Cryopreserved hematopoietic stem/progenitor cells stability program‐development, current status and recommendations: A brief report from the AABB‐ISCT joint working group cellular therapy product stability project team

Abstract

Background The AABB‐ISCT Joint Working Group Stability Project Team (SPT) was assigned to roadmap a path toward standardization of cryopreserved hematopoietic stem/progenitor cell (HSPC) stability programs. HSPC stability encompasses a broad scope of conditions including non‐frozen (“fresh”) and cryopreserved cell products, and varying methods for storage, thaw, and administration. This report assessed current practices and focused solely on cryopreserved HSPC cell therapy products to establish preliminary recommendations for a stability program roadmap. Methods A survey was prepared by the SPT and distributed to ISCT and AABB members. Survey results were summarized and recommendations were outlined based on the responses from the survey. This report highlights current practices for cryopreserved HSPC stability programs, including additional considerations and recommendations. Results and Discussion Eighty‐two (82) centers worldwide participated in the survey. Survey results indicate variability across programs. HSPC stability depends on multiple factors within the processing facility (e.g., cryopreservation techniques, reagents used, and storage temperature) and independent variables (e.g., donor‐related factors and starting material variability). While retention of hematopoietic engraftment potential is the primary goal for cryopreserved HSPC stability, engraftment results should not be used as the sole metric for stability programs. Based on the survey results, the SPT provides recommendations for consideration. Conclusions The SPT recommendations for best practices are not intended to replace existing standards. The survey results emphasize the need for the community to optimize best practices and consider initiating collaborative projects to improve the standardization of cryopreserved HSPC stability programs for cell therapy products.

Effects of extended transport on cryopreserved allogeneic hematopoietic progenitor cell (HPC) product quality and optimal methods to assess HPC stability

“…Still, meaningful viability and cell recovery thresholds for successful engraftment have also not been firmly established, rendering clinical judgments based on these values challenging. Additionally, though voluntary accreditation organizations, such as the Association for the Advancement of Blood & Biotherapies (AABB) and the Foundation for the Accreditation of Cellular Therapy (FACT), require a written HPC stability program for cryopreserved products, 15,16 a lack of a consensus test to predict HPC engraftment was noted by the AABB‐International Society for Cell Therapy (ISCT) Joint Working Group Stability Project Team to contribute to the challenges of establishing such a program 17 …”

“…Additionally, though voluntary accreditation organizations, such as the Association for the Advancement of Blood & Biotherapies (AABB) and the Foundation for the Accreditation of Cellular Therapy (FACT), require a written HPC stability program for cryopreserved products, 15,16 a lack of a consensus test to predict HPC engraftment was noted by the AABB-International Society for Cell Therapy (ISCT) Joint Working Group Stability Project Team to contribute to the challenges of establishing such a program. 17 Together, the uncertainties surrounding cryopreserved HPC product testing, viability, and potency have raised several concerns amongst transplant programs, with many now hesitant about its use for allogeneic transplantation. As the interruptions wrought by the pandemic continue, we sought to inform the field by conducting a retrospective analysis of HPC products processed at the National Institutes of Health (NIH), including both those collected by the NMDP and onsite, to determine the impact of extended transport on cryopreserved graft quality and engraftment.…”