What are the Realities to Consider as We Think About Implementing Pathogen Reduction of Platelets in the U.S.? (1)
The transfusion medicine community welcomes approval of Cerus's Intercept Blood System for pathogen-reduced (PR) platelets. It is an important safety step that will nearly eliminate bacterial contamination episodes, and be particularly valuable if paired with decreased testing, increased shelf-time, and the elimination of product irradiation. It is a first step to future PR systems that will be easier to use.
As transfusion medicine physicians, we have heard concerns about adverse clinical and operational outcomes, the real importance of which only experience will tell us. The former include lower corrected count increments (CCIs) after transfusion that may require more platelet transfusions (as in the SPRINT trial), more days of high grade bleeding (as in a meta-analysis by EC Vamvakas; a second one available here), a potential need for more red blood cell (RBC) transfusions (as presented in IPTAS Study in AABB Annual Meeting Abstract P2-030A), and concern with the long term safety of S-59, the active chemical agent in Intercept. Operational concerns relate to process-associated product loss and tight procedural guard bands (e.g., product platelet counts) that will certainly require increased platelet collections to maintain a robust platelet supply.
Future regulatory approvals may address these concerns. First, seven-day storage will decrease outdates and thus collection requirements. Next, an expeditious approval for use on triple collections will maximize products available for Intercept treatment. Based on the product information and expected platelet losses during processing, platelet counts at collection have to be higher, which decreases the split rate for current processes at New York Blood Center by 10 percent. Finally, approval of PR in platelets stored in plasma (vs. platelet additive solution) and from all collection platforms (i.e., Terumo BCT and Haemonetics) will simplify its adoption, reducing the required changes for clinicians and collection facilities. Lastly, approval for use with pooled whole blood derived platelets will expand PR to all platelets transfused in the U.S.
With PR of all components (RBCs, cryoprecipitate, platelets, and plasma), we should be able to decrease donor screening and still mitigate recognized and emerging infectious risks, and retire the cesium gamma radiation sources that create security and regulatory headaches. Short of these additional approvals and resulting efficiencies, hospital blood banks may rather keep costs in-house by performing point-of-release platelet bacterial testing, or may opt for delayed, high-volume cultures from their supplier in lieu of PR to make seven-day platelets available.
In the era of risk-informed decision-making and constrained resources, each physician and organization must balance cost with donor and patient outcomes. We have the beginnings but have to admit we are far from making the case to all stakeholders for universal adoption of platelet PR.
Louis Katz, MD; Chief Medical Officer; firstname.lastname@example.org
Beth Shaz, MD; Chief Medical Officer; NEw YOrk Blood Center; BShaz@nybc.org