Platelet Transfusions in Hematopoietic Stem Cell Transplantation (The PATH III Trial)

In Canada, over 1,500 autologous hematopoietic stem cell transplantations (ASCT) are performed annually for hematologic malignancies. It is currently standard practice to provide a prophylactic transfusion of platelets to prevent bleeding when the daily measured platelet count is less than 10 x 109/L. A patient may require up to six adult platelet doses during the post-transplant period. However, the true benefit of prophylactic platelet transfusions in the ASCT setting is unclear and has been called into question by several recent studies.

Prophylactic platelet transfusions may not only be unnecessary, they may be detrimental to the patient. Among blood products, platelet transfusions are associated with the highest risk of both infectious and non-infectious complications: this would include bacterial infections and allergic /febrile reactions. Moreover, the potential overuse of platelet products places a significant burden on a scarce health care resource that is provided through volunteer donations.

An alternative strategy to prevent bleeding and reduce the need for platelet transfusions involves administering Tranexamic Acid, an antifibrinolytic agent to stabilize blood clots and reduce bleeding. Tranexamic Acid is safe and effective in many clinical scenarios, and may be a reasonable alternative for prophylactic platelet transfusions. In the setting of ASCT, Tranexamic Acid may reduce bleeding and further enhance a strategy of therapeutic platelet transfusions where platelets are administered only in the event of active bleeding symptoms.

The effect of prophylactic platelet transfusions and Tranexamic Acid on clinical, quality of life and economic outcomes in patients receiving ASCT is unknown. The primary aim of this research program is to perform a randomized controlled trial to determine whether a strategy of prophylactic Tranexamic Acid (with therapeutic platelet transfusions) is safe and effective compared to prophylactic platelet transfusions in patients undergoing ASCT.

A pilot trial demonstrated feasibility by successfully recruiting 100 patients and these patients will be rolled over into the phase III study. The treatment assignment and bleeding outcomes for these patients remain blinded.

• WHO bleeding events of Grade 3 or 4 [Срок оценки: Daily, up to 30 days]
• Time from randomization to bleeding of WHO events Grade 2 or higher [Срок оценки: Daily, up to 30 days]
• Number of days with bleeding of WHO bleeding events Grade 2 or higher [Срок оценки: Daily, up to 30 days]
• Bleeding Severity Measurement Scale (BSMS) for bleeding events Grade 2 or higher [Срок оценки: Daily, up to 30 days]
• Number of platelet and/or red blood cell transfusions [Срок оценки: Daily, up to 30 days]
• Adverse reactions related to tranexamic acid [Срок оценки: Daily, up to 30 days.]
• Venous thromboembolism grade 2 or higher [Срок оценки: Daily, up to 30 days.]
• Adverse reactions related to platelet transfusion [Срок оценки: Daily, up to 30 days.]
• Time to platelet count recovery [Срок оценки: Daily, up to 30 days.]
• Number of days with a platelet count < 10 x 109/L [Срок оценки: Daily, up to 30 days.]
• LOS (Length of hospital stay) [Срок оценки: LOS will be measured as the number of days elapsed between hospital admission and hospital discharge date up to 30 days.]
• Transplant related outcome: Bearman Scoring System for Organ Toxicity following HSCT [Срок оценки: Day 30]