Efficacy and Safety Analyses of Recombinant Factor VIIa in Severe Post-Partum Hemorrhage.

Background: Despite a range of available treatments, it is still sometimes challenging to treat patients with severe post-partum hemorrhage (sPPH). Objective: This study evaluated the efficacy and safety of recombinant activated factor VIIa (rFVIIa) in sPPH management. Methods: An open-label, multi-center, randomized controlled trial (RCT; NCT00370877) and four observational studies (OS; OS-1 (NCT04723979), OS-2, OS-3, and OS-4) were analyzed regarding efficacy (need for subsequent invasive procedures, including uterine compression sutures, uterine or iliac artery ligations, arterial embolization, or hysterectomy) and safety (incidence of thromboembolic events (TE) and maternal mortality) of rFVIIa for sPPH. The RCT, and OS-1 and OS-2, included a control group of women who did not receive rFVIIa (with propensity score-matching used in OS-1 and OS-2), whereas OS-3 and OS-4 provided descriptive data for rFVIIa-exposed women only. Results: A total of 446 women exposed to rFVIIa and 1717 non-exposed controls were included. In the RCT, fewer rFVIIa-exposed women (50% [21/42]) had an invasive procedure versus non-exposed women (91% [38/42]; odds ratio: 0.11; 95% confidence interval: 0.03-0.35). In OS-1, more rFVIIa-exposed women (58% [22/38]) had an invasive procedure versus non-exposed women (35% [13.3/38]; odds ratio: 2.46; 95% confidence interval: 1.06-5.99). In OS-2, 17% (3/18) of rFVIIa-exposed women and 32% (5.6/17.8) of non-exposed women had an invasive procedure (odds ratio: 0.33; 95% confidence interval: 0.03-1.75). Across all included women, TEs occurred in 1.5% (0.2% arterial and 1.2% venous) of rFVIIa-exposed women and 1.6% (0.2% arterial and 1.4% venous) of non-exposed women with available data. Conclusions: The positive treatment effect of rFVIIa on the RCT was not confirmed in the OS. However, the safety analysis did not show any increased incidence of TEs with rFVIIa treatment.

The establishment of a multiple myeloma clinical registry in the Asia-Pacific region: The Asia-Pacific Myeloma and Related Diseases Registry (APAC MRDR).

BACKGROUND: Multiple myeloma (MM) is the second most common haematological cancer worldwide. Along with related diseases including monoclonal gammopathy of undetermined significance (MGUS), plasma cell leukaemia (PCL) and plasmacytoma, MM incidence is rising, yet it remains incurable and represents a significant disease burden. Clinical registries can provide important information on management and outcomes, and are vital platforms for clinical trials and other research. The Asia-Pacific Myeloma and Related Diseases Registry (APAC MRDR) was developed to monitor and explore variation in epidemiology, treatment regimens and their impact on clinical outcomes across this region. Here we describe the registry's design and development, initial data, progress and future plans. METHODS: The APAC MRDR was established in 2018 as a multicentre collaboration across the Asia-Pacific, collecting prospective data on patients newly diagnosed with MM, MGUS, PCL and plasmacytoma in Korea, Singapore, Malaysia and Taiwan, with China recently joining. Development of the registry required a multidisciplinary team of clinicians, researchers, legal and information technology support, and financial resources, as well as local clinical context from key opinion leaders in the APAC region. Written informed consent is obtained and data are routinely collected throughout treatment by hospital staff. Data are stored securely, meeting all local privacy and ethics requirements. Data were collected from October 2018 to March 2024. RESULTS: Over 1700 patients from 24 hospitals have been enrolled onto the APAC MRDR to date, with the majority (86%) being newly diagnosed with MM. Bortezomib with an immunomodulatory drug was most frequently used in first-line MM therapy, and lenalidomide-based therapy was most common in second-line. Establishment and implementation challenges include regulatory and a range of operational issues. CONCLUSION: The APAC MRDR is providing 'real-world' data to participating sites, clinicians and policy-makers to explore factors influencing outcomes and survival, and to support high quality studies. It is already a valuable resource that will continue to grow and support research and clinical collaboration in MM and related diseases across the APAC region.

Immunoglobulin replacement vs prophylactic antibiotics for hypogammaglobulinemia secondary to hematological malignancy.

ABSTRACT: Immunoglobulin replacement and prophylactic antibiotics are commonly used to prevent infections in patients with secondary hypogammaglobulinemia due to hematological malignancies but have never been directly compared. In this randomized controlled feasibility trial conducted in 7 hospitals in Australia and New Zealand, we enrolled patients with secondary hypogammaglobulinemia with either a history of recurrent/severe infection or an immunoglobulin G level <4 g/L. Participants were randomized in a 1:2 ratio to immunoglobulin (0.4 g/kg per 4 weeks IV) or daily antibiotics (trimethoprim-sulfamethoxazole 160 mg/800 mg or, if contraindicated, 100 mg doxycycline) for 12 months. Participants allocated to antibiotics were allowed to crossover after grade ≥3 infections. The primary outcome was proportion of patients alive on the assigned treatment 12 months after randomization. Between August 2017 and April 2019, 63 patients were randomized: 42 to antibiotics and 21 to immunoglobulin. Proportion of participants alive on allocated treatment at 12 months was 76% in the immunoglobulin and 71% in the antibiotic arm (Fisher exact test P=.77; odds ratio, 0.78; 95% CI, 0.22-2.52). The lower quartile for time to first major infection (median, not reached) was 11.1 months for the immunoglobulin and 9.7 months for the antibiotic arm (log-rank test, P=.65). Three participants in the immunoglobulin and 2 in the antibiotic arm had grade ≥3 treatment-related adverse events. A similar proportion of participants remained on antibiotic prophylaxis at 12 months to those on immunoglobulin, with similar rates of major infections. Our findings support the feasibility of progressing to a phase 3 trial. Trial registration #ACTRN12616001723471.

Economic evaluation: immunoglobulin vs prophylactic antibiotics in hypogammaglobulinemia and hematological malignancies.

ABSTRACT: Patients with hematological malignancies are at high risk of developing hypogammaglobulinemia (HGG) and infections. Immunoglobulin (Ig) is one recommended option to prevent these infections, but it is expensive, and its cost-effectiveness compared with other prevention strategies remains unknown. We conducted a trial-based economic evaluation from the Australian health care system perspective to estimate the 12-month cost-effectiveness of prophylactic Ig vs prophylactic antibiotics in 63 adults with HGG and hematological malignancies participating in the RATIONAL feasibility trial. Two analyses were conducted: (1) cost-utility analysis to assess the incremental cost per quality-adjusted life year (QALY) gained; and (2) cost-effectiveness analysis to assess the incremental cost per serious infection prevented (grade ≥3) and per any infection (any grade) prevented. Over 12 months, the total cost per patient was significantly higher in the Ig group than in the antibiotic group (mean difference, AU$29 140; P < .001). Most patients received IVIg, which was the main cost driver; only 2 patients in the intervention arm received subcutaneous Ig. There were nonsignificant differences in health outcomes. Results showed Ig was more costly than antibiotics and associated with fewer QALYs. The incremental cost-effectiveness ratio of Ig vs antibiotics was AU$111 262 per serious infection prevented, but Ig was more costly and associated with more infections when all infections were included. On average and for this patient population, Ig prophylaxis may not be cost-effective compared with prophylactic antibiotics. Further research is needed to confirm these findings in a larger population and considering longer-term outcomes. The trial was registered at the Australian and New Zealand Clinical Trials Registry as #ACTRN12616001723471.

Impact and utility of follicular lymphoma GELF criteria in routine care: an Australasian Lymphoma Alliance study.

Follicular Lymphoma (FL) treatment initiation is largely determined by tumor burden and symptoms. In the pre-rituximab era, the Group d'Etude des Lymphomes Folliculaires (GELF) developed widely adopted criteria to identify high tumor burden FL patients to harmonize clinical trial populations. The utilization of GELF criteria (GELFc) in routine therapeutic decision-making is poorly described. This multicenter retrospective study evaluated patterns of GELFc at presentation and GELFc utilization in therapeutic decision-making in newly diagnosed, advanced stage rituximab-era FL. Associations between GELFc, treatment given, and patient survival were analyzed in 300 eligible cases identified between 2002-2019. 163 (54%) had ≥1 GELFc at diagnosis. The presence or cumulative number of GELFc did not predict PFS in patients undergoing watch-and-wait (WW) or those receiving systemic treatment. Of interest, in patients with ≥1 GELFc, 16/163 (10%) underwent initial watch-and-wait (comprising 22% of the watchand- wait cohort). In those receiving systemic therapy +/- radiotherapy, 74/215 (34%) met no GELFc. Our data suggest clinicians are using adjunctive measures to make decisions regarding treatment initiation in a significant proportion of patients. By restricting FL clinical trial eligibility only to those meeting GELFc, reported outcomes may not be applicable to a significant proportion of patients treated in routine care settings.

When to use tranexamic acid for the treatment of major bleeding?

Tranexamic acid (TXA) is an antifibrinolytic agent originally developed for the management of bleeding in the setting of postpartum hemorrhage (PPH). Over the last 15 years, there has been accumulating evidence on the use of TXA for the treatment of active bleeding in a variety of clinical contexts. Clinical trials have shown that the efficacy and safety of TXA for the treatment of bleeding differ according to the clinical context in which it is being administered, timing of administration, and dose. Early administration is important for efficacy, particularly in trauma and PPH. Further studies are needed to understand the mechanisms by which TXA provides benefit, optimal modes of administration and dosing, and its effect in some clinical settings, such as spontaneous intracerebral hemorrhage. There is no evidence that TXA increases the risk of thrombotic events in patients with major bleeding overall. However, there is evidence of increased risk of venous thrombosis in patients with gastrointestinal bleeding. There is also evidence of increased risk of seizures with the use of higher doses. This review summarizes the current evidence for the use of TXA for patients with active bleeding and highlights the importance of generating evidence of efficacy and safety of hemostatic interventions specific to the bleeding contexts-as findings from 1 clinical setting may not be generalizable to other contexts-and that of individual patient assessment for bleeding, thrombotic, and other risks, as well as important logistical and other practical considerations, to optimize care and outcomes in these settings.

Use of platelet transfusions and tranexamic acid in patients with myelodysplastic syndromes: A clinical practice survey.

AIM: Thrombocytopenia and bleeding are common in myelodysplastic syndromes (MDS), but optimal management is unknown. We conducted a survey to identify current clinical practice regarding platelet transfusion (PLT-T) and tranexamic acid (TXA) to inform future trial design. METHOD: A 25-question survey was distributed to members of the ALLG from December 2020 to July 2021. RESULTS: Sixty-four clinicians across Australia, New Zealand and Singapore responded. Clinicians treated a median of 15 MDS patients annually. Twenty-nine (45%) reported having institutional guidelines regarding prophylactic PLT-T. Although 60 (94%) said they would consider using TXA, most (58/64; 91%) did not have institutional guidelines. Clinical scenarios showed prophylactic PLT-T was more likely administered for patients on disease-modifying therapy (49/64; 76%, commonest threshold <10 × 109 /L) or with minor bleeding (32/64 [50%] transfusing at threshold <20 × 109 /L, 23/64 [35%] at <10 × 109 /L). For stable untreated patients, 29/64 (45%) would not give PLT-T and 32/64 (50%) would. Most respondents (46/64; 72%) were interested in participating in trials in this area. Potential barriers included resource limitations, funding and patient/clinician acceptance. CONCLUSION: Real-world management of MDS-related thrombocytopenia varies and there is a need for clinical trials to inform practice.

The Australian Aplastic Anaemia and other Bone Marrow Failure Syndromes Registry.

The bone marrow failure syndromes (BMFS) are a diverse group of acquired and inherited diseases which may manifest in cytopenias, haematological malignancy and/or syndromic multisystem disease. Patients with BMFS frequently experience poor outcomes, and improved treatment strategies are needed. Collation of clinical characteristics and patient outcomes in a national disease-specific registry represents a powerful tool to identify areas of need and support clinical and research collaboration. Novel treatment strategies such as gene therapy, particularly in rare diseases, will depend on the ability to identify eligible patients alongside the molecular genetic features of their disease that may be amenable to novel therapy. The Australian Aplastic Anaemia and other Bone Marrow Failure Syndromes Registry (AAR) aims to improve outcomes for all paediatric and adult patients with BMFS in Australia by describing the demographics, treatments (including supportive care) and outcomes, and serving as a resource for research and practice improvement.

Determinants of passive antibody efficacy in SARS-CoV-2 infection: a systematic review and meta-analysis.

BACKGROUND: Randomised controlled trials of passive antibodies as treatment and prophylaxis for COVID-19 have reported variable efficacy. However, the determinants of efficacy have not been identified. We aimed to assess how the dose and timing of administration affect treatment outcome. METHODS: In this systematic review and meta-analysis, we extracted data from published studies of passive antibody treatment from Jan 1, 2019, to Jan 31, 2023, that were identified by searching multiple databases, including MEDLINE, PubMed, and ClinicalTrials.gov. We included only randomised controlled trials of passive antibody administration for the prevention or treatment of COVID-19. To compare administered antibody dose between different treatments, we used data on in-vitro neutralisation titres to normalise dose by antibody potency. We used mixed-effects regression and model fitting to analyse the relationship between timing, dose and efficacy. FINDINGS: We found 58 randomised controlled trials that investigated passive antibody therapies for the treatment or prevention of COVID-19. Earlier clinical stage at treatment initiation was highly predictive of the efficacy of both monoclonal antibodies (p<0·0001) and convalescent plasma therapy (p=0·030) in preventing progression to subsequent stages, with either prophylaxis or treatment in outpatients showing the greatest effects. For the treatment of outpatients with COVID-19, we found a significant association between the dose administered and efficacy in preventing hospitalisation (relative risk 0·77; p<0·0001). Using this relationship, we predicted that no approved monoclonal antibody was expected to provide more than 30% efficacy against some omicron (B.1.1.529) subvariants, such as BQ.1.1. INTERPRETATION: Early administration before hospitalisation and sufficient doses of passive antibody therapy are crucial to achieving high efficacy in preventing clinical progression. The relationship between dose and efficacy provides a framework for the rational assessment of future passive antibody prophylaxis and treatment strategies for COVID-19. FUNDING: The Australian Government Department of Health, Medical Research Future Fund, National Health and Medical Research Council, the University of New South Wales, Monash University, Haematology Society of Australia and New Zealand, Leukaemia Foundation, and the Victorian Government.

Simvastatin in Critically Ill Patients with Covid-19.

BACKGROUND: The efficacy of simvastatin in critically ill patients with coronavirus disease 2019 (Covid-19) is unclear. METHODS: In an ongoing international, multifactorial, adaptive platform, randomized, controlled trial, we evaluated simvastatin (80 mg daily) as compared with no statin (control) in critically ill patients with Covid-19 who were not receiving statins at baseline. The primary outcome was respiratory and cardiovascular organ support-free days, assessed on an ordinal scale combining in-hospital death (assigned a value of -1) and days free of organ support through day 21 in survivors; the analyis used a Bayesian hierarchical ordinal model. The adaptive design included prespecified statistical stopping criteria for superiority (>99% posterior probability that the odds ratio was >1) and futility (>95% posterior probability that the odds ratio was <1.2). RESULTS: Enrollment began on October 28, 2020. On January 8, 2023, enrollment was closed on the basis of a low anticipated likelihood that prespecified stopping criteria would be met as Covid-19 cases decreased. The final analysis included 2684 critically ill patients. The median number of organ support-free days was 11 (interquartile range, -1 to 17) in the simvastatin group and 7 (interquartile range, -1 to 16) in the control group; the posterior median adjusted odds ratio was 1.15 (95% credible interval, 0.98 to 1.34) for simvastatin as compared with control, yielding a 95.9% posterior probability of superiority. At 90 days, the hazard ratio for survival was 1.12 (95% credible interval, 0.95 to 1.32), yielding a 91.9% posterior probability of superiority of simvastatin. The results of secondary analyses were consistent with those of the primary analysis. Serious adverse events, such as elevated levels of liver enzymes and creatine kinase, were reported more frequently with simvastatin than with control. CONCLUSIONS: Although recruitment was stopped because cases had decreased, among critically ill patients with Covid-19, simvastatin did not meet the prespecified criteria for superiority to control. (REMAP-CAP ClinicalTrials.gov number, NCT02735707.).

Definitions of massive transfusion in adults with critical bleeding: a systematic review.

BACKGROUND: Definitions for massive transfusion (MT) vary widely between studies, contributing to challenges in interpretation of research findings and practice evaluation. In this first systematic review, we aimed to identify all MT definitions used in randomised controlled trials (RCTs) to date to inform the development of consensus definitions for MT. METHODS: We systematically searched the following databases for RCTs from inception until 11 August 2022: MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Cumulative Index to Nursing and Allied Health Literature, and Transfusion Evidence Library. Ongoing trials were sought from CENTRAL, ClinicalTrials.gov, and World Health Organisation International Clinical Trials Registry Platform. To be eligible for inclusion, studies had to fulfil all the following three criteria: (1) be an RCT; (2) include an adult patient population with major bleeding who had received, or were anticipated to receive, an MT in any clinical setting; and (3) specify a definition for MT as an inclusion criterion or outcome measure. RESULTS: Of the 8,458 distinct references identified, 30 trials were included for analysis (19 published, 11 ongoing). Trauma was the most common clinical setting in published trials, while for ongoing trials, it was obstetrics. A total of 15 different definitions of MT were identified across published and ongoing trials, varying greatly in cut-offs for volume transfused and time period. Almost all definitions specified the number of red blood cells (RBCs) within a set time period, with none including plasma, platelets or other haemostatic agents that are part of contemporary transfusion resuscitation. For completed trials, the most commonly used definition was transfusion of ≥ 10 RBC units in 24 h (9/19, all in trauma), while for ongoing trials it was 3-5 RBC units (n = 7), with the timing for transfusion being poorly defined, or in some trials not provided at all (n = 5). CONCLUSIONS: Transfusion of ≥ 10 RBC units within 24 h was the most commonly used definition in published RCTs, while lower RBC volumes are being used in ongoing RCTs. Any consensus definitions should reflect the need to incorporate different blood components/products for MT and agree on whether a 'one-size-fits-all' approach should be used across different clinical settings.

Monoclonal antibody levels and protection from COVID-19.

Multiple monoclonal antibodies have been shown to be effective for both prophylaxis and therapy for SARS-CoV-2 infection. Here we aggregate data from randomized controlled trials assessing the use of monoclonal antibodies (mAb) in preventing symptomatic SARS-CoV-2 infection. We use data on the in vivo concentration of mAb and the associated protection from COVID-19 over time to model the dose-response relationship of mAb for prophylaxis. We estimate that 50% protection from COVID-19 is achieved with a mAb concentration of 96-fold of the in vitro IC50 (95% CI: 32-285). This relationship provides a tool for predicting the prophylactic efficacy of new mAb and against SARS-CoV-2 variants. Finally, we compare the relationship between neutralization titer and protection from COVID-19 after either mAb treatment or vaccination. We find no significant difference between the 50% protective titer for mAb and vaccination, although sample sizes limited the power to detect a difference.

Effect of Low-Dose Aspirin Versus Placebo on Incidence of Anemia in the Elderly : A Secondary Analysis of the Aspirin in Reducing Events in the Elderly Trial.

BACKGROUND: Daily low-dose aspirin increases major bleeding; however, few studies have investigated its effect on iron deficiency and anemia. OBJECTIVE: To investigate the effect of low-dose aspirin on incident anemia, hemoglobin, and serum ferritin concentrations. DESIGN: Post hoc analysis of the ASPREE (ASPirin in Reducing Events in the Elderly) randomized controlled trial. (ClinicalTrials.gov: NCT01038583). SETTING: Primary/community care in Australia and the United States. PARTICIPANTS: Community-dwelling persons aged 70 years or older (≥65 years for Black persons and Hispanic persons). INTERVENTION: 100 mg of aspirin daily or placebo. MEASUREMENTS: Hemoglobin concentration was measured annually in all participants. Ferritin was measured at baseline and 3 years after random assignment in a large subset. RESULTS: 19 114 persons were randomly assigned. Anemia incidence in the aspirin and placebo groups was 51.2 events and 42.9 events per 1000 person-years, respectively (hazard ratio, 1.20 [95% CI, 1.12 to 1.29]). Hemoglobin concentrations declined by 3.6 g/L per 5 years in the placebo group and the aspirin group experienced a steeper decline by 0.6 g/L per 5 years (CI, 0.3 to 1.0 g/L). In 7139 participants with ferritin measures at baseline and year 3, the aspirin group had greater prevalence than placebo of ferritin levels less than 45 µg/L at year 3 (465 [13%] vs. 350 [9.8%]) and greater overall decline in ferritin by 11.5% (CI, 9.3% to 13.7%) compared with placebo. A sensitivity analysis quantifying the effect of aspirin in the absence of major bleeding produced similar results. LIMITATIONS: Hemoglobin was measured annually. No data were available on causes of anemia. CONCLUSION: Low-dose aspirin increased incident anemia and decline in ferritin in otherwise healthy older adults, independent of major bleeding. Periodic monitoring of hemoglobin should be considered in older persons on aspirin. PRIMARY FUNDING SOURCE: National Institutes of Health and Australian National Health and Medical Research Council.

Pre-hospital freeze-dried plasma for critical bleeding after trauma: A pilot randomized controlled trial.

OBJECTIVES: Transfusion of a high ratio of plasma to packed red blood cells (PRBCs), to treat or prevent acute traumatic coagulopathy, has been associated with survival after major trauma. However, the effect of prehospital plasma on patient outcomes has been inconsistent. The aim of this pilot trial was to assess the feasibility of transfusing freeze-dried plasma with red blood cells (RBCs) using a randomized controlled design in an Australian aeromedical prehospital setting. METHODS: Patients attended by helicopter emergency medical service (HEMS) paramedics with suspected critical bleeding after trauma managed with prehospital RBCs were randomized to receive 2 units of freeze-dried plasma (Lyoplas N-w) or standard care (no plasma). The primary outcome was the proportion of eligible patients enrolled and provided the intervention. Secondary outcomes included preliminary data on effectiveness, including mortality censored at 24 h and at hospital discharge, and adverse events. RESULTS: During the study period of June 1 to October 31, 2022, there were 25 eligible patients, of whom 20 (80%) were enrolled in the trial and 19 (76%) received the allocated intervention. Median time from randomization to hospital arrival was 92.5 min (IQR 68-101.5 min). Mortality may have been lower in the freeze-dried plasma group at 24 h (RR 0.24, 95% CI 0.03-1.73) and at hospital discharge (RR 0.73, 95% CI 0.24-2.27). No serious adverse events related to the trial interventions were reported. CONCLUSIONS: This first reported experience of freeze-dried plasma use in Australia suggests prehospital administration is feasible. Given longer prehospital times typically associated with HEMS attendance, there is potential clinical benefit from this intervention and rationale for a definitive trial.

Current and future strategies to monitor and manage coagulation in ECMO patients.

Extracorporeal membrane oxygenation (ECMO) can provide life-saving support for critically ill patients suffering severe respiratory and/or cardiac failure. However, thrombosis and bleeding remain common and complex problems to manage. Key causes of thrombosis in ECMO patients include blood contact to pro-thrombotic and non-physiological surfaces, as well as high shearing forces in the pump and membrane oxygenator. On the other hand, adverse effects of anticoagulant, thrombocytopenia, platelet dysfunction, acquired von Willebrand syndrome, and hyperfibrinolysis are all established as causes of bleeding. Finding safe and effective anticoagulants that balance thrombosis and bleeding risk remains challenging. This review highlights commonly used anticoagulants in ECMO, including their mechanism of action, monitoring methods, strengths and limitations. It further elaborates on existing anticoagulant monitoring strategies, indicating their target range, benefits and drawbacks. Finally, it introduces several highly novel approaches to real-time anticoagulation monitoring methods including sound, optical, fluorescent, and electrical measurement as well as their working principles and future directions for research.

Clinical characteristics of Australian treatment-naïve patients with classical Hodgkin lymphoma from the lymphoma and related diseases registry.

Comprehensive clinical characteristics of Australian patients with classical Hodgkin Lymphoma (cHL) have not previously been systematically collected and described. We report real-world data of 498 eligible patients from the first 5 years of the Lymphoma and Related Diseases Registry (LaRDR), including baseline characteristics, histologic subtype, and treatment patterns in first-line therapy. Patient demographics and distribution of histopathological subtypes of cHL are similar to reported international cohorts. Doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) was the most common therapy for both early and advanced-stage disease, and 48% of patients with the early-stage disease received radiotherapy. Treatment patterns are consistent with international guidelines. In comorbid patients ≥60 years of age with advanced-stage disease, there is greater variation in treatment. In patients with a recorded response, the objective response rate (ORR) was 96% in early-stage disease, and 88% in advanced-stage disease. Early progression-free survival data suggest Australian patients with cHL have good outcomes, similar to other international studies.

Red blood cell alloantibodies in the context of critical bleeding and massive transfusion.

BACKGROUND: In the context of critical bleeding and massive transfusion (CB/MT), little is known about the development of new red blood cell (RBC) alloantibodies. We performed a retrospective, observational study to examine the frequency of RBC alloantibodies (pre-existent, anamnestic, or new) in patients with CB/MT, defined as transfusion of five or more RBC units in any 4-hour period, for any cause of CB. MATERIALS AND METHODS: Data on 2,585 New Zealand patients (date/time of MT initiation, demographic data, blood group, clinical context, and transfused RBCs) were obtained from the Australian and New Zealand Massive Transfusion Registry. RBC alloantibody screening/identification data were extracted from the New Zealand Blood Service database. We calculated summary statistics, compared proportions between different independent groups using the Chi-squared test, and performed logistic regression analysis to examine the effects of variables on alloantibody presence or formation. We also determined the immunogenicities of selected RBC antigens in the context of CB/MT. RESULTS: Of 1,234 assessable patients, 1,166 (94.5%) showed no evidence of any alloantibody. Pre-existent, anamnestic, and new alloantibodies were found, respectively, in 4.3%, 0.4%, and 7.2% of assessable patients. By multivariable regression analysis, transfusion of D-positive RBC to D-negative patients was independently associated with new alloantibody formation. Neither the quantum of RBC transfused nor trauma as clinical context were so associated although the latter trended towards a predisposition. "Antibodies of undetermined specificity" were the commonest pre-existent and new alloantibodies. The immunogenicity of Jka was the highest in this setting. DISCUSSION: RBC alloantibodies of any type were rare in this CB/MT population. Patients undergoing CB/MT appear to have low risks of re-stimulating anamnestic alloantibodies, or of developing new RBC alloantibodies.