Building our global family--achieving treatment for all

What is the role for population pharmacokinetics in hemophilia?

Prevention of bleeding in hemophilia requires that plasma levels of the deficient factor exceed the desired minimum target level. Large interindividual variability suggests that knowledge of individual pharmacokinetic (PK) would help to achieve this goal, simultaneously minimizing infusion frequency and the amount of concentrate used. Population PK (PopPK) allows for the incorporation of determinants of interpatient variability and eliminates the need for extensive postinfusion plasma sampling. Barriers to implementation of PopPK are the need for concentrate specific models, Bayesian calculation power, specific expertise for validation and appraisal of forecasted estimates. The Web Accessible Population Pharmacokinetic Service – Hemophilia ( www.wapps-hemo.org ), developed by an international research network of hemophilia centers will test if PK-guided dose individualization can improve patient important outcomes in hemophilia.

Medical co-morbidities and practice

All-oral treatments of hepatitis C (HCV) have been trialled in patients with hereditary bleeding disorders and found to be effective. Further refinements of dosing and duration are being established. Importantly for patient acceptability these regimens are interferon-free. Cohort studies in older patients with haemophilia direct the need for attention to weight control, exercice, assessment of cardiovascular risk, especially hypertension and detection of osteoporosis. Where patients live a long way from a comprehensive care centre, telemedicine connections can engage centre experts with the patient and his/her local practitioners in devising and monitoring care plans.

Radioactive synovectomy with (90) yttrium and (153) samarium hydroxyapatite in haemophilic joints: preliminary study on radiation safety

Most countries still do not achieve 1 IU of factor VIII/capita sufficient for survival. Although primary prophylaxis prevents synovitis, is not universally used. Chronic synovitis is treated with arthroscopy at expense of considerable amount of coagulation factors, and specialized surgeons. Radioactive synovectomy (RS) is a minimally invasive and cost effective alternative to arthroscopy, often considered first the option for persistent synovitis. Even without established causation with cancer, RS is avoided by some, due to this concern. We aim contributing to the understanding of RS safety regarding malignancy, presenting a large number of treated patients, and a single case of cancer. Three centres in Brazil applied RS with (90) Yttrium Citrate, (90) Yttrium hydroxyapatite or (153) Samarium hydroxyapatite in haemophilic joints and performed a survey addressing cancer in these patients. Four hundred and eighty eight patients (ages 3-51) received 1-3 RS (total 842) and follow-up was 6 months to 9 years. One patient aged 14 years presented Ewing sarcoma, 11 months after RS. The tumour was treated successfully with surgery and chemotherapy. Causality of cancer by RS is improbable in this case. Accordingly, latency here is far below minimum 5-10 years for radio-induction of solid tumours. Moreover, ES is not a typically radio-induced tumour, even at high doses. In agreement with others, though recognizing limitations, this study suggests RS is safe regarding cancer induction. Synovitis is a known burden for patients. The decision of making reasonable usage of RS should be outweighed with the risks of leaving synovitis untreated.

New challenges in hemophilia: long-term outcomes and complications

For the past 5 decades, the care for hemophilia patients has improved significantly to the point that a newborn with hemophilia living in a developed nation can expect to have a normal lifespan and a high quality of life. Despite this, there are several new challenges that the hemophilia community will face in the coming years. First, the hemophilia community will soon be challenged with adopting a variety of new agents into clinical practice. Second, the normalization of patients' lives as a result of improved treatment has led to new problem areas, including obese/overweight hemophiliacs and osteoporosis. In addition, although mortality rates are similar to those of the healthy population, morbidities such as hemophilic arthropathy still occur. Third, the cost of care continues to rise, both due to the development of expensive new therapies and to the costs of managing problems such as obesity and osteoporosis. Finally, most patients in the world with hemophilia receive little to no care and although this is an enormous challenge, it must be confronted. This review discusses some new challenges facing developing nations and their care for hemophilia patients. In summary, in hemophilia in the coming few years, several new challenges will need to be confronted.

An investigation of the spectrum of common and rare inherited coagulation disorders in north-eastern Iran

BACKGROUND

Health care officials and legislators need accurate data on prevalence and numbers of individuals with bleeding disorders in order to plan and allot their budgets; the manufacturers of coagulation factors also need these data to estimate the amount of factors required to prevent scarcity of these products.

MATERIALS AND METHODS

We surveyed the prevalence of haemophilia A, haemophilia B, von Willebrand's disease and rare bleeding disorders in North-Eastern Iran. The survey was done in the period from September 2009 to March 2011. Information was collected from the medical records in three major hospitals and a haemophilia centre; the patients' updated data were obtained by telephone.

RESULTS

Overall in the current survey 552 patients with inherited coagulation disorders were identified and their medical records obtained. Of these, 429 (77.5%) had common bleeding disorders (haemophilia A, haemophilia B, von Willebrand's disease), 85 (15.6%) had rare bleeding disorders (deficiency of coagulation factors V, VII, X, XIII, I, XI, combined factor V and VIII deficiency) and 38 (6.9%) had platelet disorders.The commonest bleeding disorders were haemophilia A (n=287, 51.9%), haemophilia B (n=92, 16.6%), von Willebrand's disease (n=50, 9%), factor V deficiency (n=21, 3.8%), factor VII deficiency (n=19, 3.4%), factor X deficiency (n=2, 0.36%), combined factor V and VIII deficiency (n=28, 5.8%), factor XIII deficiency (n=11, 1.99%), factor XI deficiency (n=2, 0.4%), afibrinogenaemia (n=2, 0.36%) and platelet disorders (n=38, 6.9%).

DISCUSSION

There is notable population of individuals with bleeding disorders in North-Eastern Iran.

Haemophilia: provision of factors and novel therapies: World Federation of Hemophilia goals and achievements

For nearly 50 years, the goal of the World Federation of Hemophilia (WFH) has been to achieve 'Treatment for All' patients with inherited bleeding disorders, regardless of where they live. With proper diagnosis, management and care, people with bleeding disorders can live perfectly healthy lives. Without treatment, the reality is that many will die young or, if they survive, suffer joint damage that leaves them with permanent disabilities. Only about 25% of the estimated 400 000 people with haemophilia worldwide receive adequate treatment. The percentage is far lower for those with von Willebrand Disease (VWD) and the rarer bleeding disorders. The achievements of the WFH to close the gap in care for people with bleeding disorders are measureable over time by using three key indicators; the difference in the estimated and actual number of people known with bleeding disorders, the amount of treatment products needed versus that available, and the number of people born with bleeding disorders and the number who reach adulthood. There are five essential elements to achieve a sustainable national care programme: ensuring accurate laboratory diagnosis, achieving government support, improving the care delivery system, increasing the availability of treatment products, and building a strong national patient organization.