RESUMO
INTRODUCTION: Haemophilia A is a rare bleeding disorder caused by defects in coagulation factor VIII (FVIII). Damoctocog alfa pegol (BAY 94-9027, Jivi, Bayer, Germany) is a site-specifically PEGylated, extended-half-life, recombinant FVIII, approved for use in previously treated patients (PTPs) aged ≥12 years with haemophilia A. However, a real-world evidence regarding routine clinical use of damoctocog alfa pegol is limited. METHODS AND ANALYSIS: HEM-POWR is a multinational, multicentre, non-interventional, prospective, postmarketing cohort study evaluating the effectiveness and safety of real-world treatment with damoctocog alfa pegol. Estimated enrolment is ≥200 PTPs with haemophilia A, receiving damoctocog alfa pegol (on-demand, prophylaxis or intermittent prophylaxis (as per local label)), observed for 36 months. Primary outcomes are total bleeding events and annualised bleeding rate; secondary outcomes include long-term safety, joint health, pharmacokinetics, patient-reported outcomes (PROs) from validated questionnaires and perioperative haemostasis. Where applicable, reasons for switching to damoctocog alfa pegol, choice of treatment regimen and dose will also be captured. Exploratory and descriptive statistical analyses will be performed, and will be stratified by parameters including, but not limited to, prophylaxis regimen and haemophilia severity. Patients can record bleeds and consumption in electronic (e) Diaries, ePROs, and can access non-promotional study information (videos explaining study procedures) via an online patient portal. Optionally, patients can enrol in the LIFE-ACTIVE substudy designed to investigate the relationship between activity (measured by the ActiGraph CP Insight watch) and effectiveness parameters collected from HEM-POWR. ETHICS AND DISSEMINATION: Study approval was obtained by local independent ethics committees and authorities in participating study centres across Europe, the Americas and Asia. Informed consent from patients or their legal representative is a requirement for participation. The study results will be submitted for publication in a peer-reviewed scientific journal and presented at scientific conferences. TRIAL REGISTRATION NUMBERS: NCT03932201, EUPAS26416. PROTOCOL VERSION AND DATE: V.1.2, 27 September 2019.
Assuntos
Hemofilia A , Estudos de Coortes , Meia-Vida , Hemofilia A/tratamento farmacológico , Humanos , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: People with hemophilia A or B with inhibitors are at high risk of bleeding complications. Infusion of bypassing agents, such as recombinant activated FVII (rFVIIa) and plasma-derived activated prothrombin complex concentrate, are suggested as alternative therapies to factor VIII (haemophilia A) or IX (haemophilia B) for individuals who no longer respond to these treatments because they develop inhibitory antibodies. The ultimate goal of treatment is to preserve the individual's joints, otherwise destroyed by recurrent bleeds. OBJECTIVES: To assess the effects of bypassing agent prophylaxis to prevent bleeding in people with hemophilia A or B and inhibitors. SEARCH METHODS: We searched for relevant studies from the Cystic Fibrosis and Genetic Disorders Group's Coagulopathies Trials Register, comprising of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also searched trial registries (16 February 2017) and bibliographic references of retrieved studies were reviewed for potential articles to be included in the review.Date of the last search of the Cochrane Cystic Fibrosis and Genetic Disorders Coagulopathies Trials Register: 12 December 2016. SELECTION CRITERIA: We included randomized and quasi-randomized controlled studies (cross-over or parallel design) evaluating the effect of prophylaxis treatment with bypassing agents compared with on-demand treatment, or studies evaluating the effects of high-dose compared with low-dose prophylaxis in males of any age with hemophilia with inhibitors. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies and extracted data and assessed the risk of bias according to standard Cochrane criteria. They assessed the quality of the evidence using the GRADE criteria. MAIN RESULTS: We included four randomized studies (duration 7 to 15 months) involving 116 males. Risk of bias was judged to be high in two studies due to the open-label study design and in one study due to attrition bias.Two studies compared on-demand treatment to prophylaxis with bypassing agents. In one study (34 males) prophylaxis significantly reduced mean overall bleeding rates, MD - 7.27 (95% CI -9.92 to -4.62) (low quality evidence), mean number of overall bleeding events per month, MD -1.10 (95% CI -1.54 to -0.66), mean number of hemarthrosis, MD -6.60 (95% CI -9.32 to -3.88) (low quality evidence) and mean number of joints that had hemarthrosis, MD -0.90 (95% CI -1.36 to -0.44). The meta-analysis did not conclusively demonstrate significant benefit of prophylaxis on health-related quality of life as measured by Haem-A-QoL score, EQ-5D total score and utility score, EQ-5D VAS and SF-36 physical summary and mental summary score (low quality evidence for all health-related quality of life analyses).The remaining two studies compared dose regimens. The results from one study (22 males) did not conclusively demonstrate benefit or harm of high-dose versus low-dose recombinant activated factor VIIa (rFVIIa) as a prophylaxis for overall bleeding rate, MD -0.82 (95% CI -2.27 to 0.63) (moderate quality evidence), target joint bleeding rate, MD -3.20 (95% CI -7.23 to 0.83) (moderate quality evidence) and serious adverse events, RR 9.00 (95% CI, 0.54 to 149.50) (moderate quality evidence).The overall quality of evidence was moderate to low due to imprecision from limited information provided by studies with small sample sizes and incomplete outcome data in one study. AUTHORS' CONCLUSIONS: The evidence suggests that prophylaxis with bypassing agents may be effective in reducing bleeding in males with hemophilia with inhibitors. However, there is a lack of evidence for the superiority of one agent over the other or for the optimum dosage regimen. Further studies are needed to evaluate the benefits and harms of prophylaxis treatment on health-related quality of life, as well as the effects of dose of bypassing agents on the outcomes.