Search Results (130)

Background/Objectives: Patients with severe hemophilia A on prophylaxis with emicizumab exhibit a mild/moderate bleeding phenotype that requires the use of either recombinant FVIII (rFVIII) or bypassing agents (BPAs) in patients with inhibitors, in the case of breakthrough bleeding or surgery. Since factor IX (FIX) limits the formation of the FIXa–emicizumab–FX complex, exogenously added FIX might enhance complex formation and thrombin generation. This study aimed to compare the procoagulant effects of various FIX concentrates with recombinant activated FVII (rFVIIa), activated prothrombin complex concentrate (aPCC), and rFVIII in SHA patients with and without inhibitors under emicizumab prophylaxis. Methods: Hemostatic changes were monitored using two optimized global coagulation assays: rotational thromboelastometry and calibrated automated thrombin generation. Tubes containing corn trypsin inhibitor (CTI) were used during blood collection to prevent activation. Low concentrations of tissue factor (TF) were used to trigger coagulation in both assays. Results: Ex vivo addition of recombinant FIX concentrates significantly increased the procoagulant activity of emicizumab, achieving levels comparable to therapeutic doses of rFVIIa or rFVIII, and the proportion of active FIXa within the concentrates is a major contributor to their procoagulant function. We assessed the influence of FVIII inhibitors on the hemostatic efficacy of rFIX concentrates and BPAs, finding that rFIX-induced thrombin generation increased in the presence of inhibitors, and no significant differences were observed with BPAs. Conclusions: These findings suggest that FIX concentrates could be an effective alternative to BPAs for emicizumab-treated patients, particularly those with inhibitors. Further studies are needed to confirm their in vivo efficacy and to evaluate thrombotic risk. Full article

NKAP (NF-kappa-B-activating protein) is a ubiquitously expressed nuclear protein involved in multiple biological processes. Males with missense NKAP mutations have been reported to present with marfanoid features and behavioral and musculoskeletal abnormalities. We have previously reported that a disruptive NKAP mutation resulted in extremely skewed X chromosome inactivation (XCI), leading to phenotypic manifestation of hemophilia A (HA) in a HA carrier. In this study, with the aim of exploring the phenotypic manifestations of deleterious NKAP mutations in males, as well as their involvement in the mechanism of XCI regulation in females, we generated NKAP mutant mice using CRISPR/Cas9 technology. Gait analysis studies conducted in male mice hemizygous for mutant NKAP by the CatWalk XT system revealed significant alterations in gait parameters, consistent with hypotonia reported in human mutant NKAP patients. By breeding mutant NKAP mice with HA mice, we generated a double heterozygous mutant NKAP/HA mouse model, i.e., female mice carrying mutant NKAP with a WT F8 copy on one X chromosome, and WT NKAP with a mutant F8 copy on the other X chromosome. XCI pattern analysis using methylation-sensitive restriction enzymes demonstrated that mutant NKAP/HA females exhibited significant XCI skewing of the X chromosome bearing the mutant NKAP copy. Furthermore, these females exhibited significantly reduced F8 mRNA levels and FVIII (factor VIII) antigen levels, as demonstrated by quantitative RT-PCR and ELISA, respectively. Murine embryonic fibroblasts (MEFs) derived from a hemizygous mutant NKAP embryo exhibited markedly reduced proliferation rate and increased senescence compared to WT NKAP MEFs, suggesting that XCI skewing induced by mutant NKAP results from secondary selection against cells with an active X chromosome bearing the mutant NKAP copy. Full article

Legg–Calvé–Perthes disease (LCPD) is a rare disease caused by avascular necrosis of the femoral head. Although its etiology is still not fully understood, evidence suggests that heritable prothrombotic and inflammatory factors, as well as environmental factors, may be implicated in its onset and progress. The objective of this study is to describe the genetic, biochemical, and environmental factors that may be associated with the etiology of LCPD. This study was conducted in three families and included seven related patients with an LCPD diagnosis. We evaluated the following gene alterations using real-time PCR: MTHFR, CBS, COL1A1, COL2A1, PT, FVL, FVIII, FIX, PAI-1, eNOS, IL-23R, TNF-α, RANNK, RANNK-L, OPG and IL-6. Additionally, we assessed fourteen thrombophilia-associated biochemical markers, as well as environmental factors that may be associated with the etiology of LCPD in family cases. The results show different hemostatic alterations in every individual analyzed, presenting out-of-range values in one or more parameters. Concentrations of hemoglobin and fibrinogen and the FIX activity percentage showed statistically significant differences (p < 0.001) when compared with healthy controls. All patients presented at least one mutated allele for the MTFHR (rs1801133), IL-23R (rs1569922) and OPG (rs2073618) polymorphisms, as well as isolated cases with other genetic variants. Our results show environmental elements from every family, and hemostatic and inflammatory disorders, may be involved in the development of LCPD. Furthermore, genetic variants could contribute to the onset of the disease. This study highlights the multifactorial nature of this pathology, involving various environmental, genetic, inflammatory, and prothrombotic factors in three families that included seven patients diagnosed with LCPD. Full article

Background/Objectives: Autoimmune factor VIII deficiency (AiFVIIID) is a rare disorder that causes severe bleeding. Emicizumab has recently been found to be effective in treating AiFVIIID; however, monitoring with standard coagulation tests presents challenges. Methods: Clot waveform analysis (CWA), which involves CWA-activated partial thromboplastin time (APTT), the CWA-small amount of tissue factor activation assay (sTF/FIXa), and clotting time using a small amount of thrombin (sTT), was used to both diagnose AiFVIIID and monitor emicizumab. Results: CWA-sTT reflects the residual FVIII activity in patients with AiFVIIID. Several tests were employed, including APTT, FVIII activity, CWA, mixing tests with normal plasma, FVIII inhibitor assays, and anti-FVIII antibody activity for the diagnosis of AiFVIID in three cases. However, the sensitivity of APTT reagents to AiFVIID differed between thrombocheck-APTT and APTT-SP. Emicizumab treatment was effective for major bleeding, and anti-FVIII antibody activity could be measured using CWA-sTT. Conclusions: The sensitivity of APTT reagents to AiFVIID varies. CWA-sTT may provide utility in the diagnosis of AiFVIIID. Emicizumab is useful for the treatment of AiFVIID, and anti-FVIII antibody activity can be measured even in patients treated with emicizumab. Full article

Background: Acquired haemophilia A (AHA) is a rare autoimmune disorder characterized by the development of autoantibodies against Factor VIII activity, leading to a significant reduction in its functionality. Clinically, AHA presents with an unexpected prolongation of activated partial thromboplastin time (aPTT) and spontaneous bleeding episodes in patients without any personal or family history of haemorrhages. Bleeding manifestations can be severe at presentation, making early diagnosis and prompt treatment essential to reduce morbidity and mortality. Methods: We report on a single-centre cohort of 35 patients with AHA (examined from 1984 to 2024), analysing their demographics, underlying conditions, bleeding characteristics, treatment and outcome. Results: The median age of patients at diagnosis was 69 years (ranging from 18 to 92), 15 were males and 20 females. AHA was idiopathic in 37% of cases, severe bleeding was observed in 54% of patients treated with bypassing agents. Recombinant activated Factor VII (rFVIIa) was administered in 79% of cases and activated prothrombin complex concentrate (aPCC) in 10%, with no significant differences in haemostatic response and no thromboembolic complications. Occurrence of major bleeding showed no significant association with sex, age group, underlying condition, baseline Factor VIII activity or inhibitor titre at diagnosis. A total of 69% of patients were treated with corticosteroids alone, and 23% received a combination of corticosteroids and cyclophosphamide. Two patients died, six were lost to follow-up after partial remission, and one relapsed without bleeds after complete remission. Statistical analyses highlighted that the FVIII inhibitor titre > 20 BU was the only significant prognostic factor affecting time to complete remission. Conclusions: These observations emphasize the critical role of clinical suspicion and timely referral to experienced centres with adequate laboratory support for the effective management of AHA. Full article

The therapeutic clotting factor VIII (FVIII) is known for its particular immunogenicity, with nearly 30% of hemophilic patients developing neutralizing antibodies against the infused protein. The root cause of this immunogenicity is still not well understood, but intrinsic factors, such as FVIII byproducts, have been linked to the immunological response elicited. Bioengineering of the FVIII molecule has been improving its recombinant (rhFVIII) production in many aspects, mainly enhancing its expression and stability. Assessment of immunogenicity for novel recombinant isoforms is crucial for further development and scaling-up processes, particularly due to the unpredictable antigenic properties and their impact on neutralizing antibody formation. In the present study, we describe a bioengineered human recombinant FVIII (rhFVIII-H6A), which induces lower immunogenicity in a murine model of hemophilia A. The rhFVIII-H6A product is characterized by a B-domain-deleted heavy chain (HCh), with the C-terminal of the B-domain fused to the light chain (BΔ-LCh). Compared to plasma-derived FVIII (pdFVIII) and rhFVIII reference products, treating hemophilic mice with rhFVIII-H6A induced lower levels of anti-FVIII antibody formation, including those with inhibitory neutralizing activity, while no difference was observed in the functional activity of rhFVIII-H6A in reverting the in vivo hemophilia phenotype. In addition, our results indicate that deleting the major part of the B-domain from the HCh might lower the immunogenicity of novel rhFVIII products. Full article

Objective: This study aimed to analyze pharmacokinetic and clinical parameters (bleeding rates and joint health) before and after switching from standard half-life (SHL) factor VIII (FVIII) to extended half-life (EHL) PEGylated turoctocog alfa pegol in patients with severe/moderate hemophilia A (HA) on prophylaxis, one year prior to and following the switch in a real-world setting. Methods: A single-center, comparative, observational, sequential, retrospective, multidisciplinary study was designed. The population pharmacokinetic parameters were estimated using the WAPPS-Hemo^® platform. The annualized bleeding rate (including total and joint bleeds), joint health (Hemophilia Joint Health Score), FVIII consumption, administration frequency, and treatment costs were analyzed. Results: Eight patients with severe (n = 7) or moderate (n = 1) HA on prophylaxis were included after switching to turoctocog alfa pegol. With this regimen, the median FVIII half-life was 16.8 (15.2–19.1) hours, the area under the curve (AUC) was 18,182 (12,879–21,214) IU·h/dL, and the incremental recovery was 2.2 IU/dL per (1.6–2.4) IU/kg. The patients required a median of 2.0 infusions per week (2.0–2.0), corresponding to a weekly consumption of 57.8 (54.2–61.1) IU/kg. Clinically, the prophylactic regimen was associated with fewer infusions per week, stable joint health, and a reduction in overall treatment costs. Conclusions: Prophylaxis with turoctocog alfa pegol provided the expected pharmacokinetic profile of an EHL-FVIII concentrate, enabled a lower infusion frequency, and was linked to a decreased treatment burden and cost while maintaining joint health. Full article

Background and Clinical Significance: Acquired hemophilia A (AHA) and acquired von Willebrand syndrome (AVWS) are rare bleeding disorders that do not often present concurrently. Here, we report a coexisting AHA and AVWS case due to underlying autoantibodies to factor VIII (FVIII) and von Willebrand factor (VWF). Case Presentation: A patient with gastrointestinal bleeding and prolonged aPTT was diagnosed with AHA and AVWS. The patient was started on immunosuppression with prednisone, cyclophosphamide, and intravenous immunoglobulin, alongside recombinant porcine FVIII replacement, susoctocog alfa. AVWS reduced the half-life of susoctocog alfa, requiring more frequent dosing and laboratory monitoring until AVWS resolved. The patient had two further relapses; the most recent was treated with Rituximab, following which remission has been maintained. Conclusions: Given the potential therapeutic implications, VWF testing should be considered as part of the diagnostic workup for AHA. Full article

Hemophilia, an X-linked recessive bleeding disorder, results from mutations in the F8 or F9 genes, leading to factor VIII (hemophilia A) or factor IX (hemophilia B) deficiency. While conventional treatment relies on regular factor replacement therapy, gene therapy has emerged as a promising alternative, offering the potential for sustained endogenous factor production after a single administration. This review provides an in-depth analysis of recent advances in gene therapy for both hemophilia A and B, with a focus on AAV-mediated liver-directed approaches and other approved modalities. Key limitations—such as vector immunogenicity, hepatic toxicity, waning transgene expression, and limited re-dosing capacity—are discussed. Additional gene delivery platforms, including lentiviral and retroviral vectors, genome editing techniques (e.g., CRISPR/Cas9), and non-viral systems like transposons and lipid nanoparticles, are also examined. Although gene therapy for hemophilia B demonstrates greater clinical durability, hemophilia A presents unique challenges due to factor VIII’s size, poor expression efficiency, and the need for higher vector doses. Future efforts will focus on overcoming immune barriers, improving delivery technologies, and developing approaches suitable for pediatric patients and individuals with pre-existing immunity. This review provides not only a descriptive overview but also a critical comparison of gene therapy approaches for hemophilia A and B. We emphasize that the durability of response is currently superior in hemophilia B, whereas hemophilia A still faces unique barriers, including declining FVIII expression and higher immunogenicity. By analyzing cross-platform challenges (AAV, lentiviral, CRISPR, and emerging LNPs), we highlight the most promising strategies for overcoming these limitations and provide a forward-looking perspective on the future of gene therapy. Full article

Background: Legg–Calvé–Perthes disease (LCPD) is a rare avascular osteonecrosis of the proximal femoral epiphysis and typically occurs during the childhood growth phase. LCPD is a complex illness of unknown origin, which is considered the main difficulty in the study of this disease. Various theories on LCPD etiology have been proposed; however, no consensus has been reached about its origin. Our research objective was to evaluate the polymorphisms FVL rs6025, FVIII rs5987061, FIX Malmö rs6048, PAI-1 rs1799889, eNOS rs17899983/rs2070744, IL-23R rs1569922/rs154655686/7539625, and TNF-α rs180062, and their relationship with LCPD. Methods: A blood sample was taken from each study participant. Complete blood count, coagulation times and factors, antithrombotic proteins, and homocysteine (Hcy) were determined using a coagulometric method. DNA was obtained and genotyped using real-time PCR with TaqMan probes. Genotypic and allelic distributions were analyzed using comparative analysis, the Hardy–Weinberg equilibrium, and OR. Results: This study included 46 children: 23 with LCPD (cases) and 23 without (controls). Statistically significant differences were found in Prothrombin Time, Factor V, and Factor IX activity, as well as Hcy concentration; these values suggest the presence of hypercoagulable states in patients, which can cause thrombotic events. On the other hand, significant differences were also found in the neutrophil–lymphocyte ratio and systemic immune-inflammation index, showing major inflammation states in the patient group. Moreover, statistically significant differences were found in the IL-23R rs1569922 polymorphism; it was found that carriers of the T/T and C/T genotypes have an increased risk of developing LCPD. Conclusions: Our results show greater hemostatic activity and inflammation in the group of patients included in this study, supporting various theories previously proposed. Therefore, we believe that LCPD is a multifactorial condition in which hemostatic, inflammatory, and genetic factors play a central and triggering role in the disease. Full article

Background/Objectives: The approach to physical activity in people with hemophilia (PwH) is still conditioned by many difficulties. Thus, a prospective observational pilot study has been carried out aiming to evaluate how an adequate and controlled training program can slow down the onset or evolution of arthropathy and improve musculoskeletal health and quality of life. Methods: Performed from April 2022 to April 2023, this study involved nine severe hemophilic A and B patients, aged > 18 years old, on regular prophylaxis with replacement products. Participants, without changing the usual prophylaxis schedule and maintaining a trough level of at least 20% FVIII/FIX before training, were involved in physical activity twice a week. Results: After 12 months, no increase in annual bleeding ratio (ABR) was observed, and baseline joint status (as assessable by HEAD US score, HJHS, and NRS) was maintained. Even if not statistically significant, a trend toward improvement in mean HEAD US score (15.55 vs. 13.11) and HJHS (14.4 vs. 11) from baseline was observed. Some of the physical tests performed showed a significant improvement at 6 months and 12 months from baseline (5 Rep Sit to Stand, Sit and Reach, and 6-minute Walking Test), meaning an improvement in leg strength, dorsal flexibility, and aerobic resistance. Conclusions: This is the first pilot study evaluating at 360 degrees the safety and impact of a controlled physical activity in PwH. No participant experienced bleedings or a worsening in joint status, but they experienced an improvement in articular functionality. Without changing the usual prophylaxis, scheduling training sessions according to individual pharmacokinetics turned out to be a safe and a cost-effective approach. Full article

Background and Objectives: Factor VIII (FVIII) and the von Willebrand factor (vWF) are key components of hemostatic balance. Disruption of the vWF-ADAMTS13 axis, characterized by elevated vWF and reduced ADAMTS13 activity has been implicated in thrombotic disorders, including COVID-19-asscoiated coagulopathy, where this imbalance correlates with disease severity and mortality. This study evaluated the relationship between plasma FVIII and vWF levels and the severity of coronary artery disease (CAD), as assessed by the SYNTAX score. Methods: We enrolled 82 patients with chronic coronary syndrome (CCS) and a positive treadmill test who underwent elective coronary angiography. Based on the SYNTAX score, patients were divided into three groups: Group I (≤22), Group II (23–32), and Group III (≥33). Results: FVIII levels varied significantly (Group I: 2.25 ± 0.75; Group III: 2.97 ± 0.95; p = 0.007), with an OR of 3.632 (95% CI: 1.116–11.826; p = 0.03). vWF levels differed significantly across SYNTAX groups (Group I: 1.16 ± 0.59; Group II: 1.52 ± 0.62; Group III: 1.49 ± 0.80; p = 0.040). vWF > 1.75 was more frequent in Groups II and III, with an odds ratio (OR) of 4.909 (95% CI: 1.429–16.864; p = 0.01) for Group III vs. Group I. Fibrinogen and C-reactive protein (CRP) were elevated in patients with SYNTAX scores ≥33. In multinomial logistic regression analysis, FVIII emerged as the sole independent predictor of CAD complexity (p = 0.004), while the vWF showed significance in pairwise comparison (Group II vs. Group I; OR = 3.433, p = 0.049). Conclusions: This study demonstrated significant differences in hemostatic and inflammatory biomarkers across SYNTAX score categories reflecting CAD severity in CCS patients. FVIII emerged as an independent predictor of CAD complexity, while the vWF demonstrated significant associations in specific subgroup comparisons. The observed vWF-ADAMTS13 axis dysregulation supports the rationale for investigating vWF-targeted therapeutics, including agents such as caplacizumab, in cardiovascular disease management. These findings require validation in larger studies. Full article

Atherosclerosis as a multifactorial disease remains the first cause of death worldwide. Current oral lipid-lowering drugs (especially statins) reduce low-density lipoprotein cholesterol (LDLC) levels in the blood, but their clinical efficacy seems to be partially attributed to pleiotropic effects on different pathophysiologic factors of atherosclerosis extending beyond lipid-lowering properties such as anti-inflammatory, antithrombotic and antioxidative features. Novel drugs that interfere with proprotein convertase subtilisin/kexin type 9 (PCSK9) axis of LDL-C receptors (LDLRs) degradation, from the group of monoclonal antibodies (e.g., alirocumab, evolocumab) or small interfering RNA (siRNA), e.g., inclisiran, are effective in reducing LDLC as well. However, data depicting their antithrombotic and antiplatelet activity are scarce, whereas prothrombotic properties of PCSK9 are widely described. Thus, we performed a study to assess the effects of inclisiran on subclinical prothrombotic [fibrinogen, coagulation factor VIII (FVIII), plasminogen activator inhibitor-1 (PAI-1)] and platelet activation markers (platelet factor-4 (PF-4), soluble p-selectin (sCD62P)). Ten patients at high cardiovascular risk with concomitant heterozygous familial hypercholesterolemia (HeFH)—study group 1, and fourteen patients at very high cardiovascular risk without concomitant HeFH—study group 2, were recruited for the study. Lipid profile, subclinical prothrombotic and platelet activation markers were assessed at the beginning and after 3 months of therapy with inclisiran. During therapy, statistically significant reductions in both study groups were seen in total cholesterol levels (study group 1: from 287.6 ± 94.2 to 215.2 ± 89.1 (mg/dL), p = 0.022; study group 2: from 211.7 ± 52.7 to 147.6 ± 55.4 (mg/dL), p < 0.001) and LDL-c (study group 1: from 180.8 ± 73.3 to 114.7 ± 71.5 (mg/dL), p = 0.031; study group 2: from 129.6 ± 46.8 to 63.4 ± 43.6 (mg/dL), p < 0.001). Lipid profile changes were associated with significant decrease in the concentration of FVIII in both groups (study group 1: from 33.3 ± 22 to 22 ± 14.5 (ng/mL), p = 0.006; study group 2: from 37 ±16.9 to 29.3 ±16.4 (ng/mL), p = 0.002) and fibrinogen, but only in study group 2 (from 51.4 (33.2–72.7) to 42.6 (31.3–57.2) (µg/mL), p = 0.035). Among platelet activation markers, a significant decrease in PF-4 in study group 2 was noted (from 286 (272–295.5) to 272 (268–281.5) (ng/mL), p = 0.047). However, there were no statistically significant changes in PAI-1 and sCD62P throughout the study. In our study, inclisiran appeared to be an effective lipid-lowering drug in patients at high cardiovascular risk. Moreover, it was shown that beyond lipid-lowering properties, the drug may also partially affect thrombogenesis and platelet activation. Full article

(1) Background: The presence of metastatic disease significantly increases the risk of venous thromboembolism (VTE) in breast cancer, particularly during chemotherapy. Although not categorized as a highly thrombogenic malignancy, the elevated global prevalence of this cancer places a substantial number of patients at risk of thrombosis, which cannot yet be accurately predicted by validated risk assessment models (RAMs), highlighting the need for a dedicated model. (2) Aim: This study aims to develop a RAM for VTE in newly diagnosed metastatic breast cancer patients enrolled in a prospective, observational, and multicenter study. (3) Methods: A cohort of 189 patients beginning antitumor therapy were enrolled and prospectively monitored for VTE and mortality. Blood samples collected at enrollment were tested for D-dimer, fibrinogen, FVIII, prothrombin fragment 1 + 2 (F1 + 2), and thrombin generation (TG). Competing risk analyses were performed to identify significant predictors. (4) Results: Within one year, the cumulative incidences of VTE and mortality were 7.0% and 12%, respectively. Univariable analysis identified high Ki-67, D-dimer, FVIII, fibrinogen, and TG levels, along with low hemoglobin levels, as independent predictors of VTE. Only Ki-67, fibrinogen, FVIII, and hemoglobin were retained as significant predictors in multivariable analysis. These variables were further examined by multiple linear regression, which revealed Ki-67 and fibrinogen as the most significant parameters. A continuous RAM was then developed based on Ki-67 and fibrinogen (c-statistics 0.78), categorizing patients into low-risk and high-risk groups for VTE (2% vs. 13%; SHR 3.6, p = 0.018). This stratification could not be achieved using currently validated models for VTE risk. (5) Conclusions: We developed an accurate RAM for VTE that enables the identification of metastatic breast cancer patients at high risk for VTE, which supports clinicians in personalized thromboprophylaxis strategies if externally validated. Full article

Background and Clinical Significance: Hemophilia A presents a considerable challenge in cardiac surgery due to the elevated risk of perioperative bleeding, particularly during procedures involving cardiopulmonary bypass. Standard management typically involves standard half-life (SHL) factor VIII (FVIII) concentrates, which require frequent dosing. Extended half-life (EHL) FVIII products offer theoretical advantages, including prolonged action and reduced infusion frequency, but their use in cardiac surgery remains largely undocumented. Case Presentation: We report the case of a 73-year-old male with mild Hemophilia A who underwent successful aortic valve replacement using a 25 mm Carpentier-Edwards Magna Ease biological prosthesis. The patient was managed perioperatively with an anti-hemorrhagic protocol based on EHL recombinant FVIII. The surgery and postoperative course were uneventful, with no bleeding complications or need for transfusion. Conclusions: This case illustrates the potential role of EHL FVIII in safely managing hemophilic patients undergoing major cardiac surgery. Given the lack of existing reports in the literature, further studies are warranted to evaluate the efficacy and safety of EHL FVIII in this setting and to potentially optimize perioperative care protocols for this patient population. Full article