Although immune tolerance induction (ITI) has been used for 30 years to eliminate inhibitors and restore normal factor pharmacokinetics in patients with hemophilia, there is a paucity of scientific ...evidence to guide therapeutic decision-making. In an effort to provide direction for physicians and hemophilia treatment center staff members, an international panel of hemophilia opinion leaders met to develop consensus recommendations for ITI in patients with severe and mild hemophilia A and hemophilia B. These recommendations draw on the available published literature and the collective clinical experience of the group and are rated based on the level of supporting evidence.
Aim
To describe the prevalence and complications in babies ≤2 years with haemophilia.
Methods
We used a standardized collection tool to obtain consented data on eligible babies aged ≤2 years with ...haemophilia enrolled in the Centers for Disease Control and Prevention Universal Data Collection System surveillance project at US Hemophilia Treatment Centers (HTCs).
Results
Of 547 babies, 82% had haemophilia A, and 70% were diagnosed within one month of birth. Diagnosis was prompted by known maternal carrier status (40%), positive family history (23%), bleeding (35%) and unknown 2%; 81% bled during the first two years. The most common events were bleeding (circumcision, soft tissue, oral bleeding) and head injury. There were 46 episodes of intracranial haemorrhage (ICH) in 37 babies (7%): 18 spontaneous, 14 delivery related, 11 traumatic, 2 procedure related and 1 unknown cause. Of the 176 central venous access devices (CVADs) in 148 (27%) babies, there were 137 ports, 22 surgically inserted central catheters and 20 peripherally inserted central catheters. Ports had the lowest complication rates. Inhibitors occurred in 109 (20%) babies who experienced higher rates of ICH (14% vs. 5%; P = 0.002), CVAD placement (61% vs. 19%; P < 0.001) and CVAD complications (44% vs. 26%; P < 0.001). The most common replacement therapy was recombinant clotting factor concentrates.
Conclusion
Bleeding events in haemophilic babies ≤2 years were common; no detectable difference in the rates of ICH by the mode of delivery was noted. Neonatal factor exposure did not affect the inhibitor rates. Minor head trauma, soft tissue and oropharyngeal bleeding were the leading indications for treatment.
Recombinant factor VIIa (rFVIIa: NovoSeven; Novo Nordisk) has proven efficacy in the treatment of haemophilic patients with inhibitors. This prospective, double-blind study compared rFVIIa (35 vs. 90 ...microg/kg) in the initiation and maintenance of haemostasis during and after elective surgery. Patients with inhibitors (FVIII, n = 26; FIX, n = 3) received rFVIIa immediately prior to incision; intraoperatively as needed; every 2 h for the first 48 h; and every 2-6 h for the following 3 days. Haemostasis was evaluated during surgery, at 0, 8, 24 and 48 h and 3, 4 and 5 days after wound closure. After day 5, open-label rFVIIa (90 microg/kg) was available for maintenance. Intraoperative haemostasis was achieved in 28/29 patients. All high-dose patients and 12/15 low dose patients had satisfactory haemostasis during the first 48 h. Twenty-three patients (13/14 high dose) successfully completed the study. Although the 35 microg/kg dose is probably sub-optimal for post-operative management, at least in major procedures, rFVIIa 90 microg/kg is an effective first-line option in surgery for patients with inhibitors.
To assess the safety and efficacy of a fixed dose of recombinant activated factor VII (rFVIIa; NovoSeven) in the home setting for mild to moderately severe joint, muscle; and mucocutaneous bleeding ...episodes in patients with haemophilia A or B with inhibitors.
Multicentre, open-label, single arm, phase III study of one year duration. METHODS; Patients or their caregivers administered up to three doses of rFVIIa (90 microg/kg i.v.) at 3 h intervals within 8 h of the onset of a mild to moderate bleeding episode. Once the subject considered that rFVIIa had been "effective" with regard to haemostasis (after 1-3 injections), one further (maintenance) dose of rFVIIa was administered.
Of 60 patients enrolled, 56 experienced at least one bleed, and 46 completed the one year study. 614 of 877 bleeds (70%) were evaluable according to protocol definitions. Haemostasis was rated as "effective" in 92% (566/614) of evaluable bleeds after a mean of 2.2 injections. For successfully treated episodes, the time from onset of bleeding until administration of the first injection was 1.1+/-2.0 h (mean+/-SD). Twenty-four hours after initial successful response, haemostasis was reported as having been maintained in 95% of cases. Efficacy was comparable for muscle, joint and target joint, and mucocutaneous bleeding episodes. In an intent-to-treat analysis of all 877 bleeding events, efficacy outcomes were equivalent to the evaluable bleeds, with an effective response in 88% of treated episodes. Treatment-related adverse events occurred in 32 (3% of all) bleeding episodes and consisted of re-bleeds/new bleeds in more than 50% (18/32) of these events. A single episode of superficial thrombophlebitis was the only thrombotic complication encountered, and there were no patient withdrawals due to adverse events. Development of FVII(a) antibodies could not be detected, and hypersensitivity reactions to rFVIIa were not reported.
rFVIIa is effective and well tolerated when used in the home setting to treat mild to moderate bleeding episodes in patients with haemophilia A or B with inhibitors.
OBI‐1 is a recombinant B‐domain deleted porcine factor VIII (FVIII). FVIII treatment in those with haemophilia A may be complicated by the development of anti‐FVIII antibodies (inhibitors) leading to ...a failure to respond to treatment with human FVIII. To compare the pharmacokinetics and safety of a single dose of OBI‐1 with Hyate:C in subjects with haemophilia A and inhibitors, subjects were randomized to receive either Hyate:C followed by placebo or placebo followed by OBI‐1 in a double‐blind fashion. FVIII levels were assayed using both a one‐stage coagulation assay (OSCA) and chromogenic assay. Pharmacokinetic parameters for FVIII were calculated for 6/9 subjects randomized; in three subjects baseline anti‐porcine FVIII inhibitors led to a lack of measurable FVIII activity. Mean Cmax appeared higher for OBI‐1 (OSCA: 176.00 U dL−1, standard deviation ± 88.00; chromogenic: 151.00 ± 31.51 U dL−1) than Hyate:C (OSCA: 82.3 ± 19.22 U dL−1; chromogenic: 52.67 ± 13.8 U dL−1). Mean AUC also appeared higher for OBI‐1 (OSCA: 2082.87 ± 1323.43 U h−1dL−1; chromogenic: 1817.28 ± 625.14 U h−1dL−1) than Hyate:C (OSCA: 1177.8 ± 469.49 U h−1dL−1; chromogenic: 707.61 ± 420.05 U h−1dL−1). Two infusion‐related events occurred: one with Hyate:C, one with placebo. Four of five subjects without anti‐porcine FVIII inhibitors at baseline remained porcine FVIII inhibitor negative 29 days after infusion. A single dose of OBI‐1 appears to have higher bioavailability than Hyate:C in subjects with haemophilia A without measurable anti‐porcine FVIII inhibitors, and is well tolerated. These results should be confirmed in a larger phase 2/3 study.
Participants in an international conference on the management of haemophilia patients with inhibitors developed a jointly authored summary of the findings and conclusions of the conference. Current ...knowledge of the genetic and immunologic mechanisms underlying inhibitor development was briefly summarized. Concerning the purported treatment‐related risk factors, conference participants commented on the limitations of the available evidence and the need for more rigorous prospective research in a fully genotyped population. Other clinical considerations discussed included the unproved utility of routine surveillance, the need for assay standardization, the management of acute bleeding and approaches to joint disease prophylaxis and immune tolerance induction (ITI). A number of issues were identified as needing further investigation in larger prospective studies, ideally through international cooperation. Such studies should enrol cohorts that have been scrupulously defined in terms of mutation status and treatment exposure. Finally, conference participants urged their colleagues to participate in the currently ongoing international trials of ITI.
Haemophilia patients with inhibitors characteristically have impaired joint function and reduced health‐related quality of life (HRQoL). This analysis examined whether secondary prophylaxis with ...recombinant activated factor VII (rFVIIa) improves HRQoL vs. conventional on‐demand therapy in patients with haemophilia with inhibitors and frequent bleeds. After a 3‐month preprophylaxis period, 22 patients received daily rFVIIa prophylaxis (90 or 270 μg kg−1) for 3 months, followed by 3 months’ postprophylaxis. Days of hospitalization, absence from school/work and mobility aids requirements were recorded. HRQoL was assessed by EuroQoL (EQ‐5D) questionnaire, visual analogue scale (VAS), derived Time to Trade‐Off (TTO) scores and Quality Adjusted Life Years (QALYs). rFVIIa prophylaxis significantly (P < 0.0001) reduced bleeding frequency vs. prior on‐demand therapy. Hospitalization (5.9% vs. 13.5%; P = 0.0026) and absenteeism from school/work (16.7% vs. 38.7%; P = 0.0127) decreased during prophylaxis; these effects tended to be maintained during postprophylaxis. HRQoL (evaluated by EQ‐5D) tended to improve during and after rFVIIa prophylaxis. Notably, pain decreased and mobility increased in 40.9% and 27.3% of patients, respectively, at the end of the postprophylaxis period vs. preprophylaxis. Median VAS score increased from 66 to 73 (P = 0.048), and TTO scores suggested better HRQoL (0.62 vs. 0.76; P = 0.054) during postprophylaxis than preprophylaxis. Small to moderate changes in effect sizes were reported for VAS and TTO scores. Median QALYs were 0.68 (VAS) and 0.73 (TTO). Reductions in bleeding frequency with secondary rFVIIa prophylaxis were associated with improved HRQoL vs. on‐demand therapy.
Pathogenesis of haemophilic synovitis: clinical aspects HOOTS, W. K.; RODRIGUEZ, N.; BOGGIO, L. ...
Haemophilia : the official journal of the World Federation of Hemophilia,
11/2007, Letnik:
13, Številka:
s3
Journal Article
Recenzirano
Arthropathy remains a major cause of morbidity in patients with haemophilia. Frequent bleeding into the joints leads to joint damage with resultant contractures, joint deformities and arthritis. This ...in turn leads to muscle atrophy, limited physical activity, osteoporosis and disability. Even though several studies of prophylactic factor replacement for persons with severe haemophilia demonstrate improved joint function, this therapy is still not readily available to most people with haemophilia around the world and a universal treatment protocol has not been used. In this article, we discuss key issues in the treatment of severe haemophilia: the optimal timing of initiation and termination of therapy, dosing options and goals of therapy. The options for countries where prophylaxis is not readily available are also discussed. Most studies are small and not randomized making consensus treatment recommendations difficult to formulate. Randomized, clinical trials are needed to provide the answers regarding the optimal treatment of patients with severe haemophilia.
Hemarthrosis is a common manifestation of haemophilia, and joint arthropathy remains a frequent complication. Even though the exact mechanisms related to blood‐induced joint disease have not yet been ...fully elucidated, it is likely that iron deposition in the synovium induces an inflammatory response that causes not only immune system activation but also stimulates angiogenesis. This process ultimately results in cartilage and bone destruction. Investigating the processes that occur in the early stages of blood‐induced joint disease in humans has been very limited. Therefore, the use of haemophilic animal models is critical to augment the understanding of this phenomenon. This article discusses three cellular regulators (p53, p21 and TRAIL) induced in synovial tissue that are important for iron metabolism. A cartilage remodelling programme induced by the release of cytokines and growth factors that result in articular damage is also discussed. Full elucidation of the pathogenesis of haemophilic joint disease is required to identify new avenues for prevention and therapy.
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