Platelets: Frozen and Freeze-Dried Current Products in Development and Regulatory Licensing Challenges

Abstract

Cryopreserved and lyophilized platelets have a long, but limited, history of human use that dates back to the 1950s yet involves a small number of total study subjects (Fig. 9.1). Despite decades of research characterizing the quality and nature of these products, questions remain regarding the relationship between in vitro performance and in vivo function to control bleeding. That said, results to date indicate promising in vivo hemostatic potential in several animal models. Although the data is retrospective and cannot definitively establish causality, human use of cryopreserved platelets in military settings also appears to be associated with benefit. The regulatory pathway for these products, particularly in the case of cryopreserved platelets, has been decades long, and more trials are needed to provide high-quality data to regulatory bodies. These products could be life-saving in settings where other good alternatives are limited or unavailable.