Nationwide Centralized Manufacturing and Fresh Distribution of TCRαβ/CD19-DepletedGrafts: A Real-World French...

TCRαβ/CD19 depletion enables mismatched and haploidentical hematopoietic stem cell transplantation (HSCT) without the use of a post-transplant alkylating agent and is particularly relevant for pediatric nonmalignant disorders. However, the complexity of graft engineering limits its availability to specialized centers. Indeed, implementing such a process and obtaining regulatory approval are resource-intensive endeavors that require sufficient patient volume. To address these limitations, we established a centralized platform for the real-time nationwide distribution of fresh TCRα/β/CD19-depleted grafts in France, prioritizing bringing the cells to the patients, rather than the patients to the cells. This study aimed to evaluate the feasibility and challenges of this unique model of centralized, nationwide manufacturing of fresh TCRαβ/CD19-depleted grafts. In this retrospective cohort study (2014 to 2025), after on-site or off-site collections, all haploidentical or mismatched unrelated donors that underwent TCRα/β/CD19 depletion were manufactured at a single academic facility and delivered to nationwide transplant centers. Manufacturing performance, product compliance, logistics (vein-to-vein and delivery times), and early hematologic recovery were analyzed and compared for 10 transplant centers. A total of 55 products were distributed after undergoing TCRα/β/CD19 depletion for Inborn Errors of Immunity (n = 36), DNA repair/bone marrow failure (n = 15), and malignancies (n = 4). Despite significant heterogeneity in starting apheresis materials across different collection centers, manufacturing performance was robust and reliable, with comparable CD34+ recovery, TCRαβ, and CD19 depletion efficacy between on-site and off-site collections. Infused CD34 dose was similar between on-site and off-site apheresis (9.81 × 10⁶/kg versus 9.91 × 10⁶/kg), and TCRα/β doses were <1 × 10⁵ in 96% of products. Vein-to-vein time met the <36-h target in 52/55 cases (95%), including the majority of off-site collection and infusion procedures. Delivery time remained within the <6-h specification for all on-site infusions and 14/16 off-site infusions. Early neutrophil and platelet recovery were comparable between groups, with identical 50% recovery times of 15 days post-HSCT. Centralized fresh manufacturing and nationwide distribution of TCRαβ/CD19-depleted grafts are feasible, safe, and logistically robust. This approach represents a valuable intermediate model between local fresh production and centralized cryopreserved manufacturing, particularly in light of the reported limitations of cryopreservation on graft quality and immune effector cell integrity. It may provide a scalable organizational framework for other academic cellular therapy and ATMP platforms.