RH Genotype Matched RBC Transfusions

Children's Hospital of Philadelphia (CHOP)

Status and phase: Enrolling; Phase 2; Phase 1

Conditions: Sickle Cells Disease

Treatments: Biological: Red cell units that are genotype matched at the RHD and RHCE loci

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT04156893

19-016565

R01HL147879 (U.S. NIH Grant/Contract)

R01HL169401 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

To determine the feasibility and efficacy of matching donor red cells by RH genotype for a cohort of chronically transfused patients with SCD.

Full description

This is a Phase 1/2 trial in patients with Sickle Cell Disease requiring chronic red cell transfusions. RH genotyped donor units will be obtained from the New York Blood Center. Patients will be matched with donor units whose RH genotypes predict no foreign Rh protein exposure to the patient. This will provide red cell matching at a level above the current standard of care (serologic C, E, and K matching). Patients will receive RH matched red cells for the duration of their chronic transfusion therapy or up to three years, whichever is shorter. In the pilot phase, we have determined it is feasible to identify RH matched donor units for the patient's RH genotype for every scheduled transfusion. We will now continue to show feasibility as well as determine efficacy by monitoring Rh alloantibody formation.

For subjects with a history of stroke/recurrent transient ischemic attack or other indication who require tight control of Hb S, and RH genotyped blood is not available, standard of care serologic matched blood would be administered rather than delaying transfusion and risking higher Hb S level.

For all subjects, standard of care serologic matched blood would be administered rather than delaying transfusion beyond 7 days.

Enrollment: 35 estimated patients

Sex: All

Ages: 6+ months old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Subjects age >6 months
• Diagnosis of SCD, all genotypes
• Require a period of chronic red cell transfusion therapy
• Subject/parental/guardian permission (informed consent) and if appropriate, child assent

Exclusion criteria

• Rare RH genotype that would preclude identification of sufficient RBC units
• Antigen negative requirements due to alloimmunization that would preclude identification of sufficient RBC units
• Alloimmunized to D antigen
• Rh alloimmunized patients for whom providing RH genotype matched blood would expose the patient to an antigen that would not be consistent with standard of care and blood bank protocols
• Parents/guardians or subjects who, in the opinion of the Investigator, may be non-compliant with study schedules or procedures

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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35 participants in 1 patient group

RH genotype matched red cell transfusions

Experimental group

Description:

Subjects will receive RH genotyped matched red cell units for transfusion in addition to standard serologic C, E, and K antigen matching and being hemoglobin S negative, which is our institutional standard of care for patients with Sickle Cell Disease.

Treatment:

Biological: Red cell units that are genotype matched at the RHD and RHCE loci