Treatment of patients with hemophilia A and B has undergone significant advances during the past 2 decades. However, despite these advances, the development of antibodies that inhibit the function of ...infused clotting factor remains a major challenge and is considered the most significant complication of hemophilia treatment. This chapter reviews current tools available for the care of patients with inhibitors and highlights areas where progress is imminent or strongly needed. For management of bleeding, bypassing agents remain the mainstay of therapy. Recombinant factor VIIa and activated prothrombin complex concentrates are similarly effective in populations of patients with hemophilia and inhibitors; however, individuals may show a better response to one agent over another. Recent studies have shown that prophylaxis with bypassing agents can reduce bleeding episodes by ∼50%-80%. The prophylactic use of bypassing agents is an important tool to reduce morbidity in patients before they undergo immune tolerance induction (ITI) and in those with persistent high titer inhibitors, but cost and lack of convenience remain barriers. Because of the significant burden that inhibitors add to the individual patient and the health care system, inhibitor eradication should be pursued in as many patients as possible. ITI is an effective tool, particularly in patients with severe hemophilia A and good risk profiles, and leads to a return to a normal factor VIII response in ∼60% of patients. However, for the group of patients who fail to respond to ITI or have hemophilia B, new and improved tools are needed.
Acquired hemophilia A (AHA) is a rare disease resulting from autoantibodies (inhibitors) against endogenous factor VIII (FVIII) that leads to bleeding, which is often spontaneous and severe. AHA ...tends to occur in elderly patients with comorbidities and is associated with high mortality risk from underlying comorbidities, bleeding, or treatment complications. Treatment, which consists of hemostatic management and eradication of the inhibitors, can be challenging to manage.
Few data are available to guide the management of AHA‐related bleeding and eradication of the disease‐causing antibodies. Endorsed by the Hemostasis and Thrombosis Research Society of North America, an international panel of experts in AHA analyzed key questions, reviewed the literature, weighed the evidence and formed a consensus to update existing guidelines.
AHA is likely underdiagnosed and misdiagnosed in real‐world clinical practice. Recommendations for the management of AHA are summarized here based on the available data, integrated with the clinical experience of panel participants.
Emicizumab is a bispecific monoclonal antibody that bridges activated factor IX and factor X to replace the function of missing activated factor VIII, thereby restoring hemostasis. In a phase 3, ...multicenter trial, we investigated its use as prophylaxis in persons who have hemophilia A without factor VIII inhibitors.
We randomly assigned, in a 2:2:1 ratio, participants 12 years of age or older who had been receiving episodic treatment with factor VIII to receive a subcutaneous maintenance dose of emicizumab of 1.5 mg per kilogram of body weight per week (group A) or 3.0 mg per kilogram every 2 weeks (group B) or no prophylaxis (group C). The primary end point was the difference in rates of treated bleeding (group A vs. group C and group B vs. group C). Participants who had been receiving factor VIII prophylaxis received emicizumab at a maintenance dose of 1.5 mg per kilogram per week (group D); intraindividual comparisons were performed in those who had participated in a noninterventional study.
A total of 152 participants were enrolled. The annualized bleeding rate was 1.5 events (95% confidence interval CI, 0.9 to 2.5) in group A and 1.3 events (95% CI, 0.8 to 2.3) in group B, as compared with 38.2 events (95% CI, 22.9 to 63.8) in group C; thus, the rate was 96% lower in group A and 97% lower in group B (P<0.001 for both comparisons). A total of 56% of the participants in group A and 60% of those in group B had no treated bleeding events, as compared with those in group C, who all had treated bleeding events. In the intraindividual comparison involving 48 participants, emicizumab prophylaxis resulted in an annualized bleeding rate that was 68% lower than the rate with previous factor VIII prophylaxis (P<0.001). The most frequent adverse event was low-grade injection-site reaction. There were no thrombotic or thrombotic microangiopathy events, development of antidrug antibodies, or new development of factor VIII inhibitors.
Emicizumab prophylaxis administered subcutaneously once weekly or every 2 weeks led to a significantly lower bleeding rate than no prophylaxis among persons with hemophilia A without inhibitors; more than half the participants who received prophylaxis had no treated bleeding events. In an intraindividual comparison, emicizumab therapy led to a significantly lower bleeding rate than previous factor VIII prophylaxis. (Funded by F. Hoffmann-La Roche and Chugai Pharmaceutical; HAVEN 3 ClinicalTrials.gov number, NCT02847637 .).
The coronavirus disease (COVID-19) pandemic has threatened millions of lives worldwide with severe systemic inflammation, organ dysfunction, and thromboembolic disease. Within our institution, many ...critically ill COVID-19-positive patients suffered major thrombotic events, prompting our clinicians to evaluate hypercoagulability outside of traditional coagulation testing.We determined the prevalence of fibrinolysis shutdown via rotational thromboelastometry (ROTEM, Instrumentation Laboratories, Bedford, Mass) in patients admitted to the intensive care unit over a period of 3 weeks. In 25 patients who had a ROTEM test, we found that 11 (44%) met criteria for fibrinolysis shutdown. Eight of 9 (73%) of the VTE patients met criteria for fibrinolysis shutdown.Given the high rate of fibrinolysis shutdown in these patients, our data support using viscoelastic testing to evaluate for the presence of impaired fibrinolysis. This may help identify patient subsets who might benefit from the administration of fibrinolytics.
Immune tolerance induction (ITI) is the only treatment to eradicate inhibitors in people with severe haemophilia A with inhibitors. Since the risk of inhibitor development is greater among Black and ...Hispanic persons, it has been hypothesized that race and ethnicity may influence ITI success. Limited studies have evaluated this hypothesis.
To examine the success of ITI according to race and ethnicity.
Participants who entered the Community Counts (CC) Registry between 2013 and 2017, were aged ≥3 years at study entry, and received ITI were included (n = 559). The proportion of participants with successful ITI was examined with adjusted prevalence ratios (aPRs) and corresponding 95% confidence intervals (95% CIs).
Among 559 participants, 56.9%, 19.1%, 18.1% and 4.3% were Non-Hispanic (NH) White, NH Black, Hispanic and Asian, respectively, and 1.7% were coded as other or missing. Approximately 80% of Hispanic, NH Black and NH White participants had good/very good prognosis, defined as having a pre-ITI peak inhibitor of < 200 Bethesda Units per millilitre. Nearly 60% of participants (59.7%) achieved successful ITI, 20.7% and 19.5% experienced partially successful or failed ITI, respectively. Successful ITI was non-significantly lower in NH Black (54.2%; aPR = 0.95, 95% CI 0.62-1.44) and Hispanic (55.4%; aPR = 0.89, 95% CI 0.71-1.13) relative to NH White participants (62.6%).
In this study, 60% of participants in the CC Registry had successful ITI, consistent with previous studies. The proportion with successful ITI was generally comparable across racial and ethnic groups with similar prognosis. These findings do not support the hypothesis that ITI response varies according to race or ethnicity.
Management of comorbidities in haemophilia Kempton, Christine L.; Makris, Michael; Holme, Pål Andre
Haemophilia : the official journal of the World Federation of Hemophilia,
February 2021, 2021-Feb, 2021-02-00, 20210201, Letnik:
27, Številka:
S3
Journal Article
Recenzirano
Odprti dostop
With the introduction of clotting factor concentrates in the early 1970s, significant improvements in quality of life and life expectancy of persons with haemophilia (PWH) were realized. ...Unfortunately, as a result of transmission of HIV and hepatitis C virus (HCV) by contaminated concentrates in the 1980s, many of these gains were lost. Now with four decades of PWH unexposed to contaminated factor products and current treatments capable of suppressing and eliminating HIV and HCV, respectively, the survival rate is once again increasing. In addition to the usual comorbidities associated with advanced age in the general population, several specific issues occur in patients with bleeding disorders. This manuscript explores the incidence and management of the comorbidities of the ageing PWH with a focus on cardiovascular disease and osteoporosis.
There is limited data on the markers of coagulation and hemostatic activation (MOCHA) profile in Coronavirus disease 2019 (COVID-19) and its ability to identify COVID-19 patients at risk for ...thrombotic events and other complications.
Hospitalized patients with confirmed SARS-COV-2 from four Atlanta hospitals were included in this observational cohort study and underwent admission testing of MOCHA parameters (plasma d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, fibrin monomer). Clinical outcomes included deep vein thrombosis, pulmonary embolism, myocardial infarction, ischemic stroke, access line thrombosis, ICU admission, intubation and mortality.
Of 276 patients (mean age 59 ± 6.4 years, 47% female, 62% African American), 45 (16%) had a thrombotic endpoint. Each MOCHA parameter was independently associated with a thrombotic event (p<0.05) and ≥ 2 abnormalities was associated with thrombotic endpoints (OR 3.3, 95% CI 1.2-8.8) as were admission D-dimer ≥ 2000 ng/mL (OR 3.1, 95% CI 1.5-6.6) and ≥ 3000 ng/mL (OR 3.6, 95% CI 1.6-7.9). However, only ≥ 2 MOCHA abnormalities were associated with ICU admission (OR 3.0, 95% CI 1.7-5.2) and intubation (OR 3.2, 95% CI 1.6-6.4). MOCHA and D-dimer cutoffs were not associated with mortality. MOCHA with <2 abnormalities (26% of the cohort) had 89% sensitivity and 93% negative predictive value for a thrombotic endpoint.
An admission MOCHA profile is useful to risk-stratify COVID-19 patients for thrombotic complications and more effective than isolated d-dimer for predicting risk of ICU admission and intubation.
Hemophilia A is a congenital X-linked bleeding disorder caused by coagulation factor VIII (FVIII) deficiency. Routine infusion of factor replacement products is the current standard of care; however, ...the development of alloantibodies against FVIII remains a challenge. The treatment of hemophilia has undergone major advances over the past century to improve safety, effectiveness, manufacturing, and convenience of factor products. Major recent advances in the treatment of hemophilia A include the emergence of extended half-life products, factor VIII orthologs, and gene therapy products. Extended half-life products were designed to decrease the frequency of infusions, but only modest half-life extension is achieved. Factor VIII orthologs featuring lower cross-reactivity with anti-FVIII antibodies may be less susceptible to inactivation by inhibitors. Meanwhile, gene therapy may potentially provide a cure for hemophilia A, thus abrogating the need for protein-based factor replacement. This review aims to discuss current and emerging FVIII replacement products for hemophilia A.
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