Abstract

BACKGROUND Equitable allocation of scarce blood products needed for a randomized controlled trial (RCT) is a complex decision-making process within the blood supply chain. Strategies to improve resource allocation in this setting are lacking. METHODS We designed a custom-made, computerized system to manage the inventory and allocation of COVID-19 convalescent plasma (CCP) in a multi-site RCT, CONCOR-1. A hub-and-spoke distribution model enabled real-time inventory monitoring and assignment for randomization. A live CCP inventory system using REDCap was programmed for spoke sites to reserve, assign, and order CCP from hospital hubs. A data-driven mixed-integer programming model with supply and demand forecasting was developed to guide the equitable allocation of CCP at hubs across Canada (excluding Québec). RESULTS 18/38 hospital study sites were hubs with a median of 2 spoke sites per hub. A total of 394.5 500-ml doses of CCP were distributed; 349.5 (88.6%) doses were transfused; 9.5 (2.4%) were wasted due to mechanical damage sustained to the blood bags; 35.5 (9.0%) were unused at the end of the trial. Due to supply shortages, 53/394.5 (13.4%) doses were imported from Héma-Québec to Canadian Blood Services (CBS), and 125 (31.7%) were transferred between CBS regional distribution centers to meet demand. 137/349.5 (39.2%) and 212.5 (60.8%) doses were transfused at hubs and spoke sites, respectively. The mean percentages of total unmet demand were similar across the hubs, indicating equitable allocation, using our model. CONCLUSION Computerized tools can provide efficient and immediate solutions for equitable allocation decisions of scarce blood products in RCTs.

Abstract

IMPORTANCE The evidence for benefit of convalescent plasma for critically ill patients with COVID-19 is inconclusive. OBJECTIVE To determine whether convalescent plasma would improve outcomes for critically ill adults with COVID-19. DESIGN, SETTING, AND PARTICIPANTS The ongoing Randomized, Embedded, Multifactorial, Adaptive Platform Trial for Community-Acquired Pneumonia (REMAP-CAP) enrolled and randomized 4763 adults with suspected or confirmed COVID-19 between March 9, 2020, and January 18, 2021, within at least 1 domain; 2011 critically ill adults were randomized to open-label interventions in the immunoglobulin domain at 129 sites in 4 countries. Follow-up ended on April 19, 2021. INTERVENTIONS The immunoglobulin domain randomized participants to receive 2 units of high-titer, ABO-compatible convalescent plasma (total volume of 550 mL ± 150 mL) within 48 hours of randomization (n = 1084) or no convalescent plasma (n = 916). MAIN OUTCOMES AND MEASURES The primary ordinal end point was organ support-free days (days alive and free of intensive care unit-based organ support) up to day 21 (range, -1 to 21 days; patients who died were assigned -1 day). The primary analysis was an adjusted bayesian cumulative logistic model. Superiority was defined as the posterior probability of an odds ratio (OR) greater than 1 (threshold for trial conclusion of superiority >99%). Futility was defined as the posterior probability of an OR less than 1.2 (threshold for trial conclusion of futility >95%). An OR greater than 1 represented improved survival, more organ support-free days, or both. The prespecified secondary outcomes included in-hospital survival; 28-day survival; 90-day survival; respiratory support-free days; cardiovascular support-free days; progression to invasive mechanical ventilation, extracorporeal mechanical oxygenation, or death; intensive care unit length of stay; hospital length of stay; World Health Organization ordinal scale score at day 14; venous thromboembolic events at 90 days; and serious adverse events. RESULTS Among the 2011 participants who were randomized (median age, 61 [IQR, 52 to 70] years and 645/1998 [32.3%] women), 1990 (99%) completed the trial. The convalescent plasma intervention was stopped after the prespecified criterion for futility was met. The median number of organ support-free days was 0 (IQR, -1 to 16) in the convalescent plasma group and 3 (IQR, -1 to 16) in the no convalescent plasma group. The in-hospital mortality rate was 37.3% (401/1075) for the convalescent plasma group and 38.4% (347/904) for the no convalescent plasma group and the median number of days alive and free of organ support was 14 (IQR, 3 to 18) and 14 (IQR, 7 to 18), respectively. The median-adjusted OR was 0.97 (95% credible interval, 0.83 to 1.15) and the posterior probability of futility (OR <1.2) was 99.4% for the convalescent plasma group compared with the no convalescent plasma group. The treatment effects were consistent across the primary outcome and the 11 secondary outcomes. Serious adverse events were reported in 3.0% (32/1075) of participants in the convalescent plasma group and in 1.3% (12/905) of participants in the no convalescent plasma group. CONCLUSIONS AND RELEVANCE Among critically ill adults with confirmed COVID-19, treatment with 2 units of high-titer, ABO-compatible convalescent plasma had a low likelihood of providing improvement in the number of organ support-free days. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT02735707.

Abstract

The efficacy of convalescent plasma for coronavirus disease 2019 (COVID-19) is unclear. Although most randomized controlled trials have shown negative results, uncontrolled studies have suggested that the antibody content could influence patient outcomes. We conducted an open-label, randomized controlled trial of convalescent plasma for adults with COVID-19 receiving oxygen within 12 d of respiratory symptom onset ( NCT04348656 ). Patients were allocated 2:1 to 500 ml of convalescent plasma or standard of care. The composite primary outcome was intubation or death by 30 d. Exploratory analyses of the effect of convalescent plasma antibodies on the primary outcome was assessed by logistic regression. The trial was terminated at 78% of planned enrollment after meeting stopping criteria for futility. In total, 940 patients were randomized, and 921 patients were included in the intention-to-treat analysis. Intubation or death occurred in 199/614 (32.4%) patients in the convalescent plasma arm and 86/307 (28.0%) patients in the standard of care arm-relative risk (RR) = 1.16 (95% confidence interval (CI) 0.94-1.43, P = 0.18). Patients in the convalescent plasma arm had more serious adverse events (33.4% versus 26.4%; RR = 1.27, 95% CI 1.02-1.57, P = 0.034). The antibody content significantly modulated the therapeutic effect of convalescent plasma. In multivariate analysis, each standardized log increase in neutralization or antibody-dependent cellular cytotoxicity independently reduced the potential harmful effect of plasma (odds ratio (OR) = 0.74, 95% CI 0.57-0.95 and OR = 0.66, 95% CI 0.50-0.87, respectively), whereas IgG against the full transmembrane spike protein increased it (OR = 1.53, 95% CI 1.14-2.05). Convalescent plasma did not reduce the risk of intubation or death at 30 d in hospitalized patients with COVID-19. Transfusion of convalescent plasma with unfavorable antibody profiles could be associated with worse clinical outcomes compared to standard care.

Abstract

Clinically significant bleeding in patients with hematologic malignancies is a heterogeneous composite outcome currently defined as World Health Organization (WHO) bleeding Grades 2, 3, and 4. However, the clinical significance of some minor bleeds categorized as WHO Grades 1 and 2 remains controversial. We analyzed the number and frequency of individual signs and symptoms of WHO Grades 1 and 2 bleeds and explored their association with more severe incident bleeds graded as WHO Grades 3 and 4. STUDY DESIGN AND METHODS We aggregated daily bleeding assessment data from three randomized controlled trials conducted in patients with hematologic malignancies that used bleeding as an outcome. Cox proportional hazard regression analysis was used to identify signs and symptoms categorized as WHO Grades 1 and 2 bleeds that were associated with more severe bleeds (Grades 3 and 4). RESULTS We collected data from 315 patients (n = 5476 daily bleeding assessments; 3383 [61.8%] with a bleed documented). A total of 98.3% (3326/3383) were Grade 1 and 2 bleeds and 1.7% (57/3383) were Grades 3 and 4. Grade 1 and 2 bleeds were composed of 20 different bleeding signs and symptoms. Hematuria (hazard ratio, 16.1; 95% confidence interval, 4.4-59.2; P < .0001) was associated with incident Grade 3 or 4 bleeds. CONCLUSION In patients with hematologic malignancy, only hematuria (microscopic and/or macroscopic) was associated with more severe incident bleeds. This findings require validation in independent data sets.

Abstract

BACKGROUND Patients with immune thrombocytopenia are at risk of bleeding during surgery, and intravenous immunoglobulin is commonly used to increase the platelet count. We aimed to establish whether perioperative eltrombopag was non-inferior to intravenous immunoglobulin. METHODS We did a randomised, open-label trial in eight academic hospitals in Canada. Patients were aged at least 18 years, with primary or secondary immune thrombocytopenia and platelet counts less than 100 × 10(9) cells per L before major surgery or less than 50 × 10(9) cells per L before minor surgery. Previous intravenous immunoglobulin within 2 weeks or thrombopoietin receptor agonists within 4 weeks before randomisation were not permitted. Patients were randomly assigned to receive oral daily eltrombopag 50 mg from 21 days preoperatively to postoperative day 7 or intravenous immunoglobulin 1 g/kg or 2 g/kg 7 days before surgery. Eltrombopag dose adjustments were allowed weekly based on platelet counts. The randomisation sequence was generated by a computerised random number generator, concealed and stratified by centre and surgery type (major or minor). The central study statistician was masked to treatment allocation. The primary outcome was achievement of perioperative platelet count targets (90 × 10(9) cells per L before major surgery or 45 × 10(9) cells per L before minor surgery) without rescue treatment. We did intention-to-treat and per-protocol analyses using an absolute non-inferiority margin of -10%. This trial is registered with ClinicalTrials.gov, NCT01621204. FINDINGS Between June 5, 2013, and March 7, 2019, 92 patients with immune thrombocytopenia were screened, of whom 74 (80%) were randomly assigned: 38 to eltrombopag and 36 to intravenous immunoglobulin. Median follow-up was 50 days (IQR 49-55). By intention-to-treat analysis, perioperative platelet targets were achieved for 30 (79%) of 38 patients assigned to eltrombopag and 22 (61%) of 36 patients assigned to intravenous immunoglobulin (absolute risk difference 17·8%, one-sided lower limit of the 95% CI 0·4%; p(non-inferiority)=0·005). In the per-protocol analysis, perioperative platelet targets were achieved for 29 (78%) of 37 patients in the eltrombopag group and 20 (63%) of 32 in the intravenous immunoglobulin group (absolute risk difference 15·9%, one-sided lower limit of the 95% CI -2·1%; p(non-inferiority)=0·009). Two serious adverse events occurred in the eltrombopag group: one treatment-related pulmonary embolism and one vertigo. Five serious adverse events occurred in the intravenous immunoglobulin group (atrial fibrillation, pancreatitis, vulvar pain, chest tube malfunction and conversion to open splenectomy); all were related to complications of surgery. No treatment-related deaths occurred. INTERPRETATION Eltrombopag is an effective alternative to intravenous immunoglobulin for perioperative treatment of immune thrombocytopenia. However, treatment with eltrombopag might increase risk of thrombosis. The decision to choose one treatment over the other will depend on patient preference, resource limitations, cost, and individual risk profiles. FUNDING GlaxoSmithKline and Novartis.

Abstract

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) may result in severe bleeding, particularly fetal and neonatal intracranial haemorrhage (ICH). As a result, FNAIT requires prompt identification and treatment; subsequent pregnancies need close surveillance and management. An international panel convened to develop evidence-based recommendations for diagnosis and management of FNAIT. A rigorous approach was used to search, review and develop recommendations from published data for: antenatal management, postnatal management, diagnostic testing and universal screening. To confirm FNAIT, fetal human platelet antigen (HPA) typing, using non-invasive methods if quality-assured, should be performed during pregnancy when the father is unknown, unavailable for testing or heterozygous for the implicated antigen. Women with a previous child with an ICH related to FNAIT should be offered intravenous immunoglobulin (IVIG) infusions during subsequent affected pregnancies as early as 12 weeks gestation. Ideally, HPA-selected platelets should be available at delivery for potentially affected infants and used to increase the neonatal platelet count as needed. If HPA-selected platelets are not immediately available, unselected platelets should be transfused. FNAIT studies that optimize antenatal and postnatal management, develop risk stratification algorithms to guide management and standardize laboratory testing to identify high risk pregnancies are needed.

Abstract

Two randomized, double-blind, placebo-controlled studies demonstrated responses (≥50,000/muL) to fostamatinib in adults with long-standing immune thrombocytopenia (ITP). The long-term safety and efficacy of fostamatinib was evaluated in a follow-on, open-label-extension (OLE) study. Patients received double-blind fostamatinib in the randomized trials, and responders continued the same dose, 100-150mg BID, in the OLE. Non-responders received 100mg bid for 4 weeks and could escalate to 150mg bid at Week 4. Endpoints included stable response, platelet count ≥50,000/muL at 4/6 biweekly (randomized trials) or 2/3 monthly visits (OLE), and overall response, ≥1 platelet count ≥50,000/muL during Weeks 1-12. 146 patients received fostamatinib including 123 in the OLE. Median treatment duration was 6.7 months. Baseline median ITP duration was 8 years and median platelet count 16,000/muL; prior treatments included thrombopoietic agents (47%), splenectomy (35%), and rituximab (32%). Twenty-seven (18%) patients achieved a stable response, median duration >28 months, and median platelet count 89,000/muL. Sixty-four (44%) patients achieved an overall response (including stable responders) with median platelet count 63,000/muL and median response duration >28 months. 24/71 (34%) patients who had failed a thrombopoeitic agent achieved overall responses to fostamatinib. The most common AEs were diarrhea, hypertension, nausea, epistaxis and abnormal LFTs. Most AEs were mild/moderate and resolved or were managed with dose reduction, dose interruption, and/or secondary medication. Almost half of patients achieved an overall response, and most of these maintained their responses for >2 years. No new or increased frequency of AEs were seen at up to 31 months of treatment. This article is protected by copyright. All rights reserved.

Abstract

OBJECTIVE Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is associated with life-threatening bleeding. This systematic review of postnatal management of FNAIT examined transfusion of human platelet antigen (HPA) selected or unselected platelets, and/or IVIg on platelet increments, hemorrhage and mortality. STUDY DESIGN MEDLINE, EMBASE and Cochrane searches were conducted until 11 May 2018. RESULT Of 754 neonates, 382 received platelet transfusions (51%). HPA-selected platelets resulted in higher platelet increments and longer response times than HPA-unselected platelets. However, unselected platelets generally led to sufficient platelet increments to 30 x 10(9)/L, a level above which intracranial hemorrhage or other life-threatening bleeding rarely occurred. Platelet increments were not improved with the addition of IVIg to platelet transfusion. CONCLUSION Overall, HPA-selected platelet transfusions were more effective than HPA-unselected platelets but unselected platelets were often effective enough to achieve clinical goals. Available studies do not clearly demonstrate a benefit for addition of IVIg to platelet transfusion.

Abstract

BACKGROUND The Bridging ITP Trial is an open-label randomized trial designed to compare the oral thrombopoietin receptor agonist eltrombopag and intravenous immune globulin (IVIG) for patients with immune thrombocytopaenia (ITP) who require an increase in platelet count before elective surgery. Here, we report the study methods and rationale. METHODS We designed a multi-centre, non-inferiority randomized trial comparing daily oral eltrombopag starting 3 weeks pre-operatively, and IVIG administered 1 week pre-operatively for patients with ITP requiring a platelet count increase prior to surgery. Starting dose of eltrombopag is 50 mg daily with a weekly pre-operative dose titration schedule, and treatment is continued for 1 week after surgical haemostasis is achieved. IVIG is administered at a dose of 1 to 2 g/kg 1 week pre-operatively with the allowance for a second dose within 1 week after surgical haemostasis. The objective of the study is to demonstrate non-inferiority of eltrombopag for the primary endpoint of achieving the pre-operative platelet count threshold (50 x 10(9)/L for minor surgery; or 100 x 10(9)/L for major surgery) and sustaining platelet count levels above the threshold for 1 week after surgical haemostasis is achieved, without the use of rescue treatment. Secondary endpoints include thrombosis, bleeding and patient satisfaction. CONCLUSION The Bridging ITP Trial will evaluate the efficacy and safety of eltrombopag as an alternative to IVIG in the peri-operative setting for patients with ITP. The protocol was designed to provide a management strategy that can be applied in clinical practice. CLINICALTRIALS. GOV IDENTIFIER NCT01621204.

Abstract

BACKGROUND AND OBJECTIVES Selection of a compatible red blood cell (RBC) unit does not include matching for donor sex. This systematic review and meta-analysis aims to summarize the evidence examining the impact of sex-mismatched RBC transfusion on recipient mortality. MATERIALS AND METHODS Ovid MEDLINE, Ovid EMBASE, CINAHL, PubMed, Web of Science and the Cochrane Database of Systematic Reviews were searched from inception up to 23 November 2018. Randomized controlled trials and observational studies were included in the search. Eligible studies reported on the impact of sex-matched compared to sex-mismatched RBC transfusion on recipient mortality. Two investigators independently extracted data and assessed study quality. A three-level meta-analytic model was applied to emphasize the unknown dependence among the effect sizes. RESULTS Five retrospective observational studies (n = 86 737) were included; no RCTs were found. Sex-mismatched RBC transfusions were associated with a higher risk of death compared with sex-matched transfusions (pooled hazard ratio [HR]: 1.13; 95% confidence interval [CI]: 1.02-1.24). In the subgroup of cardiovascular surgery (n = 57 712), there was no significant increase in mortality with sex-mismatched transfusions (pooled HR: 1.08; 95% CI: 0.95-1.22). The data were prone to confounding, selection bias and reporting bias. Certainty of the evidence was very low. CONCLUSION Sex-mismatched RBC transfusions were associated with an increased risk of death in this pooled analysis. However, the certainty of the evidence was very low from observational studies. The need to match donor and recipient sex for transfusions requires further investigation because of the potential widespread impact.