Novel platelet products, substitutes and alternatives.

Despite the many advances in the safety, processing, and storage of conventional 22 degrees C liquid-stored allogeneic platelet concentrates, there still are significant drawbacks to the use of such products. Efforts to overcome these shortcomings have resulted in an array of novel platelet products, substitutes, and alternatives; which are currently at various stages of development. This review summarizes the recent developments in the frozen and cold storage of platelets; their pathogen inactivation; as well as the status of lyophilized platelets, infusible platelet membranes (IPMs), red cells bearing arginine-glycine-aspartic acid (RGD) ligands, fibrinogen-coated albumin microcapsules, and liposome-based agents; as potential alternatives to the use of conventional platelet transfusions. Pre-clinical studies have been encouraging for several of these novel products; however, to date, very few have entered human trials. Nonetheless, with the ongoing development of diverse products, those properties that may be necessary for their hemostatic effectiveness will become apparent. However, safety and efficacy must be demonstrated in pre-clinical and phase I to III clinical trials before these novel agents, substitutes and alternatives can be used clinically for patients with thrombocytopenia.