Prophylaxis in haemophilia: a double-blind controlled trial. Twice weekly prophylactic therapy in haemophilia A. Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia. Evaluation of prophylactic replacement therapy in haemophilia B. A randomized clinical trial of prophylaxis in children with hemophilia A (the ESPRIT Study).
A double-blind controlled trial of prophylactic factor VIII therapy has been carried out on nine severe haemophiliacs at the Lord Mayor Treloar College. Infusions were given once weekly and calculated to give a post-infusion plasma concentration of at least 0.25 I.U./ml of factor VIII. This regime reduced the overall bleeding frequency by 15%. The bleeding frequency in the first 3 days post-infusion was reduced by 66%. A moderate overall reduction in morbidity was also achieved. It is calculated that to reduce the incidence of bleeding in severe haemophiliacs by 15% would require a 73% increased usage of therapeutic materials. More than twice this amount of material is likely to be needed to reduce the bleeding frequency of the same group by 66%. Factor VIII-containing materials were administered to four severely affected haemophiliacs twice weekly in doses calculated to raise the factor VIII level to either 15% or 30% of average normal. The pooled results from those patients with statistically similar baseline bleeding frequencies showed a significant reduction in bleeding frequency on both doses in the first 48 hours. The 30% dose produced a more significant reduction than the 15% dose in the first 24 hours, but there was no significant difference between the two doses in the second 24 hours. It appears that to reduce the bleeding frequency of severely affected haemophiliacs by 60% would require a two-and-a-half-fold increase in therapeutic materials. A 90% reduction would need nine times the amount of material currently in use. Effective ways to prevent arthropathy in severe hemophilia are unknown.
                We randomly assigned young boys with severe hemophilia A to regular infusions of recombinant factor VIII (prophylaxis) or to an enhanced episodic infusion schedule of at least three doses totaling a minimum of 80 IU of factor VIII per kilogram of body weight at the time of a joint hemorrhage. The primary outcome was the incidence of bone or cartilage damage as detected in index joints (ankles, knees, and elbows) by radiography or magnetic resonance imaging (MRI).
                Sixty-five boys younger than 30 months of age were randomly assigned to prophylaxis (32 boys) or enhanced episodic therapy (33 boys). When the boys reached 6 years of age, 93% of those in the prophylaxis group and 55% of those in the episodic-therapy group were considered to have normal index-joint structure on MRI (P=0.006). The relative risk of MRI-detected joint damage with episodic therapy as compared with prophylaxis was 6.1 (95% confidence interval, 1.5 to 24.4). The mean annual numbers of joint and total hemorrhages were higher at study exit in the episodic-therapy group than in the prophylaxis group (P<0.001 for both comparisons). High titers of inhibitors of factor VIII developed in two boys who received prophylaxis; three boys in the episodic-therapy group had a life-threatening hemorrhage. Hospitalizations and infections associated with central-catheter placement did not differ significantly between the two groups.
                Prophylaxis with recombinant factor VIII can prevent joint damage and decrease the frequency of joint and other hemorrhages in young boys with severe hemophilia A. (ClinicalTrials.gov number, NCT00207597 [ClinicalTrials.gov].).
                Copyright 2007 Massachusetts Medical Society. Prophylaxis replacement therapy has been assessed for a period of 12 months in 10 patients with severe haemophilia B showing a high incidence of spontaneous bleeding episodes. Two different schedules of administration of a freeze-dried factor IX concentrate were randomly evaluated: according to scheme A, 7.5 U/kg were administrated biweekly, whereas scheme B was based on the weekly infusion of 15 U/kg. On prophylaxis the frequency of bleeding episodes was significantly reduced (P less than 0.005) when compared with that observed in one-year period preceding the trial. Biweekly infusions were superior to weekly infusion (P less than 0.01), and the benefit appeared to be related to the higher number of days in which measurable levels of factor IX were attained in plasma. Range of motion, which was redeced at the start of the trial in 26 joints, was found to have improved in 23. Favourable changes of the joint radiological picture were observed in 6 cases. Hepatitis and factor IX inhibitors did not develop during the trial period. Side effects were rare and mild. Prevention of arthropathy is a major goal of hemophilia treatment. While studies in adults have demonstrated an impact of prophylaxis on the incidence of joint bleeds and patients' well-being in terms of improved quality of life (QoL), it is unclear whether or not prophylaxis influences the outcome and perception of well- of children with hemophilia.
                This randomized controlled study compared the efficacy of prophylaxis with episodic therapy in preventing hemarthroses and image-proven joint damage in children with severe hemophilia A (factor VIII <1%) over a 10-year time period.
                Forty-five children with severe hemophilia A, aged 1-7 years (median 4), with negative clinical-radiologic joint score at entry and at least one bleed during the previous 6 months, were consecutively randomized to prophylaxis with recombinant factor VIII (25 IU kg(-1) 3 × week) or episodic therapy with ≥25 IU kg(-1) every 12-24 h until complete clinical bleeding resolution. Safety, feasibility, direct costs and QoL were also evaluated.
                Twenty-one children were assigned to prophylaxis, 19 to episodic treatment. Children on prophylaxis had fewer hemarthroses than children on episodic therapy: 0.20 vs. 0.52 events per patient per month (P < 0.02). Plain-film radiology showed signs of arthropathy in six patients on prophylaxis (29%) vs. 14 on episodic treatment (74%) (P < 0.05). Prophylaxis was more effective when started early (≤36 months), with patients having fewer joint bleeds (0.12 joint bleeds per patient per month) and no radiologic signs of arthropathy.
                This randomized trial confirms the efficacy of prophylaxis in preventing bleeds and arthropathy in children with hemophilia, particularly when it is initiated early in life.
                © 2011 International Society on Thrombosis and Haemostasis.
There is strong evidence from randomised controlled trials and observational trials that prophylaxis preserves joint function in children with hemophilia as compared to on-demand treatment. There is insufficient evidence from randomised controlled trials to confirm the observational evidence that prophylaxis decreases bleeding and related complications in patients with existing joint damage. Well-designed randomised controlled trials and prospective observational controlled studies are needed to establish the best prophylactic regimen and to assess the effectiveness of prophylactic clotting factor concentrates in adult patients.