100 days after the last cellular product administered.

Of note, the protocol was closed to accrual in September 2007 as we had met the stopping rules related to graft integrity (graft failure and graft rejection). Participants currently enrolled continue to be followed per protocol.

Clinical Trial Description

Secondary objectives for this protocol include the following:

• To estimate 1-year overall and event free survival after transplantation. An event is defined as toxicity (graft failure, death, grade III/IV acute GHVD), or a sickle-related event (stroke, acute chest syndrome, pain crisis).

• To obtain preliminary information regarding donor engraftment among different cell subsets, including unsorted mononuclear cell, and lymphoid fractions during the first year after transplant.

• To observe the rate of acute and chronic GVHD during the first year after transplant.

• To assess the proportion of research participants who experience poor graft integrity and therefore require additional donor stem cells or lymphocytes.

• To document the effect of stem cell transplant on the central nervous system as defined by radiological imaging and neuropsychological testing.

• To investigate immune reconstitution after transplantation ;

Related Conditions & MeSH terms

• Anemia, Sickle Cell
• Sickle Cell Disease

• NCT number: NCT00152113
• Study type: Interventional
• Source: St. Jude Children's Research Hospital
• Status: Completed
• Phase: Phase 1
• Start date: April 2005
• Completion date: January 2009