RH Genotype Matched RBC Transfusions
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Red cell units that are genotype matched at the RHD and RHCE loci.
- Who it may be relevant to
- Registry conditions: Sickle Cells Disease. Basic parameters: from 6 months · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
RH Genotype Matched Red Cell Transfusions for Patients With Sickle Cell Disease
Overview
To determine the feasibility and efficacy of matching donor red cells by RH genotype for a cohort of chronically transfused patients with SCD.
Detailed 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.
Interventions
- Biological Red cell units that are genotype matched at the RHD and RHCE loci
Patients will be provided with red cell units that are C, E, and K antigen matched (standard of care for patients with SCD) and genotype matched at the RHD and RHCE loci.
Primary outcome measures
- Determine the treatment efficacy by monitoring the rate of Rh alloimmunization [Time frame: 3.5 years]
- Determine the feasibility of identifying sufficient RH genotype matched units [Time frame: 3.5 years]
Secondary outcome measures (1)
- Determine the rate of non-Rh alloimmunization [Time frame: 3.5 years]
Eligibility criteria
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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
United States · 1 center
- Children's Hospital of Philadelphia — Philadelphia
Publications
- Chou ST, Jackson T, Vege S, Smith-Whitley K, Friedman DF, Westhoff CM. High prevalence of red blood cell alloimmunization in sickle cell disease despite transfusion from Rh-matched minority donors. Blood. 2013 Aug 8;122(6):1062-71. doi: 10.1182/blood-2013-03-490623. Epub 2013 May 30. PMID 23723452
- Vichinsky EP, Earles A, Johnson RA, Hoag MS, Williams A, Lubin B. Alloimmunization in sickle cell anemia and transfusion of racially unmatched blood. N Engl J Med. 1990 Jun 7;322(23):1617-21. doi: 10.1056/NEJM199006073222301. PMID 2342522
- Yawn BP, Buchanan GR, Afenyi-Annan AN, Ballas SK, Hassell KL, James AH, Jordan L, Lanzkron SM, Lottenberg R, Savage WJ, Tanabe PJ, Ware RE, Murad MH, Goldsmith JC, Ortiz E, Fulwood R, Horton A, John-Sowah J. Management of sickle cell disease: summary of the 2014 evidence-based report by expert panel members. JAMA. 2014 Sep 10;312(10):1033-48. doi: 10.1001/jama.2014.10517. PMID 25203083
- Chou ST, Evans P, Vege S, Coleman SL, Friedman DF, Keller M, Westhoff CM. RH genotype matching for transfusion support in sickle cell disease. Blood. 2018 Sep 13;132(11):1198-1207. doi: 10.1182/blood-2018-05-851360. Epub 2018 Jul 19. PMID 30026182
- Coleman S, Westhoff CM, Friedman DF, Chou ST. Alloimmunization in patients with sickle cell disease and underrecognition of accompanying delayed hemolytic transfusion reactions. Transfusion. 2019 Jul;59(7):2282-2291. doi: 10.1111/trf.15328. Epub 2019 Apr 25. PMID 31021439
- Mewha J, Vege S, Friedman DF, Makrm S, Ochoa G, Westhoff CM, Chou ST. Red cell antigen exposures in patients with sickle cell disease receiving transfusion from Black and Hispanic donors. Blood Red Cells Iron. 2026 Jun;2(2):100059. doi: 10.1016/j.brci.2026.100059. Epub 2026 Apr 8. PMID 42376265
Identifiers
NCT: NCT04156893 · 19-016565 · R01HL147879 · R01HL169401