Pharmacokinetic Parameter Driven Outcomes Model Predicts a Reduction in Bleeding Events Associated with BAY 81-8973 Versus Antihemophilic Factor (Recombinant) Plasma/Albumin- Free Method in a Chinese Healthcare Setting

Background: Long-term prophylactic therapy is considered the standard of care for hemophilia A patients. This study models the long-term clinical and cost outcomes of two factor VIII (FVIII) products using a pharmacokinetic (PK) simulation model in a Chinese population. Methods: Head-to-head PK profile data of BAY 81-8973 (KOVALTRY®) and antihemophilic factor (recombinant) plasma/albumin-free method (rAHF-PFM, ADVATE®) were applied to a two-state (alive and dead) Markov model to simulate blood FVIII concentrations at a steady state in prophylactically-treated patients with hemophilia A. Worsening of the Pettersson score was simulated and decline was associated with the probability of having orthopaedic surgery. The only difference between the compounds was FVIII concentration at a given time; each subject was treated with 25 IU/kg every 3 days. The model used a lifetime horizon, with cycle lengths of 1 year. Results: Cumulative bleeding events, joint bleeding events, and major bleeding events were reduced by 19.3%, 9.3% and 19.3%, respectively for BAY 81-8973 compared to rAHF-PFM. Hospitalizations and hospitalization days were also reduced by 19.3% for BAY 81-8973 compared to rAHF-PFM. BAY 81-8973 resulted in both cost savings and a gain in quality adjusted life years (QALYs) compared to rAHF-PFM. Conclusion: Based on modeled head-to-head comparisons, differences in PK-properties between BAY 81-8973 and rAHF-PFM result in a reduced number of bleeding events, leading to reduced costs and increased quality of life for BAY 81-8973. These results should be used to inform clinical practice in China when caring for patients with severe hemophilia A.

Phase 4 Safety and Efficacy Study of Antihemophilic Factor (Recombinant) in Previously Treated Chinese Patients With Severe/Moderately Severe Hemophilia A

Antihemophilic factor (recombinant) (rAHF; ADVATE®; Baxalta US Inc., a Takeda company, Lexington, MA, USA) is indicated for the treatment and prevention of bleeding in patients with hemophilia A. We aimed to assess the safety and efficacy of standard prophylaxis versus on-demand treatment with rAHF in previously treated Chinese patients with severe/moderately severe hemophilia A. This open-label, sequential, interventional, postapproval study (NCT02170402) conducted in China included patients of any age with hemophilia A with factor VIII (FVIII) level ≤2%. Patients received 6 months’ on-demand rAHF then 6 months’ rAHF prophylaxis (20-40 IU/kg every 48 ± 6 hours). The primary objective was percentage reduction in annualized bleeding rate (ABR) in the per-protocol analysis set (PPAS); secondary objectives included ABR by bleeding subtype, hemostatic efficacy, immunogenicity, and safety. Of 72 patients who received ≥1 rAHF dose, 61 were included in the PPAS. Total ABR was lower during prophylaxis (mean 2.5, 95% CI 1.5-3.7; median 0) versus on-demand treatment (mean 58.3, 95% CI 52.5-64.7; median 53.9), representing a 95.9% risk reduction. Similar findings in favor of prophylaxis were observed for all types of bleeding event by cause and location. rAHF hemostatic efficacy was rated as “excellent”/“good” in 96.1% of treated bleeding events. Transient FVIII inhibitors (0.6-1.7 BU) in 4 patients resolved before study end; no unexpected safety issues were observed. rAHF prophylaxis in this study of previously treated Chinese patients with severe/moderately severe hemophilia A resulted in a clear reduction in bleeding events versus rAHF on-demand treatment, with no change in safety profile.

Mechanisms of Bone Remodeling Disorder in Hemophilia

Hemophilia is caused by a lack of antihemophilic factor(s), for example, factor VIII (FVIII; hemophilia A) and factor IX (FIX; hemophilia B). Low bone mass is widely reported in epidemiological studies of hemophilia, and patients with hemophilia are at an increased risk of fracture. The detailed etiology of bone homeostasis imbalance in hemophilia is unclear. Clinical and experimental studies show that FVIII and FIX are involved in bone remodeling. However, it is likely that antihemophilic factors affect bone biology through thrombin pathways rather than via their own intrinsic properties. In addition, among patients with hemophilia, there are pathophysiological processes in several systems that might contribute to bone loss. This review summarizes studies on the association between hemophilia and bone remodeling, and might shed light on the challenges facing the care and prevention of osteoporosis and fracture in patients with hemophilia.

Effectiveness and Safety Outcomes in Patients with Hemophilia a Receiving Antihemophilic Factor (Recombinant) for at Least 5 Years in a Real-World Setting: 6-Year Interim Analysis of the Ahead International and German Studies

Introduction: Long-term effectiveness and safety data in patients treated in routine clinical practice settings can be captured from real-world studies. The international (INT) and German (GER) Antihemophilic factor (recombinant; rAHF) Hemophilia A (HA) outcome Database (AHEAD) studies assess long-term effectiveness and safety outcomes in patients with moderate HA (factor VIII level 1-5%) or severe HA (factor VIII <1%) receiving rAHF (ADVATE®; Baxalta US Inc., a Takeda company, Lexington, MA, USA) in routine clinical practice. Methods: These are non-interventional, prospective, long-term, multicenter studies (INT: NCT02078427; GER: DRKS 00000556). Key outcomes include Gilbert scores (primary endpoint; pain scored 0-3; bleeding scored 0-3, and physical exam scored 0-12), annualized bleeding rates (ABRs) by disease severity, and adverse events (AEs). Findings reported here are from the 6-year interim analysis (data cut-off: July 15, 2019), and focus on patients who have received rAHF prophylaxis or on-demand (OD) treatment for ≥5 years in the studies. All data are reported for the safety analysis set (SAS), which comprised patients who passed screening and were assigned to a treatment group or regimen in the INT study, or were enrolled and have received ≥1 dose of rAHF since study enrollment in the GER study. Results: At the time of analysis, the INT study SAS comprised 707 patients, 156 of whom had received ≥5 years of rAHF treatment during the study. The GER study SAS comprised 382 patients, 231 of whom had received ≥5 years of rAHF treatment. Average Gilbert scores (all joints) were consistently low (years 1-6: median 0-1.0; mean 0-1.3) for both children aged 2 to <12 years and adolescents aged 12 to <18 years receiving rAHF prophylaxis within both studies. In the INT study, average Gilbert scores were lower with prophylaxis than with OD therapy in adults (aged ≥18 years) throughout the observation period (years 1-6: median: 0.9-1.4 [n=8-25] vs 1.4-6.3 [n=2-8], respectively; mean: 1.4-2.2 vs 2.1-6.3; respectively); significant differences (P<0.05) between mean values were observed for years 3, 4, and 6. In the GER study, average Gilbert scores were slightly higher with prophylaxis than with OD in adults (years 1-6: median: 0.7-2.2 [n=12-37] vs 0.3-1.4 [n=2-15], respectively; mean: 1.0-2.7 vs 0.5-2.2, respectively; P-values not available). In the INT study, ABRs were consistently lower in patients receiving rAHF prophylaxis than in those receiving rAHF OD, irrespective of disease severity (Table). A similar trend was observed in the GER study in patients with severe HA, whereas ABRs were similar for both treatment regimens in patients with moderate HA. In both studies, greater proportions of patients with moderate or severe HA receiving rAHF prophylaxis had 0 bleeds than those receiving rAHF OD (Table). In the INT study, 842 AEs were reported in 116/156 (74.4%) patients, including 2 treatment-related serious AEs in 2 (1.3%) patients. In the GER study, 1321 AEs were reported in 197/231 (85.3%) patients, including 29 treatment-related serious AEs in 14 (6.1%) patients. Conclusions: These findings in patients receiving rAHF for ≥5 years in a real-world setting corroborate previous data on the long-term efficacy and tolerability of rAHF in patients with moderate or severe HA. rAHF demonstrated effectiveness in maintaining joint health (as measured by Gilbert scores) in adult patients. Table Disclosures Tsakiris: Roche: Research Funding; Shire, a Takeda company: Research Funding; Sobi: Research Funding; Bayer: Research Funding; CSL Behring: Research Funding; Novo Nordisk: Research Funding; Pfizer: Research Funding; Octapharma: Research Funding. Oldenburg:Sobi: Consultancy, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau; Biotest: Consultancy, Research Funding, Speakers Bureau; CSL Behring: Consultancy, Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Octapharma: Consultancy, Research Funding, Speakers Bureau; Pfizer: Consultancy, Research Funding, Speakers Bureau; Shire, a Takeda company: Consultancy, Research Funding, Speakers Bureau; Biogen: Consultancy, Speakers Bureau; Chugai: Consultancy, Speakers Bureau; Grifols: Consultancy, Speakers Bureau; Roche: Consultancy, Speakers Bureau. Klamroth:Pfizer: Consultancy, Research Funding, Speakers Bureau; Biotest: Speakers Bureau; Grifols: Speakers Bureau; Takeda/Shire: Consultancy, Research Funding, Speakers Bureau; Octapharma: Consultancy, Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Biomarin: Consultancy, Research Funding, Speakers Bureau; CSL Behring: Research Funding, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Sobi: Consultancy, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau. Guillet:CSL Behring: Research Funding, Speakers Bureau; Octapharma: Research Funding; Bayer: Consultancy; Novo Nordisk: Consultancy, Speakers Bureau; Shire, a Takeda company: Consultancy, Speakers Bureau; Roche-Chugai: Consultancy, Speakers Bureau. Khair:Shire, a Takeda company: Consultancy, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Pfizer: Research Funding, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Sobi: Consultancy, Research Funding, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Baxalta/Shire, Takeda companies: Research Funding. Huth-Kühne:Bayer: Consultancy; CSL Behring: Consultancy; Shire, a Takeda company: Consultancy; Sobi: Consultancy. Kurnik:Sobi: Consultancy, Research Funding; Biotest: Consultancy, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau; CSL Behring: Consultancy, Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Pfizer: Research Funding; Roche: Consultancy, Research Funding, Speakers Bureau; Shire, a Takeda company: Consultancy, Research Funding, Speakers Bureau. Regensburger:Takeda Pharma Vertrieb GmbH & Co. KG: Current Employment, Current equity holder in publicly-traded company. Botha:Takeda Pharmaceutical International AG: Current Employment, Current equity holder in publicly-traded company. Fernandez:Takeda Pharmaceutical International AG: Current Employment, Current equity holder in publicly-traded company. Tang:Takeda Pharmaceutical International AG: Current Employment, Current equity holder in publicly-traded company. Ozelo:Pfizer: Consultancy, Research Funding; Shire/Takeda: Consultancy, Research Funding, Speakers Bureau; Roche: Consultancy, Research Funding, Speakers Bureau; Bioverativ/Sanofi: Consultancy, Research Funding; BioMarin: Consultancy, Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau.