Management of Intracranial Hemorrhage in Patients with a Left Ventricular Assist Device: A Systematic Review and Meta-Analysis

BACKGROUND

Intracranial hemorrhage (ICH) has been reported to occur in up to 23% of patients with left ventricular assist devices (LVADs). Currently, limited data exists to guide neurosurgical management strategies to optimize outcomes in patients with an LVAD who develop ICH.

METHODS

A systematic review and meta-analysis of the literature was performed to evaluate the mortality rate in these patients following medical and/or surgical management and to evaluate antithrombotic reversal and resumption strategies after hemorrhage.

RESULTS

17 studies reporting on 3869 LVAD patients and 545 intracranial hemorrhages spanning investigative periods from 1996 to 2019 were included. The rate of ICH in LVAD patients was 10.6% (411/3869) with 58.6% (231/394) being intraparenchymal hemorrhage (IPH), 23.6% (93/394) subarachnoid hemorrhage (SAH), and 15.5% (61/394) subdural hemorrhage (SDH). Total mortality rates for surgical management 65.6% (40/61) differed from medical management at 45.2% (109/241). There was an increased relative risk of mortality (RR=1.45, 95% CI: 1.10-1.91, p = 0.01) for ICH patients undergoing surgical intervention. The hemorrhage subtype most frequently managed with anticoagulation reversal was IPH 81.8% (63/77), followed by SDH 52.2% (12/23), and SAH 39.1% (18/46). Mean number of days until antithrombotic resumption ranged from 6 to 10.5 days.

CONCLUSION

Outcomes remain poor, specifically for those undergoing surgery. As experience with this population increases, prospective studies are warranted to contribute to management and prognostication .

Computer-based simulation to reduce EHR-related chemotherapy ordering errors

BACKGROUND

The electronic health record (EHR) is a contributor to serious patient harm occurring within a sociotechnical system. Chemotherapy ordering is a high-risk task due to the complex nature of ordering workflows and potential detrimental effects if wrong chemotherapeutic doses are administered. Many chemotherapy ordering errors cannot be mitigated through systems-based changes due to the limited extent to which individual institutions are able to customize proprietary EHR software. We hypothesized that simulation-based training could improve providers' ability to identify and mitigate common chemotherapy ordering errors.

METHODS

Pediatric hematology/oncology providers voluntarily participated in simulations using an EHR testing ("Playground") environment. The number of safety risks identified and mitigated by each provider at baseline was recorded. Risks were reviewed one-on-one after initial simulations and at a group "lunch-and-learn" session. At three-month follow-up, repeat simulations assessed for improvements in error identification and mitigation, and providers were surveyed about prevention of real-life safety events.

RESULTS

The 8 participating providers identified and mitigated an average of 5.5 out of 10 safety risks during the initial simulation, compared 7.4 safety risks at the follow up simulation (p=0.030). Two of the providers (25%) reported preventing at least one real-world patient safety event in the clinical setting as a result of the initial training session.

CONCLUSIONS

Simulation-based training may reduce providers' susceptibility to chemotherapy ordering safety vulnerabilities within the EHR. This approach may be used when systems-based EHR improvements are not feasible due to limited ability to customize local instances of proprietary EHR software.

Efficacy of emicizumab prophylaxis versus factor VIII prophylaxis for treatment of hemophilia A without inhibitors: network meta-analysis and sub-group analyses of the intra-patient comparison of the HAVEN 3 trial

Objectives: To compare the efficacy of emicizumab prophylaxis with that of factor VIII (FVIII) prophylaxis in patients with hemophilia A without inhibitors using two approaches: network meta-analyses (NMA) and additional sub-group analyses from the HAVEN 3 trial.Methods: The NMA used data from trials identified using a systematic literature review and compared bleed rates in patients receiving emicizumab prophylaxis and patients receiving FVIII prophylaxis using a Bayesian, random effects generalized linear model with log link Poisson likelihood. Additional sub-groups of the HAVEN 3 trial included here were defined as patients whose dose-taking behavior met either European label or World Federation of Hemophilia guidelines. A negative binomial regression model was used to conduct an intra-patient comparison of bleed rates within the sub-groups, during treatment with FVIII prophylaxis before entering HAVEN 3 and treatment with emicizumab prophylaxis during HAVEN 3.Results: Four studies were included in the base-case NMA. Evidence showed that the total treated bleed rate was lower with emicizumab prophylaxis compared with FVIII prophylaxis (rate ratio [RR] = 0.36 [95% credible interval (CrI) = 0.13-0.95]). Similar associations were observed in sensitivity analyses. The additional HAVEN 3 analyses also showed lower rates of treated bleeds with emicizumab prophylaxis than with FVIII prophylaxis (RRs [95% confidence interval (CI)] = 0.380 [0.186-0.790] and 0.472 [0.258-0.866] in two sub-groups). These results confirm the original HAVEN 3 intra-patient comparison findings.Conclusions: Combined findings from NMA and additional sub-group analyses of HAVEN 3 support the superiority of emicizumab prophylaxis over FVIII prophylaxis in patients with hemophilia A without inhibitors.

Antibody-Based Ticagrelor Reversal Agent in Healthy Volunteers

BACKGROUND

Ticagrelor is an oral P2Y₁₂ inhibitor that is used with aspirin to reduce the risk of ischemic events among patients with acute coronary syndromes or previous myocardial infarction. Spontaneous major bleeding and bleeding associated with urgent invasive procedures are concerns with ticagrelor, as with other antiplatelet drugs. The antiplatelet effects of ticagrelor cannot be reversed with platelet transfusion. A rapid-acting reversal agent would be useful.

METHODS

In this randomized, double-blind, placebo-controlled, phase 1 trial, we evaluated intravenous PB2452, a monoclonal antibody fragment that binds ticagrelor with high affinity, as a ticagrelor reversal agent. We assessed platelet function in healthy volunteers before and after 48 hours of ticagrelor pretreatment and again after the administration of PB2452 or placebo. Platelet function was assessed with the use of light transmission aggregometry, a point-of-care P2Y₁₂ platelet-reactivity test, and a vasodilator-stimulated phosphoprotein assay.

RESULTS

Of the 64 volunteers who underwent randomization, 48 were assigned to receive PB2452 and 16 to receive placebo. After 48 hours of ticagrelor pretreatment, platelet aggregation was suppressed by approximately 80%. PB2452 administered as an initial intravenous bolus followed by a prolonged infusion (8, 12, or 16 hours) was associated with a significantly greater increase in platelet function than placebo, as measured by multiple assays. Ticagrelor reversal occurred within 5 minutes after the initiation of PB2452 and was sustained for more than 20 hours (P<0.001 after Bonferroni adjustment across all time points for all assays). There was no evidence of a rebound in platelet activity after drug cessation. Adverse events related to the trial drug were limited mainly to issues involving the infusion site.

CONCLUSIONS

In healthy volunteers, the administration of PB2452, a specific reversal agent for ticagrelor, provided immediate and sustained reversal of the antiplatelet effects of ticagrelor, as measured by multiple assays. (Funded by PhaseBio Pharmaceuticals; ClinicalTrials.gov number, NCT03492385.).

Laboratory assay measurement of modified clotting factor concentrates: a review of the literature and recommendations for practice

Over the past several years, novel modified clotting factor concentrates (CFCs) have been introduced into practice and are now widely prescribed in the countries where they are licensed. These products allow for less frequent infusions of CFC, thereby providing improved convenience and/or higher trough levels. They have been extensively studied for prophylaxis, episodic treatment of bleeding and for surgical prophylaxis. One issue that has emerged regarding the clinical application of these products revolves around the measurement of infused CFC in the clinical coagulation laboratory. Recent studies have demonstrated significant problems with the measurement of correct FVIII/IX levels following infusion of novel CF VIII/IX concentrates. The source of this problem appears to be related to the tremendous variability of the APTT reagents that are used in the one-stage clotting assay, the most commonly used assay for determining factor levels. More specifically, the issue is related to the type of activator used in the reagents. Depending on the combination of the CFC and the APTT activator, the observed results may be either under- or overestimated to degrees that would be clinically relevant. Recommendations based on a review of published information regarding the potential for incorrect measurements of factor VIII/IX levels following infusion of recently developed, novel factor VIII/IX CFCs are presented for the clinician to use in clinical practice.

Phase 3 study of recombinant von Willebrand factor in patients with severe von Willebrand disease who are undergoing elective surgery

Essentials Recombinant von Willebrand factor (rVWF) is effective in von Willebrand disease (VWD). A phase 3 study of rVWF, with/without recombinant factor VIII (rFVIII) before surgery in VWD. Overall rVWF's efficacy was rated excellent/good; rVWF was administered alone in most patients. rVWF was well-tolerated and hemostasis was achieved in patients with severe VWD undergoing surgery. SUMMARY: Background Recombinant von Willebrand factor (rVWF) has demonstrated efficacy for on-demand treatment of bleeding in severe von Willebrand disease (VWD), warranting evaluation in the surgical setting. Objectives This study (NCT02283268) evaluated the hemostatic efficacy/safety profile of rVWF, with/without recombinant factor VIII (rFVIII), in patients with severe VWD undergoing surgery. Patients/Methods Patients received rVWF 40-60 IU kg-1 , VWF ristocetin cofactor activity was measured 12-24 h before surgery. If endogenous FVIII activity (FVIII:C) target levels were achieved 3 h before surgery, rVWF was administered alone 1 h before surgery; rVWF was co-administered with rFVIII if target endogenous FVIII levels were not achieved. rVWF was infused postoperatively to maintain target trough levels. Overall and intraoperative hemostatic efficacy, the pharmacodynamics of rVWF administration and the incidence of adverse events (AEs) were assessed. Results All patients treated with rVWF for major (n = 10), minor (n = 4) and oral (n = 1) surgery had overall and intraoperative hemostatic efficacy ratings of excellent (73.3% and 86.7%) or good (26.7% and 13.3%). Most rVWF infusions (89.4%) were administered alone, resulting in hemostatically effective levels of endogenous FVIII within 6 h, which were sustained for 72-96 h; 70% (n = 7/10) of major surgeries were performed without rFVIII co-administration. Six patients reported 12 treatment-emergent AEs. Two patients each had one serious AE: diverticulitis (not treatment related) and deep vein thrombosis (sponsor-assessed as possibly treatment related). No severe allergic reactions or inhibitory antibodies were reported. Conclusions These data support the efficacy and safety profile of rVWF in patients with severe VWD undergoing elective surgery.

The future of bypassing agents for hemophilia with inhibitors in the era of novel agents

Bypassing agents are presently the standard of care for the treatment of bleeding episodes in patients with hemophilia and high-titer inhibitors and are also used for bleed prevention. Only two bypassing agents are available to patients, and these products trace their lineage to the 1970s (activated prothrombin complex concentrates) and the 1980s (recombinant factor VIIa). Given the limited repertoire of available products, clinicians have relied on experience, empirical observation, registry data and individualized care to improve clinical outcomes on a case-by-case basis. Research over the past two decades has culminated in a greatly improved understanding of human coagulation; resulting from this, new products have been developed that offer treatment options and mechanisms of actions that differ from current bypassing agents. The most advanced in clinical development is emicizumab, a bispecific antibody that mimics the function of FVIIIa in the intrinsic Xase complex and is indicated for once-weekly or every-other-week prophylactic dosing in inhibitor patients. Other non-traditional products in clinical development include fitusiran and antibodies directed against tissue factor pathway inhibitor. As non-factor-based therapies become more widely utilized over time, the use of bypassing agents may be expected to decrease; however, bypassing agents will remain essential for the foreseeable future. As such, clinical development of bypassing agents continues, with some products (e.g. eptacog beta) under regulatory review. In this review we examine the optimal use of bypassing agents and their mechanism of action. We also discuss newer products and how these might theoretically be administered in conjunction with traditional bypassing agents.

Phase 1, single-dose escalating study of marzeptacog alfa (activated), a recombinant factor VIIa variant, in patients with severe hemophilia

Essentials Marzeptacog alfa (activated) [MarzAA] is a novel variant of activated human factor VII. A phase 1 dose escalation trial of MarzAA was conducted in subjects with severe hemophilia. MarzAA was safe and tolerated at intravenous doses up to 30 μg kg-1 Data observed support further trials for hemophilia patients with inhibitors to factors VIII/IX.

SUMMARY

Background Marzeptacog alfa (activated) (MarzAA), a new recombinant activated human factor VII (rFVIIa) variant with four amino acid substitutions, was developed to provide increased procoagulant activity and a longer duration of action in people with hemophilia. Objectives To investigate the safety, tolerability, immunogenicity, pharmacokinetics (PK) and pharmacodynamics (PD) of single ascending intravenous bolus doses of MarzAA in non-bleeding patients with congenital hemophilia A or B with or without inhibitors. Methods This international, phase 1, open-label study (NCT01439971) enrolled males aged 18-64 years with severe hemophilia A or B, with or without FVIII or FIX inhibitors. Subjects were assigned to single-dose MarzAA cohorts (0.5, 4.5, 9, 18 or 30 μg kg-1 ). Blood sampling was performed predose and postdose, and subjects were monitored for 60 days postdose. Safety endpoints included adverse events, vital sign changes, electrocardiograms, laboratory abnormalities, and immunogenicity; secondary endpoints included evaluation of PK and PD. Results Overall, in 25 patients, MarzAA was well tolerated at all dose levels tested, and was not associated with dose-limiting toxicity. No treatment-emergent severe or serious adverse events occurred. MarzAA showed linear dose-response PK across the 4.5-30 μg kg-1 dose range, with a terminal half-life of ⁓ 3.5 h. Dose-dependent shortening of the activated partial thromboplastin time and prothrombin time, and evidence of an increase in peak thrombin as determined with a thrombin generation assay, were observed at all doses. Conclusions MarzAA was tolerated at doses up to 30 μg kg-1 . The safety profile and pharmacological effects observed support further clinical trials for the treatment of hemophilic patients with inhibitors.

Factor VIII products and inhibitor development in previously treated patients with severe or moderately severe hemophilia A: a systematic review

Essentials Data on product-related immunogenicity in previously treated haemophilia A patients is scarce. A systematic review and meta-analysis of all currently available evidence was conducted. The overall incidence rate was 2.06 per 1000 person-years (95% confidence interval: 1.06-4.01). Some recombinant factor VIII products were associated with increased immunogenicity.

SUMMARY

Background Patients with severe hemophilia A who have been treated extensively with factor VIII products have a low but potentially serious risk of inhibitor development. It is unknown why these patients develop inhibitors, and data on product-related immunogenicity are scarce. Aims To summarize the currently available evidence on the relationship between inhibitor development and recombinant FVIII product type in previously treated patients (PTPs) with severe hemophilia A. Methods Longitudinal studies were included that reported on de novo inhibitor formation in patients with baseline FVIII activity levels of < 0.02 IU mL-1 who had been treated with FVIII for at least 50 days. Pooled incidence rates of inhibitor development according to product types were calculated with a random intercept Poisson regression model. Results Forty-one independent cohorts were included; 39 patients developed de novo inhibitors during 19 157 person-years of observation. The overall incidence rate was 2.06 per 1000 person-years, with a 95% confidence interval (CI) of 1.06-4.01. According to product type, the pooled incidence rates were 0.99 (95% CI 0.37-2.70) per 1000 person-years for patients treated with Advate, 5.86 (95% CI 0.25-134.92) per 1000 person-years for those treated with Kogenate/Helixate, 1.35 (95% CI 0.66-2.77) per 1000 person-years for those treated with Kogenate FS/Helixate NexGen, 12.05 (95% CI 1.53-94.78) per 1000 person-years for those treated with Refacto, and 4.64 (95% CI 0.82-26.43) per 1000 person-years for those treated with Refacto AF. Conclusion These results suggest that some products may be associated with increased immunogenicity. However, the low incidence of inhibitors in PTPs and the differences in study design may cause significant variation in estimates of risk.

Efficacy, safety and pharmacokinetics of a new high-purity factor X concentrate in women and girls with hereditary factor X deficiency

Essentials Plasma-derived factor X concentrate (pdFX) is used to treat hereditary factor X deficiency. pdFX pharmacokinetics, safety and efficacy were assessed in factor X-deficient women/girls. Treatment success rate was 98%; only 6 adverse events in 2 subjects were possibly pdFX related. On-demand pdFX 25 IU kg-1 was effective and safe in women/girls with factor X deficiency.

SUMMARY

Background A high-purity, plasma-derived factor X concentrate (pdFX) has been approved for the treatment of hereditary FX deficiency, an autosomal recessive disorder. Objective To perform post hoc assessments of pdFX pharmacokinetics, safety and efficacy in women and girls with hereditary FX deficiency. Patients/Methods Subjects aged ≥ 12 years with moderate/severe FX deficiency (plasma FX activity of < 5 IU dL-1 ) received on-demand or preventive pdFX (25 IU kg-1 ) for ≤ 2 years. Results Of 16 enrolled subjects, 10 women and girls (aged 14-58 years [median, 25.5 years]) received 267 pdFX infusions. Mean monthly infusions per subject were higher among women and girls (2.48) than among men and boys (1.62). In women and girls, 132 assessable bleeding episodes (61 heavy menstrual bleeds, 47 joint bleeds, 15 muscle bleeds, and nine other bleeds) were treated with pdFX, with a 98% treatment success rate versus 100% in men and boys. Mean pdFX incremental recovery was similar in the two groups (2.05 IU dL-1 versus 1.91 IU dL-1 per IU kg-1 ), as was the mean half-life (29.3 h versus 29.5 h). Of 142 adverse events in women and girls, headache was the most common (12 events in six subjects). Six events (two infusion-site erythema, two fatigue, one back pain, one infusion-site pain) in two subjects were considered to be possibly pdFX-related. Following the trial, pdFX was used to successfully maintain hemostasis in two subjects undergoing obstetric delivery. Conclusions pdFX was well tolerated and effective in women and girls with FX deficiency. Although women and girls had different bleeding symptoms and sites than men and boys, their pdFX pharmacokinetic profile was comparable.

Viral safety of coagulation factor concentrates: memoirs from an insider

The purpose of this essay is to recall the actions taken globally to improve the viral safety of coagulation factor concentrates, mainly in the years 1985-1990, at a time of confusing and often contradictory information on bloodborne viral infections in multitransfused patients with hemophilia (PWHs). I shall first recall the problem of the transmission and control of the hepatitis viruses, and then that of HIV: not only for temporal reasons, but also because understanding the progress of knowledge on hepatitis and the poor success of the early measures taken to tackle this problem in PWHs is essential to understand how the problem of HIV transmission was ultimately dealt with successfully.

Pharmacokinetics, clot strength and safety of a new fibrinogen concentrate: randomized comparison with active control in congenital fibrinogen deficiency

Essentials Congenital afibrinogenemia causes a potentially life-threatening bleeding and clotting tendency. Two human fibrinogen concentrates (HFCs) were compared in a randomized pharmacokinetic study. Bioequivalence was not shown for AUCnorm , which was significantly larger for the new HFC. Increases in clot strength were comparable, and no thromboses or deaths occurred in the study.

SUMMARY

Background Human fibrinogen concentrate (HFC) corrects fibrinogen deficiency in congenital a-/hypofibrinogenemia. 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 afibrinogenemia patients aged ≥ 12 years, 70 mg kg-1 of new HFC (FIBRYGA, Octapharma AG) or control (Haemocomplettan® 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% confidence interval [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.

Factor XIII cotreatment with hemostatic agents in hemophilia A increases fibrin α-chain crosslinking

Essentials Factor XIII (FXIII)-mediated fibrin crosslinking is delayed in hemophilia. We determined effects of FXIII cotreatment with hemostatic agents on clot parameters. FXIII cotreatment accelerated FXIII activation and crosslinking of fibrin and α2 -antiplasmin. These data provide biochemical rationale for FXIII cotreatment in hemophilia.

SUMMARY

Background Hemophilia A results from the absence, deficiency or inhibition of factor VIII. Bleeding is treated with hemostatic agents (FVIII, recombinant activated FVII [rFVIIa], anti-inhibitor coagulation complex [FEIBA], or recombinant porcine FVIII [rpFVIII]). Despite treatment, some patients have prolonged bleeding. FXIII-A2 B2 (FXIII) is a protransglutaminase. During clot contraction, thrombin-activated FXIII (FXIIIa) crosslinks fibrin and α2 -antiplasmin, which promotes red blood cell retention and increases clot stability and weight. We hypothesized that FXIII cotreatment in hemophilia would accelerate FXIII activation, leading to increased fibrin crosslinking. Methods FVIII-deficient plasma and whole blood were clotted with or without hemostatic agents (FVIII, rFVIIa, FEIBA, or recombinant B-domain-deleted porcine FVIII [rpFVIII]) and/or FXIII. The effects on FXIII activation, thrombin generation, fibrin and α2 -antiplasmin crosslinking, clot formation and clot weight were measured by western blotting, calibrated automated thrombography, thromboelastography, and clot contraction assays. Results As compared with FVIII-treated hemophilic plasma, FVIII + FXIII cotreatment accelerated FXIIIa formation without increasing thrombin generation. As compared with buffer-treated or FXIII-treated hemophilic plasma, FVIII treatment and FVIII + FXIII cotreatment increased the generation and amount of crosslinked fibrin, including α-chain-rich high molecular weight species and crosslinked α2 -antiplasmin. In the presence of FVIII inhibitors, as compared with hemostatic treatments (rFVIIa, FEIBA, or rpFVIII) alone, FXIII cotreatment increased whole blood clot weight. Conclusion In hemophilia A plasma and whole blood, FXIII cotreatment with hemostatic agents accelerated FXIIIa formation, increased the generation and amount of fibrin α-chain crosslinked species, accelerated α2 -antiplasmin crosslinking, and increased clot weight. FXIII cotreatment with hemostatic therapy may augment hemostasis through increased crosslinking of fibrin and α2 -antiplasmin.

Timing and severity of inhibitor development in recombinant versus plasma-derived factor VIII concentrates: a SIPPET analysis

Essentials Recombinant factor VIII (rFVIII) was contrasted with plasma-derived FVIII (pdFVIII). In previously untreated patients with hemophilia A, rFVIII led to more inhibitors than pdFVIII. Inhibitors with rFVIII developed earlier, and the peak rate was higher than with pdFVIII. Inhibitors with rFVIII were more severe (higher titre) than with pdFVIII.

SUMMARY

Background The development of neutralizing antibodies (inhibitors) against factor VIII (FVIII) is the most severe complication in the early phases of treatment of severe hemophilia A. Recently, a randomized trial, the Survey of Inhibitors in Plasma-Product Exposed Toddlers (SIPPET) demonstrated a 2-fold higher risk of inhibitor development in children treated with recombinant FVIII (rFVIII) products than with plasma-derived FVIII (pdFVIII) during the first 50 exposure days (EDs). Objective/Methods In this post-hoc SIPPET analysis we evaluated the rate of inhibitor incidence over time by every 5 EDs (from 0 to 50 EDs) in patients treated with different classes of FVIII product, made possible by a frequent testing regime. Results The highest rate of inhibitor development occurred in the first 10 EDs, with a large contrast between rFVIII and pdFVIII during the first 5 EDs: hazard ratio 3.14 (95% confidence interval [CI], 1.01-9.74) for all inhibitors and 4.19 (95% CI, 1.18-14.8) for high-titer inhibitors. For patients treated with pdFVIII, the peak of inhibitor development occurred later (6-10 EDs) and lasted for a shorter time. Conclusion These results emphasize the high immunologic vulnerability of patients during the earliest exposure to FVIII concentrates, with the strongest response to recombinant FVIII products.

Reversal of apixaban anticoagulation by four-factor prothrombin complex concentrates in healthy subjects: a randomized three-period crossover study

Essentials Prothrombin complex concentrates (PCCs) may reverse the effect of factor Xa (FXa) inhibitors. We conducted an open-label, randomized, placebo-controlled, three-period crossover study in 15 subjects. Both PCCs rapidly reversed apixaban-mediated decreases in mean endogenous thrombin potential. Four-factor PCC administration had no effect on apixaban pharmacokinetics or anti-FXa activity.

SUMMARY

Background Currently, there is no approved reversal agent for direct activated factor Xa (FXa) inhibitors; however, several agents are under investigation, including prothrombin complex concentrates (PCCs). Objective This open-label, randomized, placebo-controlled, three-period crossover study assessed the effect of two four-factor PCCs on apixaban pharmacodynamics and pharmacokinetics in 15 healthy subjects. Methods Subjects received apixaban 10 mg twice daily for 3 days. On day 4, 3 h after apixaban, subjects received a 30-min infusion of 50 IU kg-1 Cofact, Beriplex P/N (Beriplex), or saline. Change in endogenous thrombin potential (ETP), measured with a thrombin generation assay (TGA), was the primary endpoint. Secondary endpoints included changes in other TGA parameters, prothrombin time (PT), International Normalized Ratio (INR), activated partial thromboplastin time, anti-FXa activity, apixaban pharmacokinetics, and safety. Results Apixaban-related changes in ETP and several other pharmacodynamic measures occurred following apixaban administration. Both PCCs reversed apixaban's effect on ETP; the differences in adjusted mean change from pre-PCC baseline to end of infusion were 425 nm min (95% confidence interval [CI] 219.8-630.7 nm min; P < 0.001) for Cofact, and 91 nm min (95% CI - 31.3 to 212.4 nm min; P > 0.05) for Beriplex. Both PCCs returned ETP to pre-apixaban baseline levels 4 h after PCC infusion, versus 45 h for placebo. For both PCCs, mean ETP peaked 21 h after PCC initiation, and then slowly decreased over the following 48 h. Both PCCs reversed apixaban's effect on TGA peak height, PT, and INR. Apixaban pharmacokinetic and anti-FXa profiles were consistent across treatments. Conclusions Cofact and Beriplex reversed apixaban's steady-state effects on several coagulation assessments.

Recombinant factor XIII prophylaxis is safe and effective in young children with congenital factor XIII-A deficiency: international phase 3b trial results

Essentials Prophylaxis is the standard of care for congenital factor XIII-A (FXIII-A) deficiency. Six children with FXIII-A deficiency received once-monthly prophylaxis with recombinant FXIII-A. Prophylaxis was well tolerated and no anti-FXIII antibodies were detected. Prophylaxis was effective with an annualized bleeding rate of zero.

SUMMARY

Background Factor XIII deficiency is a rare, severe congenital bleeding disorder. Monthly prophylaxis with recombinant FXIII A-Subunit (rFXIII) has demonstrated favorable safety and efficacy in patients aged ≥ 6 years, and may similarly benefit younger children. Objective To evaluate the long-term safety and efficacy of rFXIII in children aged < 6 years with congenital FXIII A-subunit deficiency. Patients/methods Six children, who had previously completed a single-dose pharmacokinetic trial of rFXIII, received 35 IU kg-1 rFXIII every 28 days (± 2 days) for a minimum of 52 weeks, and were evaluated for bleeding and adverse events. The Berichrom FXIII activity assay was used to monitor FXIII activity. Results The children, three girls and three boys, had an average age of 3.0 years (range: 1-4 years) at enrollment. The total treatment duration was 1.8-3.5 years, giving a total of 16.6 patient-years. No antibody development, thromboembolic events or allergic reactions occurred. There were 93 mild and seven moderate adverse events. Two adverse events (lymphopenia and gastroenteritis) were reported as probably or possibly related to rFXIII in two children. Two serious adverse events, unrelated to rFXIII, were reported in a single child, each related to head injury, and neither resulting in intracranial hemorrhage. The geometric mean FXIII activity trough was 0.19 IU mL-1 . No bleeding episodes requiring treatment with an FXIII-containing hemostatic agent occurred during the trial; thus, the annualized bleeding rate was 0. Conclusions Consistent with data from older age groups, prophylaxis with rFXIII appears to be safe and effective in young children with congenital FXIII A-subunit deficiency.

Phase 1 dose-escalating study to evaluate the safety, pharmacokinetics, and pharmacodynamics of a recombinant factor Xa variant (FXaI16L )

Essentials FXaI16L is a recombinant zymogen-like variant of activated coagulation factor X (FXa). A phase 1 dose escalation clinical trial of FXaI16L was conducted in healthy adults. FXaI16L was safe and tolerated at doses up to 5 μg/kg; no dose-limiting toxicity was observed. Data support further development of FXaI16L for patients with acute hemorrhagic conditions.

SUMMARY

Background FXaI16L (PF-05230907) is a zymogen-like variant of activated factor X (FXa). It shows enhanced resistance to inactivation by endogenous inhibitors as compared with wild-type FXa, and restores hemostatic activity in non-clinical models of various bleeding conditions. Objectives To evaluate the safety, pharmacokinetics and pharmacodynamics of FXaI16L by performing a phase 1, first-in-human, dose-escalation clinical trial in healthy adult volunteers. Methods Participants were assigned to one of six ascending single-dose cohorts (0.1, 0.3, 1, 2, 3 or 5 μg kg-1 ), each planned to comprise six volunteers treated with FXaI16L and two treated with placebo. Assessments included safety monitoring, pharmacokinetic and pharmacodynamic (PD) analyses, and immunogenicity testing. Results The trial enrolled 49 male volunteers. Administration of a single intravenous bolus dose of FXaI16L was safe and tolerated at all dose levels tested, with no dose-limiting toxicity or serious adverse events. FXaI16L plasma levels appeared to increase dose-proportionally, with a half-life of ~ 4 min. Treatment-related PD changes were observed for activated partial thromboplastin time, thrombin generation assay, thrombin-antithrombin complexes, prothrombin fragment 1 + 2, and D-dimer. One volunteer had a weak and transient non-neutralizing antidrug antibody response, which did not cross-react with native FX or native FXa. Conclusions FXaI16L was safe and tolerated, and showed a pharmacologic effect in healthy adults when administered at doses up to 5 μg kg-1 . The safety profile, pharmacokinetics and pharmacodynamics observed in this clinical trial support the further development of FXaI16L for hemostatic treatment in individuals with acute hemorrhagic conditions.

Medical Treatment for Spontaneous Anticoagulation-Related Intracerebral Hemorrhage in the Netherlands

BACKGROUND

Spontaneous anticoagulation-related intracerebral hemorrhage accounts for up to a quarter of spontaneous intracerebral hemorrhage cases and is associated with higher hematoma volume and a worse outcome. Guidelines recommend rapid anticoagulant reversal but mode and timing are not specified and optimal strategy is uncertain. Variability in everyday practice is unknown.

METHODS

An invitation to a web-based survey was sent to 85 Dutch stroke neurologists in different hospitals, with questions about importance, timing, and medical management of spontaneous anticoagulation-related intracerebral hemorrhage.

RESULTS

In total, 61 (72%) neurologists completed the survey. Nearly all (97%) deemed rapid anticoagulant reversal important. A local guideline for management of anticoagulant reversal was used in 80% of the hospitals. Most neurologists (56%) estimated anticoagulant reversal in anticoagulation-related intracerebral hemorrhage to start later than intravenous thrombolysis in ischemic stroke. Few (5%) thought it was quicker. A minority (28%) of the hospitals started anticoagulation reversal without waiting for laboratory test results or consulting a specialist in hemostasis. Prothrombin complex concentrate was used by all neurologists for vitamin K antagonist reversal and by most (74%) for reversal of thrombin inhibitors and factor Xa inhibitors (72%). Anticoagulation reversal was initiated at the emergency department according to 89% of the respondents.

CONCLUSION

Variability in logistics in acute management of spontaneous anticoagulation-related intracerebral hemorrhage was demonstrated. Anticoagulant reversal is deemed important, but is estimated to have a longer door-to-needle time than alteplase in thrombolysis for ischemic stroke by most neurologists. Several delaying factors were found. These factors might have an impact on outcome.

Perioperative treatment of hemophilia A patients: blood group O patients are at risk of bleeding complications

ESSENTIALS: Targeting of factor VIII values is a challenge during perioperative replacement therapy in hemophilia. This study aims to identify the extent and predictors of factor VIII underdosing and overdosing. Blood group O predicts underdosing and is associated with perioperative bleeding. To increase quality of care and cost-effectiveness of treatment, refining of dosing is obligatory.

SUMMARY

BACKGROUND

Perioperative administration of factor VIII (FVIII) concentrate in hemophilia A may result in both underdosing and overdosing, leading to respectively a risk of bleeding complications and unnecessary costs.

OBJECTIVES

This retrospective observational study aims to identify the extent and predictors of underdosing and overdosing in perioperative hemophilia A patients (FVIII levels < 0.05 IU mL(-1)).

PATIENTS AND METHODS

One hundred nineteen patients undergoing 198 elective, minor, or major surgical procedures were included (median age 40 years, median body weight 75 kg). Perioperative management was evaluated by quantification of perioperative infusion of FVIII concentrate and achieved FVIII levels. Predictors of underdosing and (excessive) overdosing were analyzed by logistic regression analysis. Excessive overdosing was defined as upper target level plus ≥ 0.20 IU mL(-1).

RESULTS

Depending on postoperative day, 7-45% of achieved FVIII levels were under and 33-75% were above predefined target ranges as stated by national guidelines. A potential reduction of FVIII consumption of 44% would have been attained if FVIII levels had been maintained within target ranges. Blood group O and major surgery were predictive of underdosing (odds ratio [OR] 6.3, 95% confidence interval [CI] 2.7-14.9; OR 3.3, 95% CI 1.4-7.9). Blood group O patients had more bleeding complications in comparison to patients with blood group non-O (OR 2.02, 95% CI 1.00-4.09). Patients with blood group non-O were at higher risk of overdosing (OR 1.5, 95% CI 1.1-1.9). Additionally, patients treated with bolus infusions were at higher risk of excessive overdosing (OR 1.8, 95% CI 1.3-2.4).

CONCLUSION

Quality of care and cost-effectiveness can be improved by refining of dosing strategies based on individual patient characteristics such as blood group and mode of infusion.

Clotting factor product administration and same-day occurrence of thrombotic events, as recorded in a large healthcare database during 2008-2013

BACKGROUND

Thrombotic events (TEs) are serious adverse events that can occur following administration of clotting factors (CFs).

OBJECTIVES

To evaluate occurrence of same-day TEs for different CF products and potential risk factors.

METHODS

A retrospective cohort study of individuals exposed to CF products during 2008-2013 was conducted using a large commercial insurance database. CF products were identified by procedure codes, and TEs were ascertained via diagnosis codes. Crude same-day TE rates (per 1000 persons exposed) were estimated overall and by congenital factor deficiency (CFD) status, CF products, age and gender. Multivariable logistic regression analyses were used to control for confounding. Laboratory analysis was used to compare the procoagulant activities of FIX products.

RESULTS

Of 3801 individuals exposed to CFs, 117 (30.8 per 1000) had same-day TEs recorded. The crude same-day TE rate was higher for CF users without CFD, 70.2 (102 of 1452), as compared with those with CFD, 6.4 (15 of 2349) (RR, 11.0; 95% CI, 6.4-18.9). For individuals without CFD, a significantly increased same-day TE risk was identified for factor IX complex (OR, 6.92; 95% CI, 3.11-15.40), factor VIIa (OR, 9.42; 95% CI, 4.99-17.78) and other products when compared with fibrin sealant. An increased risk of a TE was found with older age (≥ 45 years), history of TEs and underlying health conditions. The laboratory identified elevated procoagulant activity in Profilnine(®) and Benefix(®) .

CONCLUSIONS

The study shows an increased same-day TE risk for CF users without CFD and suggests substantial off-label CF use. The study findings also show elevated same-day TE rates for different CF products and suggest the importance of product properties and patient factors.

Pediatric transplantation: managing bleeding

There has been extraordinary progress over the last half-century in the field of medical transplantation in which tissue, organs, or body parts from one human are placed into another. Solid organ transplants have allowed thousands of children with otherwise devastating inherited or acquired disorders to survive. Depending upon the clinical situation, there are many specific peri-transplant issues that must be carefully addressed to optimize outcomes. Although surgical, immunologic, and infectious concerns are usually in the forefront, important aspects regarding hemostasis frequently arise. The number of solid organs that can be successfully transplanted in children has expanded over the last decades and includes kidney, liver, heart, lung, intestine, pancreas, and thymus. Bleeding complications may occur in the setting of organ failure prior to transplantation, during the surgical procedure, or in the post-transplant setting, and can results in significant morbidity. This report will focus on preventing and managing non-surgical-related bleeding complications in children undergoing liver, heart, kidney transplantation, in whom there are often unique aspects of coagulation to be considered.

Recombinant factor VIII Fc fusion protein for the prevention and treatment of bleeding in children with severe hemophilia A

BACKGROUND

Prophylactic factor replacement, which prevents hemarthroses and thereby reduces the musculoskeletal disease burden in children with hemophilia A, requires frequent intravenous infusions (three to four times weekly).

OBJECTIVE

Kids A-LONG was a phase 3 open-label study evaluating the safety, efficacy and pharmacokinetics of a longer-acting factor, recombinant factor VIII Fc fusion protein (rFVIIIFc), in previously treated children with severe hemophilia A (endogenous FVIII level of < 1 IU dL(-1) [< 1%]).

METHODS

The study enrolled 71 subjects. The starting rFVIIIFc regimen was twice-weekly prophylaxis (Day 1, 25 IU kg(-1) ; Day 4, 50 IU kg(-1) ); dose (≤ 80 IU kg(-1) ) and dosing interval (≥ 2 days) were adjusted as needed. A subset of subjects had sequential pharmacokinetic evaluations of FVIII and rFVIIIFc. The primary endpoint was development of inhibitors (neutralizing antibodies). Secondary endpoints included pharmacokinetics, annualized bleeding rate (ABR), and number of infusions required to control a bleed.

RESULTS

No subject developed an inhibitor to rFVIIIFc. Adverse events were typical of a pediatric hemophilic population. The rFVIIIFc half-life was prolonged relative to that of FVIII, consistent with observations in adults and adolescents. The median ABR was 1.96 overall, and 0.00 for spontaneous bleeds; 46.4% of subjects reported no bleeding episodes on study. Ninety-three per cent of bleeding episodes were controlled with one to two infusions. The median average weekly rFVIIIFc prophylactic dose was 88.11 IU kg(-1) . At study end, 62 of 69 subjects (90%) were infusing twice weekly. Among subjects who had been previously receiving FVIII prophylaxis, 74% reduced their dosing frequency with rFVIIIFc.

CONCLUSION

Twice-weekly infusions with rFVIIIFc were well tolerated and yielded low bleeding rates in children with severe hemophilia A.

Anti-A2 and anti-A1 domain antibodies are potential predictors of immune tolerance induction outcome in children with hemophilia A

BACKGROUND

Hemophilia A (HA) is a congenital bleeding disorder resulting from factor VIII deficiency. The most serious complication of HA management is the appearance of inhibitory antibodies (Abs) against injected FVIII concentrates. To eradicate inhibitors, immune tolerance induction (ITI) is usually attempted, but it fails in up to 30% of cases. Currently, no undisputed predictive marker of ITI outcome is available to facilitate the clinical decision.

OBJECTIVES

To identify predictive markers of ITI efficacy.

METHODS

The isotypic and epitopic repertoires of inhibitory Abs were analyzed in plasma samples collected before ITI initiation from 15 children with severe HA and high-titer inhibitors, and their levels were compared in the two outcome groups (ITI success [n = 7] and ITI failure [n = 8]). The predictive value of these candidate biomarkers and of the currently used indicators (inhibitor titer and age at ITI initiation, highest inhibitor titer before ITI, and interval between inhibitor diagnosis and ITI initiation) was then compared by statistical analysis (Wilcoxon test and receiver receiver operating characteristic [ROC] curve analysis).

RESULTS

Whereas current indicators seemed to fail in discriminating patients in the two outcome groups (ITI success or failure), anti-A1 and anti-A2 Ab levels before ITI initiation appeared to be good potential predictive markers of ITI outcome (P < 0.018). ROC analysis showed that anti-A1 and anti-A2 Abs were the best at discriminating between outcome groups (area under the ROC curve of > 0.875).

CONCLUSION

Anti-A1 and anti-A2 Abs could represent new promising tools for the development of ITI outcome prediction tests for children with severe HA.

Recombinant human FVIIa for reducing the need for invasive second-line therapies in severe refractory postpartum hemorrhage: a multicenter, randomized, open controlled trial

BACKGROUND

Case reports on recombinant human factor VIIa (rhuFVIIa) use in women with severe postpartum hemorrhage (PPH) showed encouraging results, but no randomized controlled trial (RCT) is available.

PATIENTS AND METHODS

Eighty-four women with severe PPH unresponsive to uterotonics were randomized to receive one early single rhuFVIIa infusion (n = 42) or standard care (no rhuFVIIa; n = 42). The primary efficacy outcome measure was the reduction of the need for specific second-line therapies, such as interventional hemostatic procedures, for blood loss and transfusions. The primary safety outcome measure was the number of deaths and thrombotic events during the 5 days following rhuFVIIa infusion.

RESULTS

rhuFVIIa was associated with a reduction in the number of patients who needed second-line therapies compared with controls (standard care). Specifically, 39/42 (93%) patients in the standard care arm received second-line therapies and 22/42 (52%) patients in the rhuFVIIa arm (absolute difference, 41%; range, 18-63%; relative risk RR, 0.56 [0.42-0.76]). The delivery mode (vaginal or Cesarean section) did not affect the primary outcome. No death occurred. Two venous thrombotic events were recorded in the rhuFVIIa arm: one ovarian vein thrombosis and one deep vein thrombosis with a non-severe pulmonary embolism.

CONCLUSION

This open RCT in women with severe PPH refractory to uterotonics shows that rhuFVIIa reduces the need for specific second-line therapies in about one in three patients, with the occurrence of non-fatal venous thrombotic events in one in 20 patients.

The pharmacokinetics of a B-domain truncated recombinant factor VIII, turoctocog alfa (NovoEight®), in patients with hemophilia A

BACKGROUND

Turoctocog alfa (NovoEight(®)) is a human recombinant coagulation factor VIII (rFVIII) for the treatment of patients with hemophilia A.

OBJECTIVES

To evaluate the pharmacokinetics of turoctocog alfa in all age groups across clinical trials.

PATIENTS/METHODS

Data from previously treated patients with severe hemophilia A (FVIII activity level of ≤ 1%) with no history of FVIII inhibitors, in a non-bleeding state, were included. The pharmacokinetics were assessed following a wash-out period and a subsequent single intravenous 50 IU kg(-1) dose of turoctocog alfa. Blood was sampled during a 48-h period postdose. Standard pharmacokinetic (PK) parameters were estimated on the basis of plasma FVIII activity vs. time (PK profiles) with non-compartmental methods. Furthermore, a population PK analysis was conducted.

RESULTS

Data from 76 patients (aged 1-60 years) enrolled globally across six clinical trials were included, totaling 105 turoctocog alfa PK profiles. Single-dose PK results 3-6 months after the first dose of turoctocog alfa were comparable with the results obtained after the first dose. Similar PK characteristics were shown for different lots and strengths of the drug product. Overall, area under the plasma concentration (activity) curve from administration to infinity (AUC) and t1(/2) tended to increase with increasing age, with lower AUC and shorter t(1/2) being seen in children than in adolescents and adults. The PK profiles of turoctocog alfa and other commercially available plasma-derived FVIII and rFVIII products were similar in all age groups.

CONCLUSIONS

The PK characteristics of turoctocog alfa have been thoroughly studied, and shown to be consistent over time, reproducible between different lots and strengths of drug product, and similar to those observed for other FVIII products.

Prophylaxis vs. on-demand treatment with BAY 81-8973, a full-length plasma protein-free recombinant factor VIII product: results from a randomized trial (LEOPOLD II)

BACKGROUND

BAY 81-8973 is a new full-length human recombinant factor VIII product manufactured with technologies to improve consistency in glycosylation and expression to optimize clinical performance.

OBJECTIVES

To demonstrate superiority of prophylaxis vs. on demand therapy with BAY 81-8973 in patients with severe hemophilia A.

PATIENTS/METHODS

In this multinational,randomized, open-label crossover study (LEOPOLD II;ClinicalTrials.gov identifier: NCT01233258), males aged 12–65 years with severe hemophilia A were randomized to twice-weekly prophylaxis (20-30 IU kg(-1)), 3-times-weekly prophylaxis (30-40 IU kg(-1)), or on-demand treatment with BAY 81-8973. Potency labeling for BAY 81-8973 was based on the chromogenic substrate assay or adjusted to the one-stage assay. Primary efficacy endpoint was annualized number of all bleeds (ABR). Adverse events (AEs)and immunogenicity were also assessed.

RESULTS

Eighty patients (on demand, n = 21; twice-weekly prophylaxis, n = 28; 3-times-weekly prophylaxis, n = 31) were treated and analyzed. Mean ± SD ABR was significantly lower with prophylaxis (twice-weekly, 5.7 ± 7.2; 3-times-weekly, 4.3 ± 6.5; combined, 4.9 ± 6.8) vs. on-demand treatment (57.7 ± 24.6; P < 0.0001, ANOVA). Median ABR was reduced by 97% with prophylaxis (twice-weekly, 4.0;3-times-weekly, 2.0; combined, 2.0) vs. on-demand treatment (60.0). Median ABR was higher with twice-weekly vs. 3-times-weekly prophylaxis during the first 6-month treatment period (4.1 vs. 2.0) but was comparable in the second 6-month period (1.1 vs. 2.0). Few patients reported treatment-related AEs (4%); no treatment-related serious AEs or inhibitors were reported.

CONCLUSIONS

Twice weekly or 3-times-weekly prophylaxis with BAY 81-8973 reduced median ABR by 97% compared with on-demand therapy, confirming the superiority of prophylaxis. Treatment with BAY 81-8973 was well tolerated.

Cryoprecipitate therapy

Cryoprecipitate, originally developed as a therapy for patients with antihaemophilic factor deficiency, or haemophilia A, has been in use for almost 50 yr. However, cryoprecipitate is no longer administered according to its original purpose, and is now most commonly used to replenish fibrinogen levels in patients with acquired coagulopathy, such as in clinical settings with haemorrhage including cardiac surgery, trauma, liver transplantation (LT), or obstetric haemorrhage. Cryoprecipitate is a pooled product that does not undergo pathogen inactivation, and its administration has been associated with a number of adverse events, particularly transmission of blood-borne pathogens and transfusion-related acute lung injury. As a result of these safety concerns, along with emerging availability of alternative fibrinogen preparations, cryoprecipitate has been withdrawn from use in a number of European countries. Compared with the plasma from which it is prepared, cryoprecipitate contains a high concentration of coagulation factor VIII, coagulation factor XIII, and fibrinogen. Cryoprecipitate is usually licensed by regulatory authorities for the treatment of hypofibrinogenaemia, and recommended for supplementation when plasma fibrinogen levels decrease below 1 g litre(-1); however, this threshold is empiric and is not based on solid clinical evidence. Consequently, there is uncertainty over the appropriate dosing and optimal administration of cryoprecipitate, with some guidelines from professional societies to guide clinical practice. Randomized, controlled trials are needed to determine the clinical efficacy of cryoprecipitate, compared with the efficacy of alternative preparations. These trials will allow the development of evidence-based guidelines in order to inform physicians and guide clinical practice.

Recombinant factor VIII Fc fusion protein: extended-interval dosing maintains low bleeding rates and correlates with von Willebrand factor levels

BACKGROUND

Routine prophylaxis with replacement factor VIII (FVIII) - the standard of care for severe hemophilia A - often requires frequent intravenous infusions (three or four times weekly). An FVIII molecule with an extended half-life could reduce infusion frequency. The A-LONG study established the safety, efficacy and prolonged pharmacokinetics of recombinant FVIII Fc fusion protein (rFVIIIFc) in previously treated adolescents and adults with severe hemophilia A.

OBJECTIVE

In this post hoc analysis, we investigated the relationship between subjects' prestudy (FVIII) and on-study (rFVIIIFc) regimens.

METHODS

We analyzed two subgroups of subjects: prior prophylaxis and on-study individualized prophylaxis (n = 80), and prior episodic treatment and on-study weekly prophylaxis (n = 16). Subjects' prestudy dosing regimens and bleeding rates were compared with their final rFVIIIFc regimens and annualized bleeding rates (ABRs) in the last 3 months on-study. Dosing regimen simulations based on population pharmacokinetics models for rFVIII and rFVIIIFc were performed.

RESULTS

As compared with their prestudy regimen, 79 of 80 (98.8%) subjects on individualized rFVIIIFc prophylaxis decreased their infusion frequency. Overall ABRs were low, with comparable factor consumption. Longer dosing intervals, including 5-day dosing, were associated with higher baseline von Willebrand factor antigen levels. Simulated dosing regimens predicted a greater proportion of subjects with steady-state FVIII activity trough levels of ≥ 1 IU dL(-1) (1%) with rFVIIIFc than with equivalent rFVIII regimens.

CONCLUSION

These results suggest that patients on rFVIIIFc prophylaxis can reduce their infusion frequency as compared with their prior FVIII regimen while maintaining low bleeding rates, affording more patients trough levels of ≥ 1 IU dL(-1) than with rFVIII products requiring more frequent dosing regimens.

40K glycoPEGylated, recombinant FVIIa: 3-month, double-blind, randomized trial of safety, pharmacokinetics and preliminary efficacy in hemophilia patients with inhibitors

BACKGROUND

A 40K glycoPEGylated, recombinant activated factor VII (rFVIIa) bypassing agent (N7-GP) with a prolonged half-life (15 h) compared with rFVIIa was developed as a potential candidate for bleed-preventive regimens in patients with hemophilia and inhibitors.

OBJECTIVES

To evaluate the safety, pharmacokinetics and preliminary efficacy of multiple doses of N7-GP in congenital hemophilia A and B patients with high-titer inhibitors.

PATIENTS/METHODS

In this global, prospective, randomized, double-blinded, phase 2 trial, 25, 100 or 200 μg kg(-1)  N7-GP was administered intravenously once every second day during a 3-month, bleed-preventive regimen and compared with a preceding 3-month observation period with on-demand treatment of bleeds with rFVIIa. The primary endpoint was adverse events; secondary endpoints were evaluation of immunogenicity, pharmacokinetics and efficacy.

RESULTS AND CONCLUSIONS

Overall, 23 patients were randomized and dosed (n = 8/7/8 for 25/100/200 μg kg(-1) ). N7-GP was well tolerated, with a low frequency of adverse events. No serious adverse events, immunogenic or thromboembolic events related to N7-GP were reported. The pharmacokinetic properties of N7-GP were similar to those reported in phase 1. The annualized bleeding rate (ABR) decreased in the treatment period vs. the observation period at all N7-GP dose levels. However, a dose-response relationship in the reduction could not be established in the N7-GP dose range evaluated. The ABR was also reduced at two dose levels during the last part of the observation period, and increased notably in the follow-up period irrespective of previous N7-GP dose. The trial was registered at ClinicalTrials.gov (

REGISTRATION NUMBER

NCT00951405).

Musculoskeletal health of subjects with hemophilia A treated with tailored prophylaxis: Canadian Hemophilia Primary Prophylaxis (CHPS) Study

BACKGROUND

Full-dose prophylaxis is very effective at minimizing joint damage but is costly. Tailored prophylaxis has been proposed as a way of reducing costs while still protecting joints.

OBJECTIVE

To report detailed findings in index joints of 56 subjects with severe hemophilia A entered into the Canadian Hemophilia Prophylaxis Study, and treated with tailored prophylaxis, after 13 years.

METHODS

Boys with severe hemophilia A (< 2% factor) and normal joints were enrolled between the ages of 1 and 2.5 years. Initial treatment consisted of once-weekly factor infusions, with the frequency escalating in a stepwise fashion when breakthrough bleeding occurred. During the first 5 years, subjects were examined every 3 months using the modified Colorado Physical Evaluation (PE) scale; subsequently, every 6 months. The Childhood Health Assessment Questionnaire (CHAQ) was administered at each visit.

RESULTS

Median age at study entry was 19 months (range 12-30 months); median follow-up was 92 months (range 2-156). The median PE score was 2, 3 and 3 at ages 3, 6 and 10 years. Persistent findings were related to swelling, muscle atrophy and loss of range of motion. The median score for each of these items (for the six index joints) was 0 at ages 3, 6 and 10 years. The median overall CHAQ score was 0 at ages 3, 6 and 10 years, indicating excellent function.

CONCLUSIONS

Canadian boys treated with tailored primary prophylaxis exhibit minimal joint change on physical examination and minimal functional disability.

Phase I, randomized, double-blind, placebo-controlled, single-dose escalation study of the recombinant factor VIIa variant BAY 86-6150 in hemophilia

BACKGROUND

BAY 86-6150 is a new human recombinant factor VIIa variant developed for high procoagulant activity and longer action in people with hemophilia with inhibitors.

OBJECTIVES

To investigate the safety, tolerability, pharmacodynamics, pharmacokinetics and immunogenicity of BAY 86-6150 in non-bleeding hemophilia subjects.

METHODS

The study included non-bleeding men (18-65 years of age) with moderate or severe hemophilia A or B with or without inhibitors. Sixteen subjects were randomized 3 : 1 to four cohorts of escalating doses of BAY 86-6150 (6.5, 20, 50 or 90 μg kg(-1) [n = 3 per cohort]) or placebo (n = 1 per cohort); an independent data-monitoring committee reviewed previous cohort data before the next dose escalation. Blood sampling was performed predose and postdose; subjects were monitored for 50 days postdose.

RESULTS

At the tested doses, BAY 86-6150 was not associated with clinically significant adverse events or dose-limiting toxicities. BAY 86-6150 pharmacokinetics exhibited a linear dose response, with a half-life of 5-7 h. Subjects demonstrated consistent, dose-dependent thrombin generation ex vivo in platelet-poor plasma (PPP) (mean peak effect, 26-237 nm thrombin from 6.5 to 90 μg kg(-1)). Peak thrombin levels over time paralleled BAY 86-6150, with thrombin kinetics appearing to be slightly shorter; thus, circulating BAY 86-6150 retained activity. There were corresponding decreases in activated partial thromboplastin and prothrombin times. No subject developed de novo anti-BAY 86-6150 neutralizing antibodies during the 50-day follow-up.

CONCLUSIONS

In this first-in-human, multicenter, randomized, double-blind, placebo-controlled, single-dose escalation study, BAY 86-6150 was tolerated at the highest dose (90 μg kg(-1)), with no safety concerns. Safety and efficacy will be further evaluated in phase II/III studies.

Source and purity of factor VIII products as risk factors for inhibitor development in patients with hemophilia A

BACKGROUND

Inhibitor development is influenced by several factors and the type of factor VIII (FVIII) products may play a role.

OBJECTIVES

In order to explore such a role, we designed a cohort study whose novelty resides in the classification of products not only according to the source of FVIII (plasmatic, pd, or recombinant, r) but also to their degree of purity (expressed as specific activity).

PATIENTS/METHODS

Treatment data up to inhibitor development or 150 exposure days were collected in 377 patients with hemophilia A.

RESULTS

Inhibitors developed in 111 patients (29%; 96 high-responders, 25%). The cumulative incidence was progressively higher from patients treated with low/intermediate-purity pdFVIII compared with those treated with high-purity pd and rFVIII. The adjusted hazard ratio of inhibitor development was 4.9 with rFVIII and 2.0 with high-purity pdFVIII (95% CI, 2.9-8.3 and 1.1-4.0), taking as reference low/intermediate-purity pdFVIII. There was no difference in the frequency of inhibitor testing between treatment groups. Sensitivity analyses (in patients who never switched product type, previously untreated patients, those treated on-demand and those with high-risk F8 mutations) confirmed an increased inhibitor risk with rFVIII and high-purity pdFVIII.

CONCLUSIONS

This study shows that the degree of purity of FVIII products influences inhibitor development independently from other risk factors, and emphasizes that differences exist within pdFVIII products.

Human recombinant activated factor VII for upper gastrointestinal bleeding in patients with liver diseases

BACKGROUND

Mortality from upper gastrointestinal bleeding in patients with liver disease is high. Recombinant human activated factor VII (rHuFVIIa) has been suggested for patients with liver disease and upper gastrointestinal bleeding.

OBJECTIVES

To assess the beneficial and harmful effects of rHuFVIIa in patients with liver disease and upper gastrointestinal bleeding.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register (December 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 4, 2011), MEDLINE (1948 to December 2011), EMBASE (1980 to December 2011), Science Citation Index Expanded (1900 to December 2011), and LILACS (December 2011). We sought additional randomised trials from the reference lists of the trials and reviews identified through the electronic searches.

SELECTION CRITERIA

Randomised clinical trials.

DATA COLLECTION AND ANALYSIS

Outcome data from randomised clinical trials were extracted and were presented using random-effects model meta-analyses. Data on the risk of bias in the included trials were also extracted.

MAIN RESULTS

We included two trials with 493 randomised participants with various Child-Pugh scores. The trials had a low risk of bias. The rHuFVIIa administration did not reduce the risk of mortality within five days (21/288 (7.3%) versus 15/205 (7.3%); risk ratio (RR) 0.88, 95% confidence interval (CI) 0.48 to 1.64, I(2) = 49%) and within 42 days (5/286 (1.7%) versus 36/205 (17.6%); RR 1.01, 95% CI 0.55 to 1.87, I(2) = 55%) when compared with placebo. Trial sequential analysis demonstrated that there is sufficient evidence to exclude that rHuFVIIa decreases mortality by 80%, but there is insufficient evidence to exclude smaller effects. The rHuFVIIa did not increase the risk of adverse events by number of patients (218/297 (74%) and 164/210 (78%); RR 0.94, 95% CI 0.84 to 1.04, I(2) = 1%), serious adverse events by adverse events reported (164/590 (28%) versus 123/443 (28%); RR 0.91, 95% CI 0.75 to 1.11, I(2) = 0%), and thromboembolic adverse events (16/297 (5.4%) versus 14/210 (6.7%); RR 0.80, 95% CI 0.40 to 1.60, I(2) = 0%) when compared with placebo.

AUTHORS' CONCLUSIONS

We found no evidence to support or reject the administration of rHuFVIIa for patients with liver disease and upper gastrointestinal bleeding. Further adequately powered randomised clinical trials are needed in order to evaluate the proper role of rHuFVIIa for treating upper gastrointestinal bleeding in patients with liver disease. Although the results are based on trials with low risk of bias, the heterogeneity and the small sample size result in rather large confidence intervals that cannot exclude the possibility that the intervention has some beneficial or harmful effect. Further trials with alow risk of bias are required to make more confident conclusions about the effects of the intervention.

A randomized comparison of two prophylaxis regimens and a paired comparison of on-demand and prophylaxis treatments in hemophilia A management

BACKGROUND

Prophylaxis with factor (F)VIII is considered the optimal treatment for managing hemophilia A patients without inhibitors.

OBJECTIVES

To compare the efficacy of two prophylaxis regimens (primary outcome) and of on-demand and prophylaxis treatments (secondary outcome), and to continue the evaluation of immunogenicity and overall safety of the ADVATE Antihemophilic Factor (Recombinant), Plasma/Albumin Free Method (rAHF-PFM).

PATIENTS/METHODS

Previously on-demand-treated patients aged 7-59 years (n = 66) with FVIII levels ≤ 2% received 6 months of on-demand treatment and then were randomized to 12 months of either standard (20-40 IU kg(-1) every other day) or pharmacokinetic (PK)-tailored (20-80 IU kg(-1) every third day) prophylaxis, both regimens intended to maintain FVIII trough levels at or above 1%. Efficacy was evaluated in terms of annualized bleeding rates (ABRs). As subjects were first treated on-demand and then on prophylaxis, statistical comparisons between these treatments were paired.

RESULTS

Twenty-two (33.3%) subjects on prophylaxis experienced no bleeding episodes, whereas none treated on-demand were free from an episode of bleeding. ABRs for the two prophylaxis regimens were comparable, whereas differences between on-demand and either prophylaxis were statistically significant (P < 0.0001): median (interquartile range [IQR]) ABRs were 43.9 (21.9), 1.0 (3.5), 2.0 (6.9) and 1.1 (4.9) during on-demand treatment, standard, PK-tailored and any prophylaxis, respectively. There were no differences in FVIII consumption or adverse event rates between prophylaxis regimens. No subject developed FVIII inhibitors.

CONCLUSIONS

The present study demonstrates comparable safety and effectiveness for two prophylaxis regimens and that prophylaxis significantly reduces bleeding compared with on-demand treatment. PK-tailored prophylaxis offers an alternative to standard prophylaxis for the prevention of bleeding.

Efficacy and safety of human urinary kallidinogenase injection for acute ischemic stroke: a systematic review

OBJECTIVE

To assess the efficacy and safety of human urinary kallidinogenase injection (HUK) in treating patients with acute ischemic stroke.

METHODS

We searched the Chinese Stroke Trials Register, the Cochrane Stroke Group Trials Register, CENTRAL, Medline, EMBASE, the China Biological Medicine Database(CBM), and the China National Knowledge Infrastructure (CNKI), which were all last searched October 2010. Randomized controlled trials (RCTs) about HUK for patients with acute ischemic stroke were included. The quality of each trial was assessed using the Cochrane Reviewers' Handbook 5.0.2.

RESULTS

Twenty-four trials involving 2433 patients were included. Only two trials reported death or dependence at the end of three months follow up. In those trials, HUK reduced death or dependency comparing to the control group (relative ratio (RR) = 0.69, 95% CI 0.55 to 0.86). Twenty trials (2117 patients) reported the proportion of patients with marked neurological improvement after treatment. Meta analysis showed the HUK-treated group had more neurological improvement than did the control group (RR = 1.56, 95% CI 1.44 to 1.70). Fifteen trials reported adverse events, of which transient hypotension was most common (1.5%-5.1%). Non-fatal intracerebral hemorrhage was detected in seven patients, but the difference between the treatment and control groups was not significant (RR = 1.82, 95% CI 0.34 to 9.61). Deaths occurred in both the HUK group (0.4%) and the control group (1.1%), with no significant difference for this outcome (RR = 0.6, 95% CI 0.09 to 3.92). No trial assessed quality of life.

CONCLUSIONS

Available evidence suggests that HUK injection reduces neurological impairment after acute ischemic stroke and improves long-term outcomes, though a few patients suffered from transient hypotension. Further high-quality, large scale randomized trials are needed to confirm these results.

Reversibility of the anti-FXa activity of idrabiotaparinux (biotinylated idraparinux) by intravenous avidin infusion

BACKGROUND

Idraparinux is an inhibitor of activated factor X (FXa) with a long half-life allowing once-weekly dosing. Idrabiotaparinux is a biotinylated version of idraparinux; its activity can be reversed with avidin.

OBJECTIVE

To investigate the tolerability, safety and pharmacodynamics of avidin in healthy subjects and patients with deep vein thrombosis (DVT) receiving idrabiotaparinux.

PATIENTS AND METHODS

In a placebo-controlled, randomized, double-blind Phase I study, 41 healthy males received subcutaneous idrabiotaparinux before being randomized to a 30-min intravenous avidin infusion or placebo. Idrabiotaparinux plus avidin were re-administered 10-14 months later in eight subjects. In addition, in a prospective substudy of the Phase III EQUINOX trial, 55 patients who received weekly idrabiotaparinux for 6 months were randomized to receive either 100 mg avidin (n = 33) or placebo (n = 22). The primary activity outcome was anti-FXa activity calculated immediately before and after avidin infusion. Adverse events were recorded to assess safety and tolerability.

RESULTS

Avidin rapidly reversed the anti-FXa activity of idrabiotaparinux, ranging from 66.1 to 90.3% in healthy subjects and from 67 to 97% (mean 78%) in DVT patients. Avidin was well tolerated, with a similar nature and frequency of adverse events to placebo. No venous thromboembolism recurrence occurred in the 3-month post-avidin infusion.

CONCLUSION

A 30-min intravenous infusion of avidin 100 mg is well tolerated, safe, and offers immediate and specific reversibility both after single and repeated doses of idrabiotaparinux in healthy subjects, and in DVT patients following a 6-month treatment period.

Efficacy and safety of secondary prophylactic vs. on-demand sucrose-formulated recombinant factor VIII treatment in adults with severe hemophilia A: results from a 13-month crossover study

BACKGROUND

Hemarthroses in severe hemophilia precipitate physical, psychosocial and financial difficulties.

OBJECTIVE

To compare the effects of secondary prophylaxis with on-demand sucrose-formulated recombinant factor VIII (rFVIII-FS) therapy in severe hemophilia A.

PATIENTS AND METHODS

This open-label study included patients aged 30-45 years with factor VIII (FVIII) coagulant activity < 1 IU dL(-1) who were using on-demand FVIII treatment. Patients were treated with rFVIII-FS on demand for 6 months, followed by 7 months prophylaxis (20-40 IU kg(-1), three times per week, with the first month considered a run-in). The primary endpoint was the number of hemarthroses.

RESULTS

Twenty patients were enrolled (n = 19 completed); the mean age was 36.4 years, and 16 had target joints. The median (25-75%) number of joint bleeds decreased significantly with prophylaxis [0 (0-3)] vs. on-demand [15 (11-26); P < 0.001] therapy. The number of all bleeds was 0 (0-3) vs. 20.5 (14-37; P < 0.001), respectively. Median (range) total Gilbert scores improved after prophylaxis [18 (3-39)] compared with on-demand [25 (4-46)] therapy, predominantly reflecting the improved bleeding score. Median time from last prophylactic infusion to bleed was 2 days; 82.5% of bleeds occurred 2-3 days after the last infusion. Median 48-h and 72-h FVIII trough levels measured during months 10 and 13 were consistently > 6 and > 4 IU dL(-1), respectively. Treatment was well tolerated, and no inhibitor formation was observed.

CONCLUSION

Secondary prophylaxis with rFVIII-FS significantly reduced the frequency of hemarthroses compared with on-demand therapy in adult patients with severe hemophilia A.

[Personification of the standard treatment of patients with hemophilia A (results of a multicenter Russian open-labeled prospective study evaluating the use of haemoctin)]

AIM

To evaluate the clinical efficiency, tolerability, safety, and immunogenicity of replacement therapy with haemoctin SDH (Biotest Pharma GmbH, Germany) in pretreated patients with hemophilia A (HA).

SUBJECTS AND METHODS

The pretreated patients (n = 140) with varying GA from 12 regions of the Russian Federation received haemoctin replacement therapy (for prophylaxis and if needed) during a year. The levels of coagulation factor VIII, its inhibitor, HIV-1/HIV-2, the markers of hepatic and renal diseases, clinical blood test were determined and a virological study was made thrice during this period at an interval of 6 months. The therapy was considered to be effective if the pain syndrome regressed within 24 hours after the last administration of the drug and/or bleeding stopped. The results of a one-year follow-up of 106 patients receiving haemoctin monotherapy were analyzed.

RESULTS

The history data suggest that there are problems in the diagnosis of hereditary coagulopathies (the mean age of diagnosis verification of 3.5 years; no family history data in 67% of cases), there is a need for the guaranteed provision of patients with adequate quantities of the drug due to the fact that a third of patients had life-threatening bleedings/hemorrhages and that the patients (46%) need additional examination and treatment for comorbidity according to the standards of therapy. Compliance of haemoctin doses and regimens with their timely individual correction ensures a 3-fold reduction on average in the incidence of the hemorrhagic syndrome, an increase in quality of life, and a decrease in the frequency of analgesic use (from 21% to 0). Treatment is satisfactorily tolerated. There is evidence for the safety and low immunogenicity of the drug.

CONCLUSION

To enhance the efficiency of therapeutic-and-prophylactic care to patients with GA and to optimize their quality of life, a personification approach to treatment is recommended, by individually choosing drugs, their doses and regimens.

Acute myocardial infarction in a patient with hemophilia A and factor V Leiden mutation

Factor VIII:C, epsilon amino-caproic acid or tranexamic acid are prophylactic agents used in preventing hemorrhage pre-operatively in patients with hemophilia A. Although hemophilia A seems to be a factor that avoids the development of acute myocardial infarction (AMI) as it tends to be associated with increased bleeding, it should be kept in mind that prothrombotic agents used pre-operatively for prophylaxis may increase the risk for AMI in the presence of the factor V Leiden mutation. In this report, we discuss the development of AMI following the use of recombinant factor VIII and tranexamic acid for prophylaxis in a patient with known hemophilia before a tooth extraction in conjunction with the relevant literature.