A multicentred study to validate a consensus bleeding assessment tool developed by the biomedical excellence for safer transfusion collaborative for use in patients with haematological malignancy

Tranexamic acid versus placebo to prevent bleeding in patients with haematological malignancies and severe thrombocytopenia (TREATT): a randomised, double-blind, parallel, phase 3 superiority trial

BACKGROUND

Bleeding is common in patients with haematological malignancies undergoing intensive therapy. We aimed to assess the effect of tranexamic acid on preventing bleeding and the need for platelet transfusions.

METHODS

TREATT was an international, randomised, double-blind, parallel, phase 3 superiority trial conducted at 27 haematology centres in Australia and the UK. We enrolled adults (aged ≥18 years) receiving intensive chemotherapy or haematopoietic stem-cell transplantation for a haematological malignancy, with a platelet count of 10 × 109 platelets per L or less for 5 days or longer. Patients were randomly assigned (1:1) using block randomisation, stratified by site, to tranexamic acid (1 g every 8 h intravenously or 1·5g every 8 h orally) or placebo when their platelet count was less than 30 × 109 platelets per L. Treatment was continued until platelet recovery or day 30. Prophylactic platelet transfusions were maintained as standard of care. The primary endpoint was the proportion of patients who died or had WHO grade 2 or higher bleeding up to day 30. A modified intention-to-treat population including randomly assigned patients whose platelet count decreased to 30 × 109 platelets per L or less was used for analysis. This trial is registered with ClinicalTrials.gov (NCT03136445), ISRCTN (ISRCTN73545489), and the European Clinical Trials Register (EudraCT 2014-001513-35).

FINDINGS

Between June 23, 2015, and Feb 17, 2022, 1736 patients were screened for eligibility, 616 of whom were enrolled and randomly assigned (310 to tranexamic acid and 306 to placebo). 19 participants were excluded from the modified intention-to-treat analysis, leaving 300 participants in the tranexamic acid group and 297 in the placebo group. Participant median age was 58 years (IQR 49-65), 380 (62%) of 616 participants were male, and 235 (38%) were female. The proportion of participants who died or had WHO grade 2 or higher bleeding was 31·7% (90/298 [95% CI 26·6-37·4]) in the tranexamic acid group and 34·2% (98/295 [29·0-40·0]) in the placebo group (hazard ratio 0·92 [95% CI 0·67-1·27]; p=0·62). There were no differences in thrombotic events or veno-occlusive disease. 94 serious adverse events in 77 participants were reported up to day 60 in the tranexamic acid group and 103 events in 82 participants in the placebo group.

INTERPRETATION

There is insufficient evidence to support routine use of tranexamic acid to reduce bleeding in patients with haematological malignancies undergoing intensive chemotherapy.

FUNDING

UK National Health Service Blood and Transplant and Australian National Health and Medical Research Council.

Healthcare provider's perceptions of bleeding in patients with acute leukaemia undergoing induction chemotherapy: A qualitative study

BACKGROUND

Bleeding is a primary outcome for many transfusion-related trials in acute leukaemia (AL) patients, typically graded using the World Health Organisation (WHO) bleeding scale (clinically significant bleed (CSB) is ≥grade 2). This composite outcome fails to differentiate minor bleeds that may not be significant, poorly represents the total burden of bleeding and lacks input from healthcare providers (HCPs) and patients. As part of a multi-step project to create a better bleeding tool for trials, our objective was to identify HCPs' perspectives on the components of CSB in AL patients.

STUDY DESIGN AND METHODS

Using qualitative description, we interviewed 19 physicians and nurses who care for AL patients undergoing induction chemotherapy. Participants were recruited from professional organisations, networks and social media. An inductive approach to conventional content analysis was used.

RESULTS

HCPs identified features of CSB as the anatomical site of bleeding, amount of bleeding, need for intervention and changes in vital signs. Using these characteristics, bleeding events were categorised into three groups: clinically significant, could evolve into a CSB and not clinically significant. HCPs considered the patient's condition, bleeding history and clinical intuitions when deciding whether a bleed could escalate into serious bleeding.

DISCUSSION

Using data from HCPs, we categorised bleeds as clinically significant, could evolve into a CSB, and not significant. A study of patients' perspectives on the importance of different kinds of bleeding is the next step to creating a bleeding definition that is informed by evidence, clinicians and patients.

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

BACKGROUND

The short shelf-life of liquid-stored platelets (LP) at 20-24°C poses shortage and wastage challenges. Cryopreserved platelets have significantly extended shelf-life, and were safe and efficacious for therapeutic transfusions of bleeding patients in the Afghanistan conflict and phase 2 randomized studies. Although hematology patients account for half of platelets demand, there is no randomized study on prophylactic cryopreserved platelet transfusions in them.

METHODS

We performed a phase 1b/2a randomized cross-over study comparing the safety and efficacy of cryopreserved buffy coat-derived pooled platelets (CP) to LP in the prophylactic transfusions of thrombocytopenic hematology patients.

RESULTS

A total of 18 adults were randomly assigned 1:1 to CP and LP for their first thrombocytopenic period (TP) of up to 28-days. A total of 14 crossed over to the other platelet-arm for the second TP. Overall, 17 subjects received 51 CP and 15 received 52 LP. CP-arm had more treatment emergent adverse event (29.4% vs. 13.3% of subjects, 9.8% vs. 3.8% of transfusions) than LP-arm but all were mild. No thromboembolism was observed. Both arms had similar bleeding rates (23.5% vs. 26.7% of subjects) which were all mild. Subjects in CP-arm had lower average corrected count increments than LP-arm (mean [SD] 5.6 [4.20] vs. 22.6 [9.68] ×109 /L at 1-4 h, p < .001; 5.3 [4.84] vs. 18.2 [9.52] ×109 /L at 18-30 h, p < .001). All TEG parameters at 1-4 h and maximum amplitude (MA) at 18-30 h improved from baseline post-CP transfusion (p < .05) though improvements in K-time and MA were lower than LP (p < .05).

DISCUSSION

During shortages, CP may supplement LP in prophylactic transfusions of thrombocytopenic patients.

Recommended primary outcomes for clinical trials evaluating hemostatic blood products and agents in patients with bleeding: Proceedings of a National Heart Lung and Blood Institute and US Department of Defense Consensus Conference

ABSTRACT

High-quality evidence guiding optimal transfusion and other supportive therapies to reduce bleeding is needed to improve outcomes for patients with either severe bleeding or hemostatic disorders that are associated with poor outcomes. Alongside challenges in performing high-quality clinical trials in patient populations who are at risk of bleeding or who are actively bleeding, the interpretation of research evaluating hemostatic agents has been limited by inconsistency in the choice of primary trial outcomes. This lack of standardization of primary endpoints or outcomes decreases the ability of clinicians to assess the validity of endpoints and compare research results across studies, impairs meta-analytic efforts, and, ultimately, delays the translation of research results into clinical practice. To address this challenge, an international panel of experts was convened by the National Heart Lung and Blood Institute and the US Department of Defense on September 23 and 24, 2019, to develop expert opinion, consensus-based recommendations for primary clinical trial outcomes for pivotal trials in pediatric and adult patients with six categories in various clinical settings. This publication documents the conference proceedings from the workshop funded by the National Heart Lung and Blood Institute and the US Department of Defense that consolidated expert opinion regarding clinically meaningful outcomes across a wide range of disciplines to provide guidance for outcomes of future trials of hemostatic products and agents for patients with active bleeding.

Definition of a critical bleed in patients with immune thrombocytopenia: Communication from the ISTH SSC Subcommittee on Platelet Immunology

BACKGROUND

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts and increased risk of bleeding. In preparation for an upcoming guideline, the ITP Emergency Management Guideline Panel, including clinical experts in hematology, emergency medicine, research methodology, and patient representatives, identified the need for a standardized definition of a critical ITP bleed. The goal of the definition was to distinguish critical bleeds from bleeds that may not require urgent treatment, typically in the context of severe thrombocytopenia.

METHODS

The panel met in person and virtually to achieve consensus on the criteria for critical bleeding events among patients with ITP. Existing ITP bleeding scores and published definitions of major bleeds in patients receiving anticoagulation informed the definition of a critical ITP bleed. The Platelet Immunology Scientific Standardization Committee (SSC) of the International Society on Thrombosis and Haemostasis endorsed the definition.

RESULTS

A critical ITP bleed was defined as: (a) a bleed in a critical anatomical site including intracranial, intraspinal, intraocular, retroperitoneal, pericardial, or intramuscular with compartment syndrome; or (2) an ongoing bleed that results in hemodynamic instability or respiratory compromise.

CONCLUSION

The definition of a critical ITP bleed was developed by the ITP Emergency Management Guideline Panel and endorsed by the Platelet Immunology SSC. It incorporates both anatomic and physiologic risk and pertains to patients with confirmed or suspected ITP who typically have severe thrombocytopenia (platelet count below 20 × 109 /L).

The TREATT Trial (TRial to EvaluAte Tranexamic acid therapy in Thrombocytopenia): safety and efficacy of tranexamic acid in patients with haematological malignancies with severe thrombocytopenia: study protocol for a double-blind randomised controlled trial

Background

Patients with haematological malignancies often develop thrombocytopenia as a consequence of either their disease or its treatment. Platelet transfusions are commonly given to raise a low platelet count and reduce the risk of clinical bleeding (prophylaxis) or stop active bleeding (therapy). Recent studies have shown that many patients continue to experience bleeding despite the use of prophylactic platelet transfusions. Tranexamic acid is an anti-fibrinolytic, which reduces the breakdown of clots formed in response to bleeding. Anti-fibrinolytics have been shown to prevent bleeding, decrease blood loss and use of red cell transfusions in elective and emergency surgery, and are used widely in these settings. The aim of this trial is to test whether giving tranexamic acid to patients receiving treatment for haematological malignancies reduces the risk of bleeding or death and the need for platelet transfusions.

Methods

This is a multinational randomised, double-blind, placebo-controlled, parallel, superiority trial. Patients will be randomly assigned to receive tranexamic acid (given intravenously or orally) or a matching placebo in a 1:1 ratio, stratified by site. Patients with haematological malignancies receiving intensive chemotherapy or stem cell transplantation (or both) who are at least 18 years of age and expected to become severely thrombocytopenic for at least 5 days will be eligible for this trial. The primary outcome of the trial is the proportion of patients who died or had bleeding of World Health Organization grade 2 or above during the first 30 days of the trial. We will measure the rates of bleeding daily by using a short, structured assessment of bleeding, and we will record the number of transfusions given to patients. We will assess the risk of arterial and venous thrombosis for 120 days from the start of trial treatment.

Discussion

This trial will assess the safety and efficacy of using prophylactic tranexamic acid during a period of intensive chemotherapy and associated thrombocytopenia in people with haematological disorders.

Trial registration

This study was prospectively registered on Current Controlled Trials on 25 March 2015 (ISRCTN73545489) and is also registered on ClinicalTrials.gov (NCT03136445).

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3663-2) contains supplementary material, which is available to authorized users.