Usefulness of pegfilgrastim for allogeneic peripheral blood stem cell collection from healthy donors

Abstract Background Granulocyte colony‐stimulating factor (G‐CSF)‐based mobilization is essential for peripheral blood stem cell (PBSC) collection for allogeneic transplantation. Conventional daily G‐CSF requires repeated dosing and dose adjustment and often necessitates leukapheresis over multiple consecutive days, increasing donor burden. Single‐dose pegfilgrastim has emerged as an alternative; however, real‐world data on its impact on CD34 + cell collection in healthy donors remain limited. Study Design and Methods Healthy related or unrelated donors who received either a single dose of pegfilgrastim or daily filgrastim and subsequently underwent PBSC collection at Kyoto University Hospital between July 2014 and September 2025 were included. CD34 + cell harvest outcomes and donor burden were compared. Results A total of 39 donors were analyzed (20 pegfilgrastim, 19 filgrastim), with comparable baseline characteristics. At the start of leukapheresis, peripheral blood white blood cell counts were significantly higher in the pegfilgrastim group. Pegfilgrastim achieved greater total CD34 + cell yield (median 398.0 × 10 6 vs. 302.4 × 10 6 cells, p = .025) and higher yields per 10 L of processed blood (median 407.8 × 10 6 vs. 302.4 × 10 6 cells, p = .032). Single‐session leukapheresis was more frequent with pegfilgrastim (95.0% vs. 63.2%, p = .002), and the estimated processing time required to collect 2 × 10 6 /kg CD34 + cells was shorter (median 62.7 vs. 111.1 min, p = .040). No severe adverse events were observed. Discussion These findings suggest that single‐dose pegfilgrastim enables more efficient PBSC collection with reduced donor burden and may represent a practical mobilization strategy in healthy allogeneic donors.