Impact of Selection of Cord Blood Units from the United States and Swiss Registries on the Cost of Banking Operations

Abstract

<b><i>Background: </i></b>Over the last 2 decades, cord blood (CB) has become an important source of blood stem cells. Clinical experience has shown that CB is a viable source for blood stem cells in the field of unrelated hematopoietic blood stem cell transplantation. <b><i>Methods: </i></b>Studies of CB units (CBUs) stored and ordered from the US (National Marrow Donor Program (NMDP) and Swiss (Swiss Blood Stem Cells (SBSC)) CB registries were conducted to assess whether these CBUs met the needs of transplantation patients, as evidenced by units being selected for transplantation. These data were compared to international banking and selection data (Bone Marrow Donors Worldwide (BMDW), World Marrow Donor Association (WMDA)). Further analysis was conducted on whether current CB banking practices were economically viable given the units being selected from the registries for transplant. It should be mentioned that our analysis focused on usage, deliberately omitting any information about clinical outcomes of CB transplantation. <b><i>Results:</i></b> A disproportionate number of units with high total nucleated cell (TNC) counts are selected, compared to the distribution of units by TNC available. Therefore, the decision to use a low threshold for banking purposes cannot be supported by economic analysis and may limit the economic viability of future public CB banking. <b><i>Conclusions:</i></b> We suggest significantly raising the TNC level used to determine a bankable unit. A level of 125 × 10<sup>7</sup> TNCs, maybe even 150 × 10<sup>7</sup> TNCs, might be a viable banking threshold. This would improve the return on inventory investments while meeting transplantation needs based on current selection criteria.

One-Unit versus Two-Unit Cord-Blood Transplantation for Hematologic Cancers

“…Therefore, the aim of the current trial was to determine the effect of the graft composition (double-unit vs. single-unit) on 1-year survival among patients who received the same conditioning and GVHD prophylaxis regimen as that used in the pilot study. 16 Since many adults would not have had an adequate single unit, conventionally defined as at least 2.5×10 7 nucleated cells per kilogram, 24 the current trial involved children, and an adequate single unit and adequate double unit were available for all the patients.…”

Challenges to the Sustainability of the U.S. Public Cord Blood System

“…[121][122][123][124][125][126] Not surprisingly, the likelihood of both CBU use and transplant success is greatest among high-TNC count units. 81,121,[127][128][129] Among all transplanted CBUs from NMDP data from 2007 to 2016, only 11 percent had a TNC count below 1.25×10 9 (see Figure 7.1). The share of transplanted CBUs, however, was 28 percent and 59 percent for CBUs with TNC counts of 1.25-1.75×10 9 and 1.75×10 9 or more, respectively.…”

“…The incentive for storing high-quality CBUs is relatively high because the use of the higher-TNC count CBUs currently generates about 70 percent of public CBBs' revenue. 127 However, this could change if cord blood cell expansion technologies someday render smaller units more effective for transplantation (see Chapter Eight for further discussion of this future possibility). 127 Similar ratios of released units relative to the banked inventory are observed in other countries, such as France, Italy, Germany, and Australia.…”

“…127 However, this could change if cord blood cell expansion technologies someday render smaller units more effective for transplantation (see Chapter Eight for further discussion of this future possibility). 127 Similar ratios of released units relative to the banked inventory are observed in other countries, such as France, Italy, Germany, and Australia. 130 These ratios are typically the smallest for banks with the largest inventories as a consequence of storing large numbers of low-quality units.…”

“…Another study suggested that if the TNC threshold was increased to 1.50×10 9 , the discard rate would be 92 percent. 127 The difference between these discard rates may be driven by the fact that ANCTC has staff dedicated to CBU collection, potentially allowing for higher TNCs on average due to larger volumes. Therefore, banks have to consider the trade-offs between having a higher release rate and higher-TNC count units and the number or rate of collected units that they will bank at the higher threshold.…”