The Association of Aging With Von Willebrand Factor Levels and Bleeding Risk in Type 1 Von Willebrand Disease.

Little is known about aging in von Willebrand disease (VWD). It is uncertain whether VWD patients experience an age-related increase in von Willebrand factor (VWF) levels, and if so, it is unknown whether normalization of VWF levels with aging ameliorates bleeding risk. We aimed to determine the association of age with VWF levels and bleeding risk in patients with type 1 VWD. This is a retrospective chart review of patients with type 1 VWD presenting to the Hemophilia Clinic of Western Pennsylvania for regularly scheduled clinic visits. Data collected included VWF antigen level and condensed molecular and clinical markers for the diagnosis and management of Type 1 (MCMDM-1) VWD bleeding assessment tool (BAT) bleeding score based on bleeding symptoms during the previous 3 years. Thirty-nine patients participated in the study, and 32 were female. The average age of participants was 41.8 ± 18.0 years. The mean VWF antigen level was 0.83 ± 0.37 IU/mL, and the mean bleeding score was 2.51 ± 2.90. The bleeding score was inversely associated with age, ß = -0.080 (SE = 0.023), P < .01. There was a nonsignificant association between VWF antigen levels and age. To our knowledge, this is the first report showing an association between aging and decreased bleeding symptoms in patients with type 1 VWD. Determining whether or not bleeding risk is reduced in older patients with type 1 VWD is essential for optimal clinical management. Moreover, VWF concentrate is costly, and unwarranted use represents a significant waste of health-care dollars. These findings warrant further investigation.

Cost analysis of plasma-derived factor VIII/von Willebrand factor versus recombinant factor VIII for treatment of previously untreated patients with severe hemophilia A in the United States.

BACKGROUND: Inhibitor development to factor VIII (FVIII) hemophilia therapy results in increased complications and substantial economic costs. The SIPPET study, the first randomized controlled trial to compare the immunogenicity of plasma-derived FVIII (pdFVIII)/von Willebrand factor (VWF) and recombinant-DNA-derived FVIII (rFVIII), demonstrated higher inhibitor rates in previously untreated patients (PUPs) treated with rFVIII than in PUPs treated with pdFVIII/VWF. OBJECTIVE: To quantify the economic impact of treating PUPs with pdFVIII/VWF vs rFVIII. METHODS: An Excel-based clinical and economic model was developed from a US healthcare payer perspective and run over a 5-year period. The analysis utilized a cohort approach to model patient treatment and outcomes over a monthly cycle to quantify differences in costs of FVIII, bypassing agents, and hospitalizations for serious bleeds. Rates of high-titer inhibitor development were obtained from the SIPPET study. Patients developing high-titer inhibitors were treated with immune tolerance induction (ITI). Patients who developed low-titer inhibitors and those who did not develop inhibitors continued their usual FVIII treatment. Patients who were successfully treated with ITI returned to FVIII treatment, while unsuccessfully treated patients received bypassing agents. Total costs per treated patient were estimated and a one-way sensitivity analysis was conducted to quantify the impact of parameter uncertainty on the model outcomes. RESULTS: Total cumulative costs per patient over 5 years were $834,621 for pdFVIII/VWF patients and $1,237,163 for rFVIII patients, representing a total saving of $402,542 per patient over the 5-year period, for an average annual saving of $80,508 per patient. CONCLUSIONS: Based on data from the SIPPET study, this analysis found that initiating FVIII treatment in severe hemophilia A PUPs with pdFVIII/VWF has the potential to offer substantial cost savings to healthcare payers, amounting to a one-third reduction in costs.

Beriate® P in the treatment of patients with haemophilia A: results of a long-term pharmacovigilance study.

BACKGROUND: The German Beriate(®) P pharmacovigilance study started in 2003 and is planned to run until December 2013. MATERIALS AND METHODS: This analysis included data from 84 haemophilia A patients treated with the high-purity, plasma-derived coagulation factor VIII concentrate Beriate(®) P. Prior to study start, 69 of the 80 patients for whom data were available had received previous treatment with Beriate(®) P (mean treatment period 7.1 ± 5.4 years). The mean study duration from the start of pharmacovigilance was 43.3 ± 30.3 months (median 43.5 months; range 0-101.9months). The most common treatment at the last visit was prophylaxis (65.7% of patients), which was most commonly administered at a frequency of three infusions/week in 47.3% of patients. RESULTS: Most patients experienced up to six minor bleeds/year. For 1,311 bleeding episodes, a median of one infusion/bleed was administered (mean 2.8 ± 4.7; range 0-83). The clinical response to Beriate(®) P was rated "excellent"/"good" in 94% of 32 visits of patients with major bleeding. The clinical response for patients with minor bleeding was rated "excellent"/"good" in 98.5% of 377 visits. One clinically relevant inhibitor in a previously untreated patient was documented during the study course. There were no reports of virus transmissions suspected to be caused by Beriate(®) P prior to the study start or during the study. CONCLUSIONS: These findings confirm the excellent efficacy, safety, and tolerability of Beriate(®) P in the treatment of a wide spectrum of previously untreated patients up to adult patients with haemophilia A.