Evaluation of the post-transfusion platelet increment and safety of riboflavin-based pathogen reduction technology (PRT) treated platelet products stored in platelet additive solution for 5 days or less versus 6-7 days.

BACKGROUND AND OBJECTIVES: Platelets are stored routinely for 5 days or less and extended platelet storage time could improve product availability. This study compared platelet count increments (CI24hs) of riboflavin plus UV-light (PRT) treated platelet products in platelet additive solution stored for 5 days or less to products stored for 6-7 days. MATERIAL AND METHODS: This was a retrospective study comparing CI24hs between two groups. Hematology patients received PRT treated platelet products stored for <5 days, or for 6-7 days. Platelet counts and adverse events during and up to 24 hours after transfusion were recorded and compared between the groups. RESULTS: Ninety-seven patients received 168 transfusions of <5 day old PRT-treated platelets and 49 patients received 74 transfusions of 6-7 day old PRT-treated platelets. There was no statistically significant difference in CI24hs between the <5 day (median 6000) and 6-7 day storage group (median 8000) (p-value = 0.509). One mild fever was documented in the <5 day storage group. CONCLUSION: CI24hs are similar for PRT-treated PLTs stored in PAS for <5 or 6-7 days. Studies to further evaluate clinical outcomes such as bleeding are ongoing.

Mobilization of hematopoietic progenitor cells from allogeneic healthy donors using a new biosimilar G-CSF (Zarzio®).

Peripheral blood progenitor cells (PBPCs) have become the major source of hematopoietic progenitor cells for allogeneic transplantation. In February 2008, Zarzio® was approved by the European Medicine Agency for PBPCs mobilization, but this authorization was not based in trials analyzing safety and efficacy for PBPCs mobilization. Since August 2011, Zarzio® has been used at our institution for PBPCs mobilization. In total 36 healthy family donors underwent PBPCs mobilization, 18 with Neupogen® and 18 with Zarzio®. Donor characteristics were equivalent between groups, and no severe adverse effects were registered in the Zarzio® group. The number of CD34 cells collected/Kg recipient body weight was 6.7 × 10(6) (3.8-11.1) in the Zarzio® group versus 8.4 × 10(6) (5.6-16.6) in the Neupogen® group (P = 0.04). We collected the minimal target cell dose (2 × 10(6) /kg) in all donors from each group and no significant differences were found in the collection of the optimal cell dose (5 × 10(6) /kg) between groups, although 3/18 (16.6%) donors that received Zarzio® failed to mobilize the optimal cell dose compared with 0% in the Neupogen® group. A total of 35 patients proceeded to transplantation (17 in the Zarzio® and 18 in the Neupogen® groups, respectively). Platelet and neutrophil median time to engraftment was comparable between the two groups. Our retrospective study supports the conclusion that Zarzio® mobilization of PBPCs in healthy donors is safe but perhaps not as effective as the reference Neupogen. However, more prospective trials are required to definitively asses the safety and efficacy of G-CSF biosimilars for PBPCs mobilization in healthy donors.