Buffy coat-derived platelets cryopreserved using a new method: Results from a pivotal clinical trial on thrombocytopenic patients with acute leukaemia

Abstract

The administration of cryopreserved platelets (PLTs) may overcome the limits of platelet shortage and availability, especially during some seasons or in specific contexts like rural areas. After in vitro validation studies, ad hoc prepared buffy coat-derived pooled platelet concentrates (BC-PLTs), treated with dimethyl sulphoxide (DMSO) and cryopreserved (CRY BC-PLTs) at-80°C with a modified Valeri method, were transfused in patients with severe thrombocytopenia secondary to chemotherapy for acute leukaemia (AL). Five inpatients were enrolled in the pivotal clinical trial NCT02032134: 4 males and 1 female with a mean age of 71 years (range: 65-80). Four patients were diagnosed with acute myeloid leukaemia and 1 had acute lymphoblastic leukaemia.Transfusion of one Unit of CRY BC-PLTs resulted effective in active bleeding control in two patients without any adverse reaction or concomitant antihaemorrhagic therapies. CRY BC-PLTs met the currently accepted criteria for cryopreserved PLTs, their transfusion in patients with AL was safe. (Clinical trial: NCT02032134).

A randomized cross‐over study of cryopreserved platelets in prophylactic transfusions of thrombocytopenic patients

“…8,[15][16][17][18] The most recent published study was also non-randomized and enrolled only five patients because of recruitment difficulties. 11 Major breakthrough bleeding during prophylactic transfusions with cryopreserved platelets is a safety concern as they have substantially reduced in vivo recoveries. Another concern which needs more evaluation is the potential thromboembolic risks of cryopreserved platelets because of their procoagulant phenotype, especially with repeated transfusions in the non-bleeding patients.…”

“…They generally involved shorter observational period and focused on surrogate outcome measures such as CCI or bleeding time rather than bleeding 8,15–18 . The most recent published study was also non‐randomized and enrolled only five patients because of recruitment difficulties 11 …”

“…8,10 Only a few involved allogeneic platelets. 8,11 There is also a lack of prospective randomized studies comparing the safety and efficacy of cryopreserved to liquid-stored allogeneic platelets in this setting.…”

“…Published reports on the safety and efficacy of prophylactic cryopreserved platelets transfusions of thrombocytopenic patients mostly involved autologous platelets in HLA‐alloimmunized platelet refractory hematology patients 8,10 . Only a few involved allogeneic platelets 8,11 . There is also a lack of prospective randomized studies comparing the safety and efficacy of cryopreserved to liquid‐stored allogeneic platelets in this setting.…”

Novel blood derived hemostatic agents for bleeding therapy and prophylaxis

“…Already in the 21st century, noncontrolled, observational studies of CPP in bleeding patients have been reported, but they come with limited ability to define outcome superiority or inferiority [99]. A dose escalation trial of CPP compared to standard liquid stored platelet products was performed in bleeding patients with thrombocytopenia [100].…”