An observational study in Sickle Cell Disease, Thalassemia and Pediatric Cancer, sponsored by Westat. Completed at 14 sites in 2 countries. Per ClinicalTrials.gov, last updated 2024-05-17.
Sponsored by Westat · Observational
Red Blood Cell - IMProving trAnsfusions for Chronically Transfused recipients (RBC-IMPACT) is an observational cohort study to assess donor, component, and recipient factors that contribute to RBC efficacy in chronically and episodically transfused patients. The objective of the study is to determine how specific genetic and non-genetic factors in donors and recipients may impact RBC survival after transfusion - in short, what factors on both the donor and recipient side may improve the efficacy of the transfusion.
Sickle cell disease (SCD) and thalassemia are genetic disorders inducing anemia of differing pathophysiology. A primary therapy for preventing certain SCD complications (e.g., stroke) and for thalassemia major is regular red blood cell (RBC) transfusion, coupled with iron chelation to prevent the complications of transfusion-induced iron overload. For patients with pediatric hematology-oncology diagnoses with chemotherapy-induced aplasia, RBC transfusion is also common, but the degree of transfusion-induced iron overload and its implications for these patients is incompletely understood. Because iron-related tissue toxicity is a major cause of morbidity and mortality in regularly transfused patients, developing strategies to minimize iron loading and iron toxicity is a key objective of this proposal (study Aim #2), stemming from the objective to optimize RBC unit characteristics that patients with SCD and thalassemia receive beyond RBC phenotype matching for Rh C, E and K antigens (study Aim #1). The study will enroll patients with SCD, thalassemia or pediatric oncologic diagnoses receiving eligible transfusion at 6 hospital sites in the United States, as well as patients with SCD at 5 hemocenters in Brazil.
1,134 studies on the registry are indexed under Anemia, Sickle Cell; 238 are open to participants now.
This study's enrollment of 157 is above the median of 100 across 296 observational studies indexed under Anemia, Sickle Cell.
Browse Anemia, Sickle Cell studies →Westat is the lead sponsor of 23 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
All transfused patients with sickle cell disease (in the U.S or Brazil) and thalassemia on simple chronic transfusion (or partial manual exchange transfusion) from hospitals affiliated with REDS-IV-P Domestic hubs or Brazil hemocenters. (Aim #1)
Chronically transfused patients with sickle cell disease or thalassemia, and patients with pediatric oncology diagnoses with hypo-proliferative bone marrow receiving care at hospitals affiliated with REDS-IV-P Domestic hubs or Brazil hemocenters (for SCD only). (Aim #2).
Inclusion Criteria (Aim #1):
Exclusion Criteria (Aim #1):
Inclusion criteria (Aim #2):
Exclusion criteria (Aim #2):
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients with SCD who are chronically transfused (in the U.S. and Brazil)
Biological: Red Blood Cell (RBC) Transfusion
Patients with thalassemia who are chronically transfused in the U.S.
Biological: Red Blood Cell (RBC) Transfusion
Patients in U.S. with pediatric oncologic diagnoses with hypo-proliferative bone marrow requiring single unit red blood cell transfusion
Biological: Red Blood Cell (RBC) Transfusion
Allogenic blood donors in the US (estimated: 10,200) and allogenic blood donors in Brazil (estimated: 2,100) with extended donation genotyping using an investigational hematology array.
Simple RBC transfusion or partial manual exchange
Change in Hemoglobin A or Hemoglobin Level per day (RBC Survival)
Change in hemoglobin A or hemoglobin level per day in between subsequent transfusion episodes, for sickle cell disease and thalassemia cohorts, respectively
Time frame: Baseline (immediately pre-) to post-transfusion over 2 years
Change in Serum Iron Level
For all groups participating, change in serum iron measured from immediately prior to 2 hours post-transfusion
Time frame: Baseline (immediately before) and 2-hours after transfusion
Hemoglobin Increment
Hemoglobin increment \[defined as Hb/HbA(post-transfusion)visit(i) - Hb/HbA(pre-transfusion)visit(i)\] is associated with "RBC survival"
Time frame: Baseline (immediately pre-) to post-transfusion, over 2 years
Hemolysis Parameter Increment
Includes serum iron, indirect bilirubin, or plasma free hemoglobin
Time frame: Baseline (immediately pre-) to post-transfusion or 2-hours post-transfusion, over 2 years
Hepcidin Level
Hepcidin level at time of transfusion is a predictor of change in iron parameters (i.e., transferrin saturation, serum iron) following transfusion
Time frame: Baseline (immediately before) to 2 hours after transfusion
Non-Transferrin-Bound Iron (NTBI) Level
NTBI levels in patients with pediatric oncologic diagnoses with aplasia are elevated at baseline and increase following transfusion
Time frame: Baseline (immediately before) to 2 hours after transfusion
Number of Clinical Complications
Increased NTBI, serum iron, or transferrin saturation following transfusion is associated with increased risk of clinical adverse effects (i.e., new infections, SCD complications)
Time frame: 2 years
Rate of Alloimmunization
Rate of new alloantibody formation
Time frame: 2 years
4-hydroxynonenal [4-HNE]
Recipient oxidative stress pre-transfusion is associated with "RBC survival"
Time frame: 2 years
Type I interferon (i.e., MxA protein assay) and other cytokines (i.e., IL-6, MCP-1, IFNgamma)
Recipient inflammation pre-transfusion is associated with "RBC survival"
Time frame: 2 years
Number of Transfusion Reactions
Transfusion reactions are associated with "RBC survival"
Time frame: 2 years
Plan to share: Yes — De-identified public use datasets will be created and delivered to NHLBI at the end of the study (and end of the REDS-IV-P program) and will be made available indefinitely for future analysis
Supporting information: Study protocol, Clinical study report
Time frame: At the end of the REDS-IV-P program, estimated in March 2026, the public use data sets will be available and will be available indefinitely for future analytic use.
Access criteria: Public use datasets will be posted to NIH/NHLBI data repository systems.
Ran from Mar 2022 to primary completion in Mar 2024, 24 months.
Of 130 non-industry observational studies under Anemia, Sickle Cell, half reached primary completion within 48 months of starting (the median), counting those still running; a quarter within 23 and three quarters within 109. This study's 24 months is below that.
Counting every sponsor, half of 139 studies reached it within 49 months; a quarter within 24 and three quarters within 109.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2024. You cannot join it, but the record below documents what was studied.
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