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Neither COVID-19 nor cryopreservation prevented access to lifesaving stem cell transplantation

Desperate times call for desperate measures. There’s no doubt that the COVID-19 pandemic qualifies as desperate times. And there’s no doubt that the measures the National Marrow Donor Program (NMDP) took to ensure that lifesaving cellular therapy proceeded uninterrupted were an unqualified success.

In normal times, bone marrow and peripheral blood stem cells are harvested, hand couriered and infused fresh into patients at the time of transplant more than 90% of the time. 

Desperate times, desperate measures

The pandemic changed all that. Transportation delays, travel barriers and supply chain issues combined to make it impossible to reliably deliver fresh marrow and stem cell products. Cryopreservation, or freezing, of the products was necessary to ensure that lifesaving grafts were available at the time of patient need. A recent study from the Center for International Blood and Marrow Transplantation (CIBMTR), a research collaboration between the NMDP and Medical College of Wisconsin, demonstrated that use of cryopreserved products during the pandemic didn’t negatively affect patient outcomes when compared to fresh products before the pandemic. This data provides reassurance that cryopreservation can be safely and effectively used when necessary, without compromising patient care. 

The NMDP evaluated the usage of 9,294 bone marrow and peripheral blood stem cell products from both unrelated (94.5%) and related (5.4%) donors in the U.S. and other countries and collected between March 2020 and June 2021. As of August 2021, 8,700, (93.6%) of the products had been infused. 

Because cryopreserved products don’t have to be infused immediately, some of the bone marrow and peripheral blood stem cells collected during that time are pending infusion — 374 (4%). Only 220 products (2.4%) weren’t used. To put that in perspective, in normal — pre-pandemic — times, about 1% of products aren’t infused, mainly due to a deterioration in patient condition that prevents proceeding to transplant.  This is a notably low non-usage rate given the circumstances and speed in which the switch to cryopreservation occurred. 

Another finding in the analysis was that donor COVID-19 positivity did not increase patient risk. Among the more than 9,000 donors, 34 tested positive for COVID-19 before or after donating. In 13 cases, collection from donors was stopped due to COVID-19 positivity. Among patients who received an infusion from a donor who had tested positive, none developed a COVID-19 infection or experienced other negative effects on engraftment — even when the donor developed COVID within a week of donation.

The bottom-line — a silver lining to a dark cloud

The results of this observational study by the NMDP can help guide transplant and donor centers in decision-making during future desperate times, including times when blood and marrow products must be cryopreserved. And people in need of transplants can rest easy that even during desperate times, the lifesaving care they need won’t have to wait. The knowledge we now have about the efficacy of cryopreservation and the flexibility it offers is a silver lining to the dark cloud of the pandemic.

Learn more by reviewing a comprehensive analysis and description of the study.

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Heather E Stefanski (PI) 
Jeni Newman
Jennifer Novakavich
JJ Barten
Jason D. Oakes
Meghann Cody
Jeffrey A. Auletta
Huy Pham
John Miller
Steven M. Devine