Building the blueprint: Formulating a community-generated national plan for future research in inherited bleeding disorders.

INTRODUCTION: Decades of inherited bleeding disorders (BD) research transformed severe haemophilia from a childhood killer to a disorder managed across a full lifespan for many in economically developed countries. Health equity, a life unimpaired by disease complications, however, remains unimaginable for most people with an inherited BD (PWIBD). AIM: The National Hemophilia Foundation (NHF) and American Thrombosis and Hemostasis Network (ATHN) undertook the development of a community-driven United States (US) National Blueprint for Inherited Bleeding Disorders Research to transform the experience of all PWIBD and those who care for them. METHODS: Extensive community consultations were conducted to identify the issues most important to PWIBD and those who love and care for them. Expert multidisciplinary teams distilled these key areas of need into prioritised research questions, and identified the resources and infrastructure required to pursue them. A summit was held to gather feedback and inform the detailed blueprint. RESULTS: Community-prioritised research areas fell into three broad categories: issues common across inherited BDs, those specific to individual disorders, and issues of infrastructure and capacity. NHF State of the Science Research Summit discussions of the research questions derived from the community priorities by six working groups provided important input for the drafting of the research blueprint for the coming decades. CONCLUSION: The inherited BD community came together to develop the US National Blueprint for Inherited Bleeding Disorders Research dedicated to transforming the lives of all PWIBD including innovating solutions for the rarest disorders and under-represented populations.

Big picture initiatives in bleeding disorders.

INTRODUCTION: The inherited bleeding disorders (IBD) community has witnessed significant therapeutic advances recently, yet important gaps persist, particularly for those with rare disorders and historically underserved populations. AIMS: -To create a national research blueprint agenda, led by the National Hemophilia Foundation (NHF), enhancing patient-centric principles, accelerate research progress and address important gaps in care. -To review critical gaps that remain to be addressed in women with IBDs, who face specific bleeding challenges. METHODS: The NHF research blueprint research agenda was defined by input from across the community, including caregivers and patients who are considered subject matter experts of their IBD, research leaders, allied health professionals and specialists, and representatives of the biopharmaceutical industry. In addition, two medical experts in the field of IBDs performed a comprehensive review to address the knowledge gaps in women with IBDs. RESULTS: Two foundational principles of the NHF blueprint are: (1) it must deliver on key issues that significantly impact the lives of those affected by IBDs, and (2) the priorities defined are relevant and actionable aimed to achieve health equity among all those affected by IBDs. A multidisciplinary approach is necessary for an optimal management of puberty, transition to adulthood and pregnancy. Even if strict guidelines are followed, recent studies show that women with IBDs are still facing a high burden. CONCLUSION: NHF blueprint will be issued in 2022. A specific research agenda is needed in women with IBDs to further improve their management and quality of life.

Origins and organization of the NHLBI State of the Science Workshop: Generating a national blueprint for future research on factor VIII inhibitors.

INTRODUCTION: The major complication of protein replacement therapy for haemophilia A is the development of anti-FVIII antibodies or inhibitors that occur in 25%-30% of persons with severe haemophilia A. Alternative therapeutics such as bypassing agents or immune tolerance induction protocols have additional challenges and are not always effective. AIM: Assemble a National Heart, Lung and Blood Institute (NHLBI) State of the Science (SOS) Workshop to generate a national blueprint for research on inhibitors to solve the problem of FVIII immunogenicity. METHODS: An Executive Steering Committee was formed in October 2017 to establish the scientific focus and Scientific Working Groups for the SOS Workshop in May 2018. Four working groups were assembled to address scientific priorities in basic, translational and clinical research on inhibitors. RESULTS: Working Group 1 was charged with determining the scientific priorities for clinical trials to include the integration of non-intravenous, non-factor therapeutics including gene therapy into the standard of care for people with haemophilia A with inhibitors. Working Group 2 established the scientific priorities for 21st-century data science and biospecimen collection for observational inhibitor cohort studies. The scientific priorities for acquiring an actionable understanding of FVIII immunogenicity and the immunology of the host response and FVIII tolerance were developed by Working Group 3. Working Group 4 designed prospective pregnancy/birth cohorts to study FVIII immunogenicity, inhibitor development and eradication. CONCLUSION: The NHLBI SOS Workshop generated a focused summary of scientific priorities and implementation strategies to overcome the challenges of eradicating and preventing inhibitors in haemophilia A.

Planning for the future workforce in hematology research.

The medical research and training enterprise in the United States is complex in both its scope and implementation. Accordingly, adaptations to the associated workforce needs present particular challenges. This is particularly true for maintaining or expanding national needs for physician-scientists where training resource requirements and competitive transitional milestones are substantial. For the individual, these phenomena can produce financial burden, prolong the career trajectory, and significantly influence career pathways. Hence, when national data suggest that future medical research needs in a scientific area may be met in a less than optimal manner, strategies to expand research and training capacity must follow. This article defines such an exigency for research and training in nonneoplastic hematology and presents potential strategies for addressing these critical workforce needs. The considerations presented herein reflect a summary of the discussions presented at 2 workshops cosponsored by the National Heart, Lung, and Blood Institute and the American Society of Hematology.

Citation impact of NHLBI R01 grants funded through the American Recovery and Reinvestment Act as compared to R01 grants funded through a standard payline.

RATIONALE: The American Recovery and Reinvestment Act (ARRA) allowed National Heart, Lung, and Blood Institute to fund R01 grants that fared less well on peer review than those funded by meeting a payline threshold. It is not clear whether the sudden availability of additional funding enabled research of similar or lesser citation impact than already funded work. OBJECTIVE: To compare the citation impact of ARRA-funded de novo National Heart, Lung, and Blood Institute R01 grants with concurrent de novo National Heart, Lung, and Blood Institute R01 grants funded by standard payline mechanisms. METHODS AND RESULTS: We identified de novo (type 1) R01 grants funded by National Heart, Lung, and Blood Institute in fiscal year 2009: these included 458 funded by meeting Institute's published payline and 165 funded only because of ARRA funding. Compared with payline grants, ARRA grants received fewer total funds (median values, $1.03 versus $1.87 million; P<0.001) for a shorter duration (median values including no-cost extensions, 3.0 versus 4.9 years; P<0.001). Through May 2014, the payline R01 grants generated 3895 publications, whereas the ARRA R01 grants generated 996. Using the InCites database from Thomson-Reuters, we calculated a normalized citation impact for each grant by weighting each article for the number of citations it received normalizing for subject, article type, and year of publication. The ARRA R01 grants had a similar normalized citation impact per $1 million spent as the payline grants (median values [interquartile range], 2.15 [0.73-4.68] versus 2.03 [0.75-4.10]; P=0.61). The similar impact of the ARRA grants persisted even after accounting for potential confounders. CONCLUSIONS: Despite shorter durations and lower budgets, ARRA R01 grants had comparable citation outcomes per $million spent to that of contemporaneously funded payline R01 grants.

Prior publication productivity, grant percentile ranking, and topic-normalized citation impact of NHLBI cardiovascular R01 grants.

RATIONALE: We previously demonstrated absence of association between peer-review-derived percentile ranking and raw citation impact in a large cohort of National Heart, Lung, and Blood Institute cardiovascular R01 grants, but we did not consider pregrant investigator publication productivity. We also did not normalize citation counts for scientific field, type of article, and year of publication. OBJECTIVE: To determine whether measures of investigator prior productivity predict a grant's subsequent scientific impact as measured by normalized citation metrics. METHODS AND RESULTS: We identified 1492 investigator-initiated de novo National Heart, Lung, and Blood Institute R01 grant applications funded between 2001 and 2008 and linked the publications from these grants to their InCites (Thompson Reuters) citation record. InCites provides a normalized citation count for each publication stratifying by year of publication, type of publication, and field of science. The coprimary end points for this analysis were the normalized citation impact per million dollars allocated and the number of publications per grant that has normalized citation rate in the top decile per million dollars allocated (top 10% articles). Prior productivity measures included the number of National Heart, Lung, and Blood Institute-supported publications each principal investigator published in the 5 years before grant review and the corresponding prior normalized citation impact score. After accounting for potential confounders, there was no association between peer-review percentile ranking and bibliometric end points (all adjusted P>0.5). However, prior productivity was predictive (P<0.0001). CONCLUSIONS: Even after normalizing citation counts, we confirmed a lack of association between peer-review grant percentile ranking and grant citation impact. However, prior investigator publication productivity was predictive of grant-specific citation impact.

The polygenic nature of inhibitors in hemophilia A: results from the Hemophilia Inhibitor Genetics Study (HIGS) Combined Cohort.

Studies of determinants of development of inhibitory Abs to factor VIII in people with hemophilia A indicate a complex process involving multiple factors. The Hemophilia Inhibitor Genetics Study (HIGS) Combined Cohort was formed to extend our understanding of the genetic background of risk. The study group contains 833 subjects from 3 independent cohorts: brother pairs and singletons with and without a history of inhibitors, as well as 104 brother pairs discordant for inhibitor status. Using an Illumina iSelect platform, 13 331 single-nucleotide polymorphisms from 1081 genes, primarily immune response and immune modifier genes, were typed. Each cohort was analyzed separately with results combined using a meta-analytic technique. After adjustment for potential confounders, 53 single-nucleotide polymorphisms were found to be significant predictors of inhibitor status using the criteria of odds ratios in the same direction in all cohorts or allowing for a 20% interval around an odds ratio = 1 in 1 of the 3 and significant in at least 2. Of the 53 markers, 13 had meta P < .001. Eight of the 53 were significant predictors among the discordant pairs. Results support the complexity of the immune response and encourage further research with the goal of understanding the pathways involved.

The principal results of the International Immune Tolerance Study: a randomized dose comparison.

The International Immune Tolerance Study was a multicenter, prospective, randomized comparison of high-dose (HD; 200 IU/kg/d) and low-dose (LD; 50 IU/kg 3 times/week) factor VIII regimens in 115 "good-risk," severe high-titer inhibitor hemophilia A subjects. Sixty-six of 115 subjects reached the defined study end points: success, n = 46 (69.7%); partial response, n = 3 (4.5%); and failure, n = 17 (25.8%). Successes did not differ between treatment arms (24 of 58 LD vs 22/57 HD, P = .909). The times taken to achieve a negative titer (P = .027), a normal recovery (P = .002), and tolerance (P = .116, nonsignificant) were shorter with the HD immune tolerance induction (ITI). Peak historical (P = .026) and on-ITI (P = .002) titers were correlated inversely with success, but only peak titer on ITI predicted outcome in a multivariate analysis (P = .002). LD subjects bled more often (odds ratio, 2.2; P = .0019). The early bleed rate/month was 0.62 (LD) and 0.28 (HD; P = .000 24), decreasing by 90% once negative titers were achieved. Bleeding was absent in 8 of 58 LD versus 21 of 57 HD subjects (P = .0085). One hundred twenty-four central catheter infections were reported in 41 subjects (19 LD); infection frequency did not differ between the treatment arms. Neither bleeding nor infection influenced outcome. Although it was stopped early for futility and safety considerations, this trial contributed valuable data toward evidence-based ITI practice.

National surveillance for hemophilia inhibitors in the United States: Summary report of an expert meeting.

On March 12, 2012, the Centers for Disease Control and Prevention (CDC) held a meeting of its partners in hemophilia treatment, community-based organizations, industry, and government to review data and discuss implementation issues relevant to planned United States (U.S.) national inhibitor surveillance. Issues discussed included the current status of inhibitor surveillance in the United Kingdom (UK) and the US, the results of a US inhibitor surveillance feasibility study, proposed national surveillance schemes, laboratory testing and reporting issues and potential opportunities for future inhibitor-related research. It was concluded that implementation of a national program of inhibitor surveillance using standardized testing through an established public health registry along with patient and care provider education and targeted research provide the best opportunity to inform efforts to develop and evaluate effective prevention strategies.

Neoangiogenesis contributes to the development of hemophilic synovitis.

Joint arthropathy secondary to recurrent hemarthroses remains a debilitating complication of hemophilia despite the use of prophylactic factor concentrates. Increased vascularity and neoangiogenesis have been implicated in the progression of musculoskeletal disorders and tumor growth. We hypothesized that de novo blood vessel formation could play a major role in the pathogenesis of hemophilic joint disease (HJD). We observed a 4-fold elevation in proangiogenic factors (vascular endothelial growth factor-A [VEGF-A], stromal cell-derived factor-1, and matrix metalloprotease-9) and proangiogenic macrophage/monocyte cells (VEGF(+)/CD68(+) and VEGFR1(+)/CD11b(+)) in the synovium and peripheral blood of HJD subjects along with significantly increased numbers of VEGFR2(+)/AC133(+) endothelial progenitor cells and CD34(+)/VEGFR1(+) hematopoietic progenitor cells. Sera from HJD subjects induced an angiogenic response in endothelial cells that was abrogated by blocking VEGF, whereas peripheral blood mononuclear cells from HJD subjects stimulated synovial cell proliferation, which was blocked by a humanized anti-VEGF antibody (bevacizumab). Human synovial cells, when incubated with HJD sera, could elicit up-regulation of HIF-1α mRNA with HIF-1α expression in the synovium of HJD subjects, implicating hypoxia in the neoangiogenesis process. Our results provide evidence of local and systemic angiogenic response in hemophilic subjects with recurrent hemarthroses suggesting a potential to develop surrogate biologic markers to identify the onset and progression of hemophilic synovitis.

Inhibitors in childhood hemophilia A: genetic and treatment-related risk factors for development and eradication.

The development of neutralizing antibodies remains a serious complication of hemophilia replacement therapy. Factor VIII inhibiting antibodies (inhibitors) occur commonly following replacement therapy in hemophilia A, creating a significant burden of clinical disease. This article will review our current understanding of risk factors and their known impact on inhibitor development in previously untreated or minimally treated children with severe and mild hemophilia A. It will also explore how the most recently elucidated immunology of inhibitor development might hold important clues to more effective inhibitor eradication and prevention in this heavily impacted patient population.

The National Hemophilia Foundation State of the Science Research Summit initiative: executive summary.

INTRODUCTION: The National Hemophilia Foundation State of the Science Research Summit initiative sought to unify research efforts in the US inherited bleeding disorders (BDs) community around key topics of importance to people living with inherited BDs, the lived experience experts. AREAS COVERED: This community-led and -informed project focused on six broad areas - hemophilia A or B; von Willebrand Disease (VWD), platelet dysfunctions and other mucocutaneous inherited BDs; ultra-rare inherited BDs; the unique challenges of people with the potential to menstruate with inherited BDs; diversity, equity and inclusion, health services research, and implementation science; and facilitating research in the inherited BD community through designing an optimizied research infrastructure, enabling resources and funding, and furthering workforce capabilities required to execute the research priorities. EXPERT OPINION: The work summarized here, and in the accompanying supplement manuscripts , has implications not only for the US population but for people globally who have inherited BDs. The information is equally relevant to people living with hemophilia, VWD, the spectrum of inherited platelet disorders, ultra-rare factor deficiencies, and all other inherited BDs as it is to the health care providers and researchers focused on the care and treatment of inherited BDs in the US and globally.

Immune tolerance in haemophilia: the long journey to the fork in the road.

Antibody eradication is the ultimate goal of inhibitor management. The only clinically proven strategy for achieving antigen-specific tolerance to factor VIII is immune tolerance induction (ITI). Our knowledge about ITI in haemophilia A and B was, historically, derived from small cohort studies and retrospective national and international ITI registries. Practice is now further influenced by prospective cohort data, and the results of a single prospective randomized international ITI trial. However, due to the low incidence of inhibitors in haemophilia B, there are few comparable data from which to develop a useful evidence-based approach to the prevention and eradication of factor IX inhibitors. The lack of an effective strategy is particularly problematic given the morbidity associated with the unique occurrence of allergic and anaphylactic reactions that often herald factor IX antibody development and preclude effective eradication. This paper will discuss our current understanding of immune tolerance outcome and outcome predictors for haemophilia A and B; review the current consensus practice recommendations for ITI; and summarize the emerging body of immunological science relating to antibody formation and tolerance. It will conclude by suggesting how our knowledge might inform the future investigative priorities impacting the therapeutic and preventative tolerance strategies of tomorrow.

Paroxysmal nocturnal hemoglobinuria in pediatric patients.

BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disease in children. The most significant clinical features of PNH include: bone marrow failure, intravascular hemolysis, and thrombosis. To further characterize the clinical presentation and outcome to treatment we performed a retrospective analysis of pediatric patients with PNH. PROCEDURE: We reviewed the medical records of 12 consecutive pediatric patients with PNH diagnosed at our institution from 1992 to 2010. RESULTS: Presenting clinical symptoms included: bone marrow failure (N = 10); gross hemoglobinuria with isolated red cell anemia (N = 1); and jaundice, hepatitis, and isolated thrombocytopenia (N = 1). Immunosuppressive therapy was the initial treatment for 8 patients. Five patients had myelodysplastic features without developing excessive blasts or leukemic transformation. Thrombosis occurred in 6 patients. Five patients underwent hematopoietic stem cell transplant (HSCT) of whom 3 patients are alive and disease-free. Three patients received anti-complement therapy with eculizumab. Two patients died following complications related to thrombosis and 2 patients are transfusion independent with stable disease. CONCLUSION: This report highlights a high rate of bone marrow failure along with a low rate of hemoglobinuria at presentation, a high rate of thrombosis, and for some patients the spontaneous resolution of myelodysplastic features. Delay in diagnosis is common and we recommend appropriate PNH testing in all patients with AA, MDS, unexplained Coombs-negative hemolysis, or thrombosis. While HSCT remains the only curative option the high prevalence of hemolysis and thrombosis should warrant the consideration of early treatment with anti-complement therapy.

Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia.

BACKGROUND: Effective ways to prevent arthropathy in severe hemophilia are unknown. METHODS: We randomly assigned young boys with severe hemophilia A to regular infusions of recombinant factor VIII (prophylaxis) or to an enhanced episodic infusion schedule of at least three doses totaling a minimum of 80 IU of factor VIII per kilogram of body weight at the time of a joint hemorrhage. The primary outcome was the incidence of bone or cartilage damage as detected in index joints (ankles, knees, and elbows) by radiography or magnetic resonance imaging (MRI). RESULTS: Sixty-five boys younger than 30 months of age were randomly assigned to prophylaxis (32 boys) or enhanced episodic therapy (33 boys). When the boys reached 6 years of age, 93% of those in the prophylaxis group and 55% of those in the episodic-therapy group were considered to have normal index-joint structure on MRI (P=0.006). The relative risk of MRI-detected joint damage with episodic therapy as compared with prophylaxis was 6.1 (95% confidence interval, 1.5 to 24.4). The mean annual numbers of joint and total hemorrhages were higher at study exit in the episodic-therapy group than in the prophylaxis group (P<0.001 for both comparisons). High titers of inhibitors of factor VIII developed in two boys who received prophylaxis; three boys in the episodic-therapy group had a life-threatening hemorrhage. Hospitalizations and infections associated with central-catheter placement did not differ significantly between the two groups. CONCLUSIONS: Prophylaxis with recombinant factor VIII can prevent joint damage and decrease the frequency of joint and other hemorrhages in young boys with severe hemophilia A. (ClinicalTrials.gov number, NCT00207597 [ClinicalTrials.gov].).

Successful cryoablation of atrioventricular nodal reentrant tachycardia in a child with hemophilia A.

We report the hematologic and invasive electrophysiologic management of a 12-year-old boy with mild hemophilia A (factor VIII deficiency) and atrioventricular nodal reentrant tachycardia. Thoughtful preparation with detailed input from the patient's comprehensive hemophilia center combined with vigilant pericatheterization hematologic management allowed for safe and successful cryoablation of this arrhythmia. Strategies for the management of patients with bleeding disorders who require invasive cardiac catheterization or surgery are reviewed.

Splenic infarction and subsequent splenic rupture in a patient with paroxysmal nocturnal hemoglobinuria and heparin-induced thrombocytopenia.

We describe a patient with paroxysmal nocturnal hemoglobinuria (PNH) and no previous history of thrombosis who presented with hepatic venous thromboses and subsequently developed splenic infarction and rupture requiring splenectomy while on anticoagulation therapy for the hepatic thromboses. The patient's anticoagulation was complicated by heparin-induced thrombocytopenia (HIT) highlighting the unique management challenge presented by PNH in combination with HIT.