In Focus
Lyophilised platelets
Expanding the frontiers of transfusion and haemostatic support
Platelet transfusion is a critical component of modern haemostatic care for patients with thrombocytopenia, trauma, surgical bleeding, and haematological disorders, but the availability and utility of platelet products are often limited by storage and shelf-life constraints.
Conventional platelet concentrates typically have a shelf life of 5–7 days, largely due to the risk of bacterial proliferation during room-temperature storage and the progressive loss of platelet quality over time. In addition, their susceptibility to bacterial contamination and high rates of wastage can contribute to supply shortages and significant logistical challenges, particularly in remote and emergency care settings.
Lyophilised (freeze-dried) platelets are a promising alternative capable of overcoming many of these limitations. By enabling long-term storage, ambient-temperature distribution, and rapid reconstitution when required, lyophilised platelet products offer potential advantages for both clinical use and inventory management. As a result, considerable research efforts are focused on developing safe, effective, and standardised lyophilised platelet products as next-generation haemostatic therapies.
The role of platelets in haemostasis and transfusion
Platelets play a central role in primary haemostasis through adhesion, activation, and aggregation at sites of vascular injury. In addition to their haemostatic function, platelets contribute to inflammatory and immune responses and mediate interactions with the vascular endothelium.
Clinically, platelet transfusions are widely used to prevent bleeding in patients with severe thrombocytopenia, manage active haemorrhage in trauma or surgical settings, and support patients receiving chemotherapy or stem cell transplantation. Despite their importance, conventional platelet transfusions face several challenges. Platelets are stored at 20–24°C with continuous agitation, a requirement that limits shelf life and increases the risk of bacterial growth.1 Transfusion is also associated with complications including alloimmunisation, transfusion reactions, and transfusion-transmitted infection.1
These limitations have driven interest in alternative platelet products that offer improved stability and accessibility.
Lyophilised platelets: Technology and development
Lyophilisation removes water from platelet preparations through freezing and sublimation, producing a stable dry product that can be stored for prolonged periods before reconstitution.2
Several approaches to lyophilised platelet production are currently being investigated. These include the use of lyoprotectants to preserve platelet structure and functionality during freeze-drying, as well as sterilisation and pathogen-reduction technologies to enhance product safety.2,4 In parallel, researchers are developing modified and synthetic platelet-like particles designed to reproduce the key haemostatic functions of native platelets.5,6
Early lyophilised platelet formulations demonstrated reduced functionality compared with fresh platelets.3 However, advances in stabilisation methods have improved preservation of important biological characteristics, including surface receptor expression, adhesion to damaged vascular surfaces, and procoagulant activity.2,4
Clinical applications and potential benefits
The principal advantage of lyophilised platelets is their extended shelf life. Depending on formulation and storage conditions, these products may remain stable for months or even years at ambient temperatures.1,2 This eliminates the need for continuous cold-chain logistics and specialised storage facilities.
Lyophilised platelets may be particularly valuable in settings where conventional platelet products are difficult to access, including pre-hospital care, disaster response, and remote healthcare environments.1,2 Their improved stability also reduces product wastage and may enhance inventory efficiency.
Additional potential benefits include a lower risk of bacterial proliferation during storage and the integration of pathogen-reduction strategies during manufacturing.4 Preclinical studies, together with limited clinical experience, suggest that lyophilised platelet products can support clot formation and reduce bleeding in experimental trauma and haemorrhage models.1,3 At present, however, they are best considered an adjunct to conventional platelet transfusion rather than a direct replacement (Figure 1).
Figure 1. Comparison of conventional platelet concentrates and lyophilised platelet products, highlighting differences in shelf life, storage requirements, availability, preparation, safety, and haemostatic function.
Challenges and limitations
Despite their promise, several barriers must be overcome before lyophilised platelets can be widely implemented in clinical practice.
A major challenge is functional efficacy. Although modern products retain many platelet characteristics, aggregation responses and overall performance may still be reduced compared with fresh platelets.2,3 Questions therefore remain regarding their effectiveness in routine transfusion settings.
Manufacturing standardisation is another significant hurdle. Current production methods vary between organisations, and there is a lack of harmonised protocols. Regulatory pathways for these novel products are also still evolving. Safety remains an important consideration. Fixation, stabilisation, and pathogen-reduction processes may alter platelet surface characteristics, potentially affecting immunogenicity, circulation time, and biological behaviour.1,2,4 Further investigation is required to understand in vivo survival, clearance kinetics, and any impact on thrombosis risk.
Finally, production costs and scalability may influence adoption, particularly if manufacturing remains more complex than that of conventional platelet products.
Future directions
Research is increasingly focused on improving both the functionality and clinical utility of lyophilised platelets.2,4 Advances in stabilisation technologies aim to preserve platelet structure and receptor activity more effectively during freeze-drying. At the same time, synthetic and biomimetic platelet-like particles are being developed to reproduce specific haemostatic functions such as fibrin binding, clot contraction, and wound-healing support.5,6 Combination approaches incorporating lyophilised platelets alongside plasma or coagulation factors are also being explored to optimise haemostatic support in complex bleeding scenarios. Expanded translational and clinical studies will be essential to establish efficacy across trauma, surgery, and bleeding disorders.1,2
There is particular interest in the role of lyophilised platelet products in combat casualty care, trauma resuscitation, and resource-limited healthcare settings, where conventional platelets are often unavailable.1,2
Conclusions
Lyophilised platelets represent an important innovation in transfusion medicine with the potential to address many limitations associated with conventional platelet products. Their extended shelf life, ambient storage capability, and rapid availability make them especially attractive for hospital-based transfusion support, pre-hospital emergency care, and remote healthcare applications.
Although current products do not yet fully replicate the performance of fresh platelets, ongoing advances in formulation, standardisation, and clinical evaluation continue to improve their potential. As research progresses, lyophilised platelets may become a valuable component of future haemostatic and transfusion strategies.
References
1. Kogler VJ, Stolla M. There and back again: the once and current developments in donor-derived platelet products for hemostatic therapy. Blood. 2022. 2. He Y, Liu Y, Qi Y, Zheng S, Liu L. Preparation and application of freeze-dried platelets. Blood Genomics. 2022. 3. Read MS, Reddick RL, Bode AP, Bellinger DA, Nichols TC, Taylor K, et al. Preservation of hemostatic and structural properties of rehydrated lyophilized platelets: potential for long-term storage of dried platelets for transfusion. Proc Natl Acad Sci U S A. 1995. 4. Takhviji V, Jamali M, Deyhim MR, Sharifi Z. Enhancing platelet preservation through freeze-drying and sterilization: an approach for the improvement of hemostatic treatment and platelet concentrate supply. Iran J Pediatr Hematol Oncol. 2025. 5. Brown AC, Stabenfeldt SE, Ahn B, Hannan RT, Dhada KS, Herman ES, et al. Ultrasoft microgels displaying emergent, platelet-like behaviors. Nature Materials. 2014. 6. Nandi S, Sproul EP, Nellenbach K, Erb M, Gaffney L, Freytes DO, et al. Platelet-like particles dynamically stiffen fibrin matrices and improve wound healing outcomes. Biomaterials Science. 2019.
