In vitroandin vivostability of diluted recombinant factor VIII for continuous infusion use in haemophilia A

International Society on Thrombosis and Haemostasis Clinical Practice Guideline for Treatment of Congenital Haemophilia-A Critical Appraisal

INTRODUCTION

Evidence-based clinical practice guidelines drive optimal patient care and facilitate access to high-quality treatment. Creating guidelines for rare diseases such as haemophilia, where evidence does not often come from randomized controlled trials but from non-randomized and well-designed observational studies and real-world data, is challenging. The methodology used for assessing available evidence should consider this critical fact. In formulating guidelines, it is essential to include treatment goals and patient preference.

AIM

This paper comprehensively critiques, against this background, the recommendations of the ISTH clinical practice guidelines for the treatment of haemophilia.

METHODS

Each recommendation was critically reviewed against available evidence as well as existing guidelines and commented upon for its scientific validity, impact on clinical practice and access to care globally. The validity of the way in which the GRADE methodology was applied to existing evidence was also assessed.

RESULTS

The critique provided shows that these recommendations have major limitations: they did not state treatment goals and contradict existing guidelines; opportunities for providing access to innovation were missed when the therapeutic benefits of the products approved in the last decades were not included. A major reason for this is the inappropriate adoption of the GRADE methodology without adaptations and without considering treatment goals and patient-relevant outcomes.

CONCLUSION

These recommendations may mislead healthcare professionals, payers and governments and therefore cannot serve the patient community well. They setback the advances made in haemophilia care because they overlook important available evidence and do not guide clinical practice to contemporary standards.

Stability of Turoctocog Alfa, a Recombinant Factor VIII Product, during Continuous Infusion In Vitro

Objective  Turoctocog alfa is a recombinant factor VIII (rFVIII) for the prevention and treatment of bleeding in patients with hemophilia A, including those undergoing surgery and invasive medical procedures. This in vitro study evaluated the physical and chemical stability of turoctocog alfa during continuous infusion (CI) over 24 hours at 30°C.

Materials and Methods  The study was performed at 30°C ( ± 2°C). A CI system with pump speed set at either 0.6 or 1.5 mL/h was used to evaluate the stability of three turoctocog alfa strengths (500, 1,000, and 3,000 IU), equating to doses of 1.1 to 16.1 IU/h per kilogram of body weight. The following parameters were evaluated at selected time points between 0 and 24 hours: appearance of solution, clarity, pH, potency, purity, content, total high molecular weight proteins (HMWPs), and oxidized rFVIII.

Results  The mean potency of turoctocog alfa was maintained within the predefined acceptance criteria during CI for both pump speeds with all three strengths at 6, 12, or 24 hours (500 IU: ≥484 IU/vial; 1,000 IU: ≥1,014 IU/vial; and 3,000 IU: ≥3,029 IU/vial). Furthermore, the appearance of solution, clarity, pH, purity, content of turoctocog alfa, total HMWP, and oxidized forms were also within the predefined limits, and comparable to the reference samples (time = 0 hours) for the pump speeds and product strengths assessed.

Conclusion  Physical and chemical stability of turoctocog alfa was maintained during CI over 24 hours. There was only minor degradation or changes in any of the parameters tested. Potency was within the prespecified acceptance limits throughout 24 hours of infusion. These findings confirm the suitability of turoctocog alfa for CI.

Continuous infusion of coagulation factor concentrates during intensive treatment

In clinical management of bleeds and surgical procedures in patients suffering from bleeding disorders either repetitive bolus injections (BI) or continuous infusion (CI) can be used for coagulation factor replacement. Continuous infusion seems to be an attractive route of administration and may be considered if replacement therapy is required for more than 3 days. The strongest argument favouring continuous infusion is its superiority in providing the patient with a safe and constant level of the deficient coagulation factor by balancing input with clearance. Furthermore, several studies have shown that coagulation factor consumption may be reduced by CI compared to repetitive bolus injections (BI) since unnecessary peaks of factor level are avoided. Concerns have been raised whether continuous infusion of coagulation concentrates is associated with an increased risk of developing inhibitors. However, available data have so far not shown an increased risk for inhibitor development in severe haemophilia patients with more than 50 exposure days of coagulation factor concentrates. Further, previously reported complications when using CI such as phlebitis at the infusion site and pump failure are nowadays very seldom seen when small amounts of heparin are added to the infusion bag, and increased quality of the pumps are available. Over the last decades, numerous reports have confirmed CI to be a safe and effective mode of coagulation factor replacement even in the most challenging surgical procedures, such as total joint arthroplasties.

Extended Stability and Sterility of Antihemophilic Factor Human

OBJECTIVES

Antihemophilic factor human is a factor VIII product used to supplement those with hemophilia. Recent data show treatment benefit and cost saving opportunities if factor products are administered as a continuous infusion rather than conventional bolus dose. This method has not been widely used given the lack of evidence for safe and effective use beyond 3 hours from preparation. The objectives of this study were to determine the physical and chemical stability and sterility of antihemophilic factor human over a 7-day period.

METHODS

Antihemophilic factor human was obtained from the manufacturer. Baseline stability and sterility were determined by factor activity levels along with bacterial and fungal cultures. These tests were also evaluated over a span of 7 days at room temperature and under refrigeration.

RESULTS

Each sample was inspected at the time of delivery and showed no visible signs of physical changes. Factor activity levels were maintained between 88% and 102% of baseline measurements. No growth was observed for bacterial or fungal cultures in any sample after 4 weeks of incubation.

CONCLUSIONS

Antihemophilic factor human maintained physical stability and chemical stability and remained sterile for the 7-day period, allowing extended stability and continuous infusions to be considered.

A longitudinal prospective study of bleeding diathesis in Egyptian pediatric patients: single-center experience

Keeping an updated registry of bleeding disorders is crucial for planning care and documenting prevalence. We aimed to assess the prevalence of various bleeding disorders including rare inherited coagulation and platelet disorders concerning their clinico-epidemiological, diagnostic data and bleeding manifestations severity. Patients suffering from manifestations of bleeding or coagulation disorders presented to Hematology Clinic during 16 years were included and prospectively followed up. Demographics, clinical characteristics, complete blood count, bleeding, prothrombin and activated partial thromboplastin times, platelet aggregation tests and bone marrow aspiration were recorded. Overall 687 patients with bleeding disorders from total 2949 patients were identified. Inherited coagulation defects were found in 27.2%; hemophilia A (70.6%), hemophilia B (13.9%), factor I deficiency (2.3%), factor V deficiency (1.6%), factor X deficiency (4.2%), factor VII deficiency (2.6%), factor XIII deficiency (1.1%), combined factor deficiency (2.1%) and unclassified coagulation disorders in 1.6% of studied patients. Overall 72.7% had diagnosed with platelet disorders; immune thrombocytopenia was the commonest (74.8%), and inherited conditions represent (25.2%) in the following order: Glanzman's thrombasthenia (11.2%), von Willebrand disease (6.6%), Bernard-Soulier syndrome (1%) and Chediak Higashi in 0.4% and unclassified in 6%. Median age of diagnosis of coagulation and platelet disorders were 33 and 72 months. Presenting symptoms of coagulation disorders were: 25.1% post circumcision bleeding, 22.5% ecchymosis, 20.9% hemoarthrosis and 15% epistaxis. Symptoms of rare coagulation disorders were postcircumcision bleeding (20%), bleeding umbilical stump (20%), epistaxis (12%), hemoarthrosis (8%) and hematomas (4%). Presenting symptoms in rare inherited platelet disorders were purpura, ecchymosis, epistaxis and bleeding gums, respectively. Analysis of the clinico-epidemiological data of patients with bleeding disorders is a useful tool for monitoring and improving their quality of care.