Citrate Versus Citrate–Heparin Anticoagulation in <scp>HPC</scp> (A): Comparative Effects on Intra‐Apheresis Mobilization of <scp>CD34</scp> ⁺ Hematopoietic Progenitor Cells

Successful hematopoietic stem cell transplantation relies on the collection of a sufficient number of CD34⁺ hematopoietic progenitor cells (HPCs). While acid citrate dextrose solution A (ACD-A) is a common anticoagulant (AC) for HPC apheresis [HPC(A)], recent evidence suggests that concomitant heparin may enhance intra-apheresis recruitment (IAR) of CD34⁺ cells and improve collection efficiency. This study aimed to compare citrate-only and citrate-heparin protocols in routine HPC(A) procedures, with a focus on their effects on IAR and efficiency outcomes. A retrospective analysis was performed on 266 HPC(As) from 193 apheresis donors in autologous and allogeneic settings. Donor demographics, procedural parameters, and collection outcomes were compared between the ACD-A-only and ACD-A plus heparin protocols. The study endpoints included apheresis yield (AY/kg), collection efficiencies (CE₁, CE₂, and cruCE), recruitment ratio (RR), and performance ratio (PR). Statistical analyses included Mann-Whitney U tests, effect sizes, and partial least squares (PLS) regression. Heparinized procedures demonstrated higher processed total blood volume ratios, lower AC volumes, and superior outcomes across CE₁ (83.8% vs. 72.5%, p = 0.00027), CE₂ (70.8% vs. 64.2%, p = 0.0055), cruCE (77.0% vs. 72.4%, p < 0.0001), RR (2.3 vs. 1.7, p < 0.0001), PR (239.3% vs. 208.2%, p < 0.0001), and AY/kg (6.75 vs. 5.23 × 10⁶ CD34⁺ cells/kg, p = 0.0025). The effect size and PLS analyses confirmed the contribution of heparin as an adjunct AC enhancing multiple apheresis outcomes. In summary, citrate-heparin anticoagulation was found to be a feasible strategy that improved key collection efficiency and IAR metrics during HPC(A).