Coagadex is a high‐purity plasma‐derived factor X concentrate (pdFX) developed to treat hereditary factor X deficiency (FXD).
Evaluate the efficacy and safety of pdFX administered to patients with ...hereditary FXD.
This was an open‐label, multicenter, retrospective analysis of patients receiving pdFX for compassionate use. Efficacy end points included treatments administered, the number and treatment of bleeds, and investigator assessments. Adverse drug reactions (ADRs) were monitored.
Fifteen patients were included: seven received routine prophylaxis, seven received on‐demand treatment, and one alternated. Most were aged ≥12 years (n = 13) and had severe hereditary FXD (n = 12). The median follow‐up time was 19.2 months (range, 3.5‐48.8). The number of infusions per patient per month was higher for the routine prophylaxis group (median range, 5.4 1.4‐10.1) than for the on‐demand group (0.8 0.1‐2.3), as was the dose per infusion (27.9 21.9‐53.6 IU/kg vs 20.0 13.6‐27.7 IU/kg). Patients experienced 88 bleeds (34 minor, 7 major, 47 unclassified). The monthly bleed rate per patient was 0.04 in the routine prophylaxis group (based on 17 bleeds in four patients) and 0.8 in the on‐demand group (based on 71 bleeds in eight patients). pdFX was used to treat 79 bleeds and was rated effective in all instances. In an overall assessment, investigators rated pdFX as excellent for 14 patients (93.3%) and good for 1 patient (6.3%). No ADRs or safety concerns were reported.
This analysis supports the use of pdFX as a safe, effective treatment for hereditary FXD. Routine prophylaxis with pdFX may reduce bleed frequency.
Despite clinical remission and normal platelet counts, congenital TTP (cTTP) is associated with non‐overt symptoms. Prophylactic ADAMTS13 replacement therapy such as plasma infusion (PI) prevents ...acute episodes and improves symptomatology. There is no current method to investigate disease severity or monitor the impact of treatment. We utilize a dynamic high shear flow assay to further understand disease pathophysiology and determine the impact of cTTP on symptomatology and therapy, despite normal platelet counts. Whole blood, under high shear, was run over collagen‐coated channels, causing platelet adhesion to von Willebrand factor (VWF) multimers. The resulting surface coverage by platelet‐VWF thrombus was assessed. The normal range was 6–39% in 50 controls. Twenty‐two cTTP patients with normal platelet counts were evaluated. Median pre‐treatment surface coverage was 89%, and PI reduced coverage to a median of 44% (p = 0.0005). Patients taking antiplatelets had further reduced coverage when combined with PI and improved non‐overt symptoms such as headache, lethargy, and abdominal pain in 100% of patients compared to 74% with PI alone (p = 0.046). We use a dynamic assay to report increased in vitro platelet adhesion and aggregation and additionally demonstrate significantly decreased thrombi following PI, with levels in the normal range levels achieved in patients taking additional antiplatelet therapy.
Summary
Severe platelet function defects are rare disorders that require expertise in diagnosis and management. Therefore patients with such disorders should be referred to and managed in centres ...with the full laboratory repertoire of tests and clinical support necessary to optimise their quality of care. The aim of this review is to discuss the management of these patients in various clinical situations including surgical intervention.
Introduction
FVIII inhibitor development is the greatest challenge when treating previously untreated patients (PUPs) with hemophilia A (HA). The SIPPET study reported a cumulative inhibitor ...incidence of 44.5% (28.4% high-titre) in PUPs treated with recombinant FVIII (rFVIII) products produced in hamster cell lines and 26.8% (18.6% high-titre) with plasma-derived FVIII products containing von Willebrand factor (pdFVIII/VWF). Simoctocog alfa (Nuwiq®) is a 4th generation rFVIII produced in a human cell line without chemical modification or protein fusion. The NuProtect study assessed the immunogenicity, efficacy and safety of simoctocog alfa in PUPs with severe HA. A prespecified interim analysis was published with data up to 20 and 50 EDs (Haemophilia 2018; 24:211) and here we report the final results.
Methods
NuProtect was a prospective, multinational, open-label, non-controlled, phase III study. True PUPs (no prior FVIII treatment) with severe HA of any age and ethnicity were to be enrolled and treated for 100 exposure days (EDs) or a maximum of 5 years with simoctocog alfa for prophylaxis, on-demand treatment, treatment of breakthrough bleeding episodes (BEs) and surgical prophylaxis. Type of treatment and dose were determined by the investigator. Inhibitor screening (modified Bethesda assay) was performed at screening, every 3-4 EDs until ED20, then every 10-12 EDs or at least every 3 months, at completion, and if inhibitor development was suspected. Inhibitor levels of ≥0.6 to <5 Bethesda units BU/mL were defined as low-titer and ≥5 BU/mL as high-titer. Cumulative inhibitor incidence (primary endpoint) and 95% confidence intervals (CIs) were calculated (Kaplan-Meier). Efficacy endpoints (inhibitor-free periods) included the annualized bleeding rate (ABR) during prophylaxis and efficacy in treating BEs/surgical prophylaxis (4-point objective scales: excellent, good successful; moderate or none). Adverse events (AEs) were monitored throughout the study.
Results
Of 108 subjects consented, 105 PUPs, median age of 12 months (range 0-146) at ED1 were evaluable for inhibitor development. They were treated for a median of 101 EDs (range 1-1164), with 96 patients treated for ≥100 EDs (or until inhibitor development, including 5 patients with 97-99 EDs). The majority of patients with available genetic data had null F8 gene mutations (90/102 88.2%) and 13 (12.0%) had a family history of inhibitors. Cumulative inhibitor incidence was 17.6% (95% CI: 10.0%, 25.3%) for high-titre inhibitors and 27.9% (95% CI: 19.1%, 36.7%) for all inhibitors (Figure 1). No PUPs with non-null F8 mutations developed inhibitors. In 50 PUPs on continuous prophylaxis for ≥6 months, the mean (SD) ABR was 0.54 (1.07) median 0 for spontaneous BEs and 3.61 (3.82) median 2.53 for all BEs. The treatment of BEs was successful in 92.9% (747/804) of rated BEs in 85 patients with treated BEs and 91.9% of BEs were controlled with 1 or 2 infusions. Surgical prophylaxis was successful for 94.7% (18/19) of rated procedures and moderate for 5.3% (1/19). Excluding inhibitors, only one (0.9%) patient had an AE classified as serious by the investigator (hospitalization due to a mild rash that resolved with anti-histamine treatment).
Conclusions
Simoctocog alfa had a similar inhibitor incidence in PUPs with severe HA as pdFVIII/VWF products in SIPPET. No inhibitors occurred in PUPs with non-null F8 mutations. Simoctocog alfa had a median spontaneous ABR of 0 during prophylaxis and was successful in the treatment of 92.9% of BEs and in 94.7% of surgical procedures. These results complement results in previously treated patients (PTPs) and support the use of simoctocog alfa in the prevention and treatment of BEs in PUPs and PTPs.
References
Liesner R, et al. Haemophilia 2018; 24: 211-20.
Display omitted
Liesner:Octapharma, Bayer, Takeda, Novo Nordisk, CSL Behring, Roche: Research Funding; Octapharma, SOBI, Novo Nordisk: Speakers Bureau; Octapharma, Bayer, Takeda: Consultancy. Neufeld:Octapharma, Shire Pharmaceuticals (Baxalta), Novo Nordisk, Celgene, NHLBI/NIH: Research Funding; Octapharma, Agios, Acceleron, Grifols, Pfizer, CSL Behring, Shire Pharmaceuticals (Baxalta), Novo Nordisk, ApoPharma, Genentech, Novartis, Bayer Healthcare: Consultancy; Octapharma: Other: study investigator, NuProtect study (Octapharma-sponsored).
Summary
The guideline writing group was selected to be representative of UK‐based medical experts. MEDLINE was systematically searched for publications in English up to the Summer of 2010 using key ...words platelet, platelet function testing and platelet aggregometry. Relevant references generated from initial papers and published guidelines/reviews were also examined. Meeting s were not included. The writing group produced the draft guideline, which was subsequently revised and agreed by consensus. Further comment was made by members of the Haemostasis and Thrombosis Task Force of the British Committee for Standards in Haematology. The guideline was then reviewed by a sounding board of approximately 40 UK haematologists, the British Committee for Standards in Haematology (BCSH) and the British Society for Haematology Committee and comments incorporated where appropriate. Criteria used to quote levels and grades of evidence are as outlined in appendix 7 of the Procedure for Guidelines Commissioned by the BCSH http://www.bcshguidelines.com/BCSH_PROCESS/EVIDENCE_LEVELS_AND_GRADES_OF_RECOMMENDATION/43_GRADE.html. The objective of this guideline is to provide healthcare professionals with clear guidance on platelet function testing in patients with suspected bleeding disorders. The guidance may not be appropriate to patients receiving antiplatelet therapy and in all cases individual patient circumstances may dictate an alternative approach.
Emicizumab, a bispecific humanized monoclonal antibody, bridges activated factor IX (FIX) and FX to restore the function of missing activated FVIII in hemophilia A. Emicizumab prophylaxis in children ...with hemophilia A and FVIII inhibitors was investigated in a phase 3 trial (HAVEN 2). Participants, previously receiving episodic/prophylactic bypassing agents (BPAs), were treated with subcutaneous emicizumab: 1.5 mg/kg weekly (group A), 3 mg/kg every 2 weeks (group B), or 6 mg/kg every 4 weeks (group C). Pharmacokinetics, safety, and efficacy (including an intraindividual comparison of participants from a noninterventional study) were evaluated. Eighty-five participants aged <12 years were enrolled. In group A (n = 65), the annualized rate of treated bleeding events (ABRs) was 0.3 (95% confidence interval CI, 0.17-0.50), and 77% had no treated bleeding events. Intraindividual comparison of 15 participants who previously took BPA prophylaxis showed that emicizumab prophylaxis reduced the ABR by 99% (95% CI, 97.4-99.4). In groups B (n = 10) and C (n = 10), ABRs were 0.2 (95% CI, 0.03-1.72) and 2.2 (95% CI, 0.69-6.81), respectively. The most frequent adverse events were nasopharyngitis and injection-site reactions; no thrombotic events occurred. Two of 88 participants developed antidrug antibodies (ADAs) with neutralizing potential, that is, associated with decreased emicizumab plasma concentrations: 1 experienced loss of efficacy, and, in the other, ADAs disappeared over time without intervention or breakthrough bleeding. All other participants achieved effective emicizumab plasma concentrations, regardless of the treatment regimen. Emicizumab prophylaxis has been shown to be a highly effective novel medication for children with hemophilia A and inhibitors. This trial was registered at www.clinicaltrials.gov as #NCT02795767.
•Emicizumab prophylaxis achieved substantial efficacy and was well tolerated in children with hemophilia A with FVIII inhibitors.•Emicizumab may offer a new standard of care that reduces treatment burden in young patients with hemophilia A with inhibitors.
Display omitted
Thrombotic thrombocytopenic purpura (TTP) in children is rare and is often thought to be due to congenital ADAMTS13 deficiency. We report seven new cases of noncongenital TTP in children and ...adolescents and perform a review of the literature where ADAMTS13 assays have been performed in paediatric acquired TTP. All new cases were female and the median age was 13 years. Presenting clinical features included bruising/petechiae or bleeding, fever, neurological, and renal impairment. Median Hb and platelet counts on admission were 66 g/l and 10 × 10/l respectively. Two cases had raised Troponin T levels and one had an abnormal ECG. All cases had ADAMTS13 activity less than 5% and an inhibitor to ADAMTS13. The median number of plasma exchange to remission was 22.5. Six cases received rituximab. Three achieved normal ADAMTS13 activity and remain in remission. Two had persistently low ADAMTS13 activity with high anti-ADAMTS13 IgG levels and one of these relapsed. One had moderately reduced levels of ADAMTS13 in remission with no inhibitor, however, a fall in ADAMTS13 activity and increase in anti-ADAMTS13 IgG heralded clinical relapse. The literature review identified 12 acquired cases showing low ADAMTS13 activity and inhibition of ADAMTS13 (in 95%). In children and adolescents TTP may be due to acquired deficiency of ADAMTS13, associated with an inhibitor/Anti-ADAMTS13 IgG antibodies. Treatment of acquired disease requires PEX and usually immunosuppressive treatment. Rituximab appears to be an effective adjunctive treatment modality.
Summary
Venous thrombo‐embolism (VTE) is increasingly recognized in paediatric practice. Few clinical trials have been performed in this area in children and management is largely extrapolated from ...adult practice where there is a considerable evidence base. This is likely to be unsatisfactory for a number of reasons. Firstly, there are significant differences in epidemiology and potential differences in the mechanisms for VTE in this age group. Secondly, many aspects of haemostasis are age‐dependant, which has implications for the use of anticoagulants in the paediatric population. Thirdly, there are very limited data available on the safety and efficacy of anticoagulants to manage specific indications in paediatric practice, often with limited paediatric formulations available. In addition, children may survive for a prolonged period following these events so that long‐term consequences may be highly significant in this age group. The aim of this guideline is to provide a rational basis for the investigation and management of children aged 1 month–16 years with VTE, including cerebral venous thrombosis (CVT). The guideline is targeted at healthcare professionals involved in the management of children and adolescents with VTE, particularly paediatric haematologists.
Summary
Thrombotic thrombocytopenic purpura (TTP) is an acute, rare, life‐threatening disorder. This report presents the South East (SE) England registry for TTP, from April 2002 to December 2006, ...which included 176 patients and 236 acute episodes; 75% of patients were female and 25% were male, overall median age at presentation was 42 years. Mortality was 8·5%, most cases died before treatment was instigated. The main ethnic groups were Caucasian (64%) and Afro Caribbean (27%). Seventy‐seven percent of cases were idiopathic, 5% were congenital and the remaining cases had a defined precipitant. Neurological features were the most prevalent, but cardiac involvement accounted for 42% of presenting features. The overall median number of plasma exchanges (PEXs) to remission was 15; between April 2002 and December 2003, the median number of PEXs was 19 and it was 12 between January 2004 and December 2006 (P < 0·0001). In the latter period, adjuvant therapies were reduced, but Rituximab was increased. ADAMTS 13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity was <10% in 74% and 95% of these cases had positive IgG antibodies to ADAMTS 13. Renal impairment and delayed normalisation of platelet count were the main differences between idiopathic and secondary TTP.
Introduction and Objective: Inhibitors to coagulation factor VIII (FVIII) are the most serious complication of haemophilia A treatment. Previously untreated patients (PUPs) are at the greatest risk ...of inhibitors, which generally occur within the first 20 exposure days (ED) to FVIII. Immune tolerance induction (ITI) is the only clinically proven strategy for eradication of inhibitors. We present a case series of six PUPs with severe haemophilia A and inhibitors who underwent ITI with simoctocog alfa (Nuwiq®), a 4th generation human cell-line-derived recombinant FVIII approved for treatment of haemophilia A.
Materials and Methods: Six male PUPs with severe haemophilia A who developed FVIII inhibitors after treatment with simoctocog alfa were started on ITI with simoctocog alfa. Primarily, we assessed the success of simoctocog alfa in patients with inhibitors. Success of ITI was determined based on undetectable inhibitor titre (< 0.6 BU/ml), FVIII recovery ≥ 66% and half-life ≥ 6 hours. Secondary objectives were to assess bleeding rate, tolerability and safety in patients with inhibitors treated with simoctocog alfa ITI.
Results: The age of the patients at the start of ITI ranged from 8 to 186 months. Four of the patients were Caucasian, and two were African. All patients had a F8 mutation associated with high risk of ITI failure and two patients had an additional risk factor for ITI failure. The number of EDs prior to inhibitor development ranged from 9 to 33, and the peak inhibitor titre ranged from 0.9 to 114 BU. For ITI, five patients were treated with 100 IU/kg simoctocog alfa daily, and one with 90 IU/kg every other day. One patient achieved complete tolerisation and is now on prophylaxis at normal doses, having achieved an undetectable inhibitor titre after 9 months. This was despite an inhibitor titre ≥ 10 BU/mL at ITI start, which is considered a poor prognosis factor for ITI success. Three other patients achieved an undetectable inhibitor titre after 1, 6 and 18 months of ITI, and FVIII recovery has normalised but half-life remains short and they are on weaning doses as the half-life extends. One patient discontinued ITI with simoctocog alfa after 15 months due to an increasing inhibitor level. This patient was 15 years old at ITI start, and older age is associated with poor ITI outcome. Additionally, his haemophilia A was untreated for 15 years, during which time he developed severe arthropathy. One patient, who started ITI 3 months ago, has an ongoing inhibitor titre and continues on ITI with simoctocog alfa.
Conclusions: In a case series of six patients treated with simoctocog alfa for ITI, who all had poor prognosis factors for ITI success, four patients (67%) to date have achieved an undetectable inhibitor titre. These data suggest that ITI with simoctocog alfa may be an effective treatment approach in haemophilia A patients with inhibitors.
Khair:Shire, SOBI, Pfizer, Roche, Novo Nordisk, Octapharma: Speakers Bureau; shire, SOBI, Pfizer, Roche: Research Funding. Liesner:Roche: Research Funding; Novo Nordisk: Research Funding, Speakers Bureau; Baxalta: Consultancy, Research Funding; Bayer: Consultancy, Research Funding; Octapharma: Consultancy, Other: Clinical study investigator for NuProtect Study (Octapharma sponsored), Research Funding, Speakers Bureau; Sobi: Speakers Bureau. Belyanskaya:Octapharma AG: Employment.
PDF
