Hemophilia is a rare lifelong condition which can be potentially life-threatening. Parents bare a significant responsibility for delivery of medical care because the treatment for hemophilia begins early in life for children within the home setting. As a result, parents frequently exhibit a heightened level of stress, anxiety, and subsequent trauma around the acceptance of the illness and the administration of medication management. To address the multifaceted nature of chronic illness for patients and their families, the ideal treatment utilizes a multidisciplinary team. Our proposed 3P Patient Parent Power Program aims to standardize care for families with patients of hemophilia using a tiered approach of psychosocial support. The necessary level of support will be provided to parents in order for them to successfully provide in-home prophylactic factor treatment. The goal of the program is to reduce parental stress and anxiety related to this chronic illness and increase feelings of empowerment for the parent and child.
Objective:
To investigate the prevalence of comorbidities among adults with hemophilia in the Hemophilia Utilization Group Studies (HUGS)
Methods:
Standardized interviews were conducted for two prospective cohort studies HUGS- Va (hemophilia A) and HUGS-Vb (hemophilia B) at six and ten US Hemophilia Treatment Centers, respectively, between 2005 and 2011. Clinical records were reviewed. Information captured included self-reported comorbidities, sociodemographics, treatment patterns and other clinical characteristics. Overweight and obesity were defined as body mass index (BMI) 25-29 kg/m2 and BMI ≥30 kg/m2, respectively. The prevalence of comorbidities was calculated. The association of comorbidities with hemophilic severity, age and type of hemophilia were assessed using appropriate statistical methods for categorical or continuous variables.
Summary:
The analyses included a total of 213 adults (HUGS-Va: n=147, HUGS-Vb: n=66) aged 20 to 65 years (mean±standard deviation: 36.6±12.9). Approximately, 64% of hemophilia A and 44% of hemophilia B individuals had severe hemophilia. The five most prevalent self-reported comorbidities were liver disease/hepatitis (66%), overweight/obesity (60%), arthritis (51%), human immunodeficiency virus infection/acquired immunodeficiency syndrome (HIV/AIDS) (24%), and hypertension (23%). The individuals in the hemophilia A sample were more likely to report liver disease/hepatitis (71% vs. 53%) and HIV/AIDS (30% vs. 9%) than those in the hemophilia B sample (all p<0.009). The prevalence of overweight/obesity (59% vs. 60%), arthritis (55% vs. 42%), and hypertension (22% vs. 24%) were not significantly different between hemophilia A and hemophilia B samples (all p>0.05). Prevalence of comorbidities was greater among individuals with severe than mild/moderate hemophilia for most conditions: liver disease/hepatitis (79% vs. 48%), arthritis (61% vs. 38%), HIV/AIDS (37% vs. 6%), and stroke/brain haemorrhage (11% vs. 2%) (all p<0.02), the exception being overweight/obesity (52% vs. 70%, p=0.007). The individuals with hemophilia A had a significantly greater number of comorbidities than those with hemophilia B (mean±standard deviation: 2.5±1.9 vs. 1.0±1.1; p<0.0001); 85% of the hemophilia A sample reported having more than one comorbidity compared to 61% of those with hemophilia B (p<0.0001). The number of comorbidities increased significantly with advancing age (p<0.0001).
Conclusions:
As one of the largest prospective studies of persons with hemophilia, the HUGS sample is representative of the US hemophilia A and B populations. Except for overweight/obesity, the most prevalent comorbidities reported in HUGS related to their hemophilia complications, and were significantly associated with hemophilic severity. As the life expectancy of persons with hemophilia increases, the need for studies focusing on the health care needs of individuals with hemophilia and comorbid conditions will increase.
Objectives:
Factor VIII (FVIII) prophylaxis regimens for severe hemophilia A that allow more flexible dosing than the standard 3-times-weekly regimen while maintaining efficacy may improve adherence. This analysis compared the clinical efficacy of once- or twice-weekly versus ≥3-times-weekly prophylaxis dosing of Bayer’s sucrose-formulated recombinant FVIII (rFVIII-FS) in patients with severe hemophilia A.
Methods:
Data from 3 postmarketing studies were pooled. Patients with severe hemophilia A and no history of inhibitors who were receiving ≥1 prophylaxis infusion/wk of rFVIII-FS for ≥80% of a prophylaxis observation period (≥5 months) were included. Patients were categorized based on age (<18 and ≥18 years) and physician-assigned treatment regimens of 1–2 prophylaxis injections/wk (n=63) or ≥3 prophylaxis injections/wk (n=76). Descriptive statistics were determined for annualized bleeding rates (ABRs) by dosing group and age subgroups.
Summary:
Median (quartile 1; quartile 3) ABR for all bleeds was 2.0 (0; 4.0) in the group receiving 1–2 prophylaxis injections/wk and 3.9 (1.5; 9.3) in the group with ≥3 prophylaxis injections/wk. Similarly, median ABRs for joint, spontaneous, and trauma-related bleeds were numerically lower in the group receiving 1–2 prophylaxis injections/wk. The trend toward lower ABRs in the group with 1–2 prophylaxis injections/wk was observed in both age subgroups, although ABRs were somewhat higher in patients ≥18 vs <18 years. Zero annualized bleeds were reported by 30% and 7% of patients in the groups with 1–2 prophylaxis injections/wk and ≥3 prophylaxis injections/wk, respectively.
Conclusions:
These data demonstrate that bleeding control can be achieved in some patients with severe hemophilia A using a <3-times-weekly prophylaxis dosing regimen and that physicians’ judgment based on bleeding phenotype can successfully direct the frequency of prophylactic dosing.
Objective:
Baxter has developed BAX 855, a PEGylated form of Baxter’s recombinant full length FVIII (rFVIII) product based on the ADVATETM manufacturing process. Here we describe it ́s manufacturing and structural and functional characterization.
Methods:
A rFVIII intermediate of the ADVATETM manufacturing process is the starting material for the conjugation process for preparing BAX 855 by proprietary PEGylation technology from Nektar Therapeutics. Similar technology has been successfully employed for marketed and licensed PEGylated drug products and drugs in clinical use. The manufacturing process for BAX 855 comprises several steps, including controlled PEGylation followed by cation exchange chromatography. Final formulation uses the same excipients as ADVATETM. BAX 855 was characterized by a number of analytical methods, focusing on the elucidation of the primary structure, posttranslational modifications, PEGylation site distribution and three- dimensional structure. The overall hemostatic potency of BAX 855 in FVIII-deficient plasma was assessed by conventional FVIII 1-stage clotting and chromogenic assays and with a thrombin generation assay. The tenase cofactor activity of FVIII was determined by measuring the kinetics of FXa generation. Binding of BAX 855 in comparison to ADVATETM was determined to its ligands VWF and low-density lipoprotein-receptor-related protein (LRP).
Summary and Conclusions:
BAX 855 is a full-length rFVIII with extended half-life. PK studies in different animal species and humans with hemophilia A display longer survival of BAX 855 compared to ADVATETM. The product is based on the original, native FVIII protein utilized in the production of ADVATETM. Our analyses show that BAX 855 can be manufactured reproducibly without changes to the protein structure characteristic for a fully functional full-length rFVIII molecule. The process is suited to manufacture BAX 855 in large scale and showed a good batch to batch consistency, ensuring an equivalent product quality for each batch. BAX 855 has a specific activity similar to that of rFVIII in ADVATETM and PEGylation degrees in the range of 2 to 3 mol PEG / mol rFVIII. SDS-PAGE and Western blot analysis of BAX 855 confirm PEGylation and demonstrate an increase in the molecular weight of the various FVIII domains.
In comparison to ADVATETM the functional properties of BAX 855 were fully retained except for binding to LRP, indicating that PEGylation did not have an impact on the functional properties of rFVIII. The latter might explain why BAX 855 shows prolonged survival in the circulation of hemophilic species and patients with hemophilia A than ADVATETM.
