NCT06358638

Sickle Cell Disease Transplant Using a Nonmyeloablative Approach for Patients With Anti-donor Red Cell Antibody

Sickle Cell Disease Transplant Using a Nonmyeloablative Approach: Adding Daratumumab for Patients With Anti-donor Red Cell AntibodY

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 12 (estimated)
• Sponsor: Children's National Research Institute · Academic / Other
• Sex: All
• Age: 2 Years – 25 Years
• Healthy volunteers: Not accepted

Summary

This multicenter prospective study seeks to determine if daratumumab given, prior to HLA-identical sibling donor transplantation using alemtuzumab, low dose total-body irradiation, and sirolimus, can prevent pure red blood cell aplasia with an acceptable safety profile in patients with anti-donor red blood cell antibodies, achieving an event-free survival similar to transplanted patients without such antibodies.

Detailed description

This study addresses an important question: Can daratumumab safely be administered prior to matched sibling donor (MSD) nonmyeloablative hematopoietic cell transplant (HCT) for SCD to avoid pure red blood cell aplasia in patients at risk of this complication? and thus achieve an event-free survival similar to patients without anti-donor red blood cell (RBC) antibodies? Patients with anti-donor RBC antibodies, which includes patients with major ABO mismatch and other RBC alloantibodies against donor, have largely been excluded from the nonmyeloablative HCT approach given their risk of delayed donor RBC engraftment and/or hemolysis post-HCT. Exclusion of these patients limits access to less toxic curative therapies for this population at risk for toxicity due to their underlying multisystem disease. To address this need, we propose a multicenter clinical trial of Sickle cell disease Using a Nonmyeloablative approach: adding daratumumab for patients with anti-donor Red cell AntibodY (SUN-RAY). If successful, this trial will increase access to MSD nonmyeloablative HCT in SCD and will provide important safety and efficacy data for the use of daratumumab in the pre-HCT setting as well as in patients with SCD who have limited RBC donor options due to alloimmunization. This is a phase 2 study given that the studied nonmyeloablative conditioning backbone (alemtuzumab, 300 cGY TBI, sirolimus) has been previously used effectively in both adults and children with SCD. Daratumumab will be added to this backbone with a washout period of 4 weeks prior to HCT infusion. Small case series have demonstrated that daratumumab is well tolerated either pre-HCT to treat patients with antibodies against mismatched donor HLA antigens, or post-HCT in patients with autoimmune cytopenias. The experience of the phase 2 clinical trial NCT03384654 studying daratumumab in pediatric acute lymphoblastic leukemia provides additional support for the safety and dosing of daratumumab for this study.

Conditions

• Sickle Cell Disease

Interventions

Type	Name	Description
DRUG	Daratumumab	Daratumumab is a cytotoxic monoclonal antibody (IgG1k) to CD38 and is commercially approved to treat multiple myeloma. CD38 is expressed on several types of blood cells including B-cells, antibody-secreting plasma blasts and plasma cells. As a result, it has been used to treat antibody-mediated diseases, including children with antibody-mediated cytopenias post-HCT.
DRUG	Alemtuzumab	Alemtuzumab is a humanized monoclonal antibody specific to lymphocyte antigens. It is a recombinant DNA-derived humanized monoclonal antibody (Campath-1H) that is directed against the 21-28 kD cell surface glycoprotein, CD52.
DRUG	Sirolimus	Sirolimus is an mTOR inhibitor immunosuppressant used to prevent organ transplant rejections as well as treat lymphangioleiomyomatosis and adults with perivascular epithelioid cell tumors.
RADIATION	Total Body Irradiation	Total body irradiation is a form of radiotherapy used primarily as part of the preparative regimen for haematopoietic stem cell transplantation. The radiation is given in a low dose so that normal tissues can repair themselves.

Timeline

• Start date: 2024-04-03
• Primary completion: 2044-09-01
• Completion: 2054-09-01
• First posted: 2024-04-10
• Last updated: 2025-09-26

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study