Pharmacokinetics, clot strength and safety of a new fibrinogen concentrate: randomized comparison with active control in congenital fibrinogen deficiency
Journal of Thrombosis and Haemostasis : Jth. 2017;16((2):):253-261
BACKGROUND Human fibrinogen concentrate (HFC) corrects fibrinogen deficiency in congenital a-/hypofibrinogenaemia. OBJECTIVES To assess pharmacokinetics (PK), effects on thromboelastometry maximum clot firmness (MCF), and safety of a new double virus-inactivated/eliminated, highly purified HFC vs. active control. PATIENTS/METHODS In this multinational, randomized, phase II, open-label, crossover study in 22 congenital afibrinogenaemia patients ≥12 years, 70 mg kg(-1) of new HFC (FIBRYGA, Octapharma AG) or control (Haemocomplettan((R)) P/RiaSTAP() , CSL Behring GmbH) were administered, followed by crossover to the other concentrate. Fibrinogen activity, PK and MCF in plasma were assessed. RESULTS The concentrates were not bioequivalent for the primary endpoint, AUCnorm (mean ratio 1.196; 90% CI: 1.117, 1.281). Remaining PK parameters (Cmaxnorm , IVR, t1/2 , MRT) reflected bioequivalence between concentrates, except for clearance (mean ratio 0.836; 90% CI: 0.781, 0.895) and Vss (mean ratio 0.886; 90% CI: 0.791, 0.994). Mean AUCnorm was significantly larger for the new HFC (1.62 +/- 0.45 vs. 1.38 +/- 0.47 h kg g L(-1) mg(-1) , p=0.0001) and mean clearance was significantly slower (0.665 +/- 0.197 vs. 0.804 +/- 0.255 mL h(-1) kg(-1) , p=0.0002). Mean MCF increased from 0 mm to 9.68 mm (new HFC) and 10.00 mm (control) 1-hour post-infusion (mean difference -0.32 mm, 95% CI -1.70, 1.07, n.s.). No deaths, thromboses, viral seroconversions or serious related adverse events occurred. CONCLUSIONS Bioequivalence was not demonstrated for AUCnorm , clearance and Vss. Larger AUCnorm and slower clearance were observed for the new HFC. Remaining pharmacokinetic parameters reflected bioequivalence to control. Safety profiles and increases in clot strength were comparable between concentrates. This article is protected by copyright. All rights reserved.
A randomized trial of factor VIII and neutralizing antibodies in hemophilia A
The New England Journal of Medicine. 2016;374((21)):2054-64.
BACKGROUND The development of neutralizing anti-factor VIII alloantibodies (inhibitors) in patients with severe hemophilia A may depend on the concentrate used for replacement therapy. METHODS We conducted a randomized trial to assess the incidence of factor VIII inhibitors among patients treated with plasma-derived factor VIII containing von Willebrand factor or recombinant factor VIII. Patients who met the eligibility criteria (male sex, age <6 years, severe hemophilia A, and no previous treatment with any factor VIII concentrate or only minimal treatment with blood components) were included from 42 sites. RESULTS Of 303 patients screened, 264 underwent randomization and 251 were analyzed. Inhibitors developed in 76 patients, 50 of whom had high-titer inhibitors (≥5 Bethesda units). Inhibitors developed in 29 of the 125 patients treated with plasma-derived factor VIII (20 patients had high-titer inhibitors) and in 47 of the 126 patients treated with recombinant factor VIII (30 patients had high-titer inhibitors). The cumulative incidence of all inhibitors was 26.8% (95% confidence interval [CI], 18.4 to 35.2) with plasma-derived factor VIII and 44.5% (95% CI, 34.7 to 54.3) with recombinant factor VIII; the cumulative incidence of high-titer inhibitors was 18.6% (95% CI, 11.2 to 26.0) and 28.4% (95% CI, 19.6 to 37.2), respectively. In Cox regression models for the primary end point of all inhibitors, recombinant factor VIII was associated with an 87% higher incidence than plasma-derived factor VIII (hazard ratio, 1.87; 95% CI, 1.17 to 2.96). This association did not change in multivariable analysis. For high-titer inhibitors, the hazard ratio was 1.69 (95% CI, 0.96 to 2.98). When the analysis was restricted to recombinant factor VIII products other than second-generation full-length recombinant factor VIII, effect estimates remained similar for all inhibitors (hazard ratio, 1.98; 95% CI, 0.99 to 3.97) and high-titer inhibitors (hazard ratio, 2.59; 95% CI, 1.11 to 6.00). CONCLUSIONS Patients treated with plasma-derived factor VIII containing von Willebrand factor had a lower incidence of inhibitors than those treated with recombinant factor VIII. (Funded by the Angelo Bianchi Bonomi Foundation and others; ClinicalTrials.gov number, NCT01064284; EudraCT number, 2009-011186-88.).
Randomized, controlled, parallel-group trial of routine prophylaxis vs. on-demand treatment with sucrose-formulated recombinant factor VIII in adults with severe hemophilia A (SPINART)
Journal of Thrombosis & Haemostasis. 2013;11((6):):1119-27.
BACKGROUND The benefits of routine prophylaxis vs. on-demand treatment with factor VIII products have not been evaluated in controlled clinical trials in older patients with hemophilia A. OBJECTIVES To report results from a preplanned analysis of data from the first year of the 3-year SPINART study, which compares routine prophylaxis with on-demand treatment with sucrose-formulated recombinant FVIII (rFVIII-FS). PATIENTS/METHODS SPINART is an open-label, randomized, controlled, parallel-group, multinational trial. Males aged 12-50 years with severe hemophilia A, > 150 days of exposure to FVIII, no FVIII inhibitors, no prophylaxis for > 12 consecutive months in the past 5 years and 6-24 bleeding episodes in the preceding 6 months were randomized 1 : 1 to rFVIII-FS prophylaxis (25 IU kg(-1) , three times weekly) or on-demand treatment. The primary efficacy endpoint, number of total bleeding episodes in the intent-to-treat population, was analyzed after the last patient had completed 1 year of follow-up. A negative binomial model was used for the primary endpoint analysis; analysis of variance was used for confirmatory analysis of annualized bleeding rates. RESULTS Eighty-four patients were enrolled and analyzed (n = 42 per group; mean age, 30.6 years; median treatment duration, 1.7 years). The median number of total bleeding episodes and total bleeding episodes per year were significantly lower with prophylaxis than with on-demand treatment (total, 0 vs. 54.5; total per year, 0 vs. 27.9; both P < 0.0001). No treatment-related adverse events occurred, and no patients developed FVIII inhibitors. CONCLUSIONS Routine prophylaxis with rFVIII-FS leads to a significant reduction in bleeding as compared with on-demand treatment. Adverse events were consistent with the established rFVIII-FS safety profile. 2013 International Society on Thrombosis and Haemostasis.
Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia
The New England Journal of Medicine. 2007;357((6):):535-44.
BACKGROUND Effective ways to prevent arthropathy in severe hemophilia are unknown. METHODS We randomly assigned young boys with severe hemophilia A to regular infusions of recombinant factor VIII (prophylaxis) or to an enhanced episodic infusion schedule of at least three doses totaling a minimum of 80 IU of factor VIII per kilogram of body weight at the time of a joint hemorrhage. The primary outcome was the incidence of bone or cartilage damage as detected in index joints (ankles, knees, and elbows) by radiography or magnetic resonance imaging (MRI). RESULTS Sixty-five boys younger than 30 months of age were randomly assigned to prophylaxis (32 boys) or enhanced episodic therapy (33 boys). When the boys reached 6 years of age, 93% of those in the prophylaxis group and 55% of those in the episodic-therapy group were considered to have normal index-joint structure on MRI (P=0. 006). The relative risk of MRI-detected joint damage with episodic therapy as compared with prophylaxis was 6. 1 (95% confidence interval, 1. 5 to 24. 4). The mean annual numbers of joint and total hemorrhages were higher at study exit in the episodic-therapy group than in the prophylaxis group (P<0. 001 for both comparisons). High titers of inhibitors of factor VIII developed in two boys who received prophylaxis; three boys in the episodic-therapy group had a life-threatening hemorrhage. Hospitalizations and infections associated with central-catheter placement did not differ significantly between the two groups. CONCLUSIONS Prophylaxis with recombinant factor VIII can prevent joint damage and decrease the frequency of joint and other hemorrhages in young boys with severe hemophilia A. (ClinicalTrials. gov number, NCT00207597 [ClinicalTrials. gov]. ).