NOVOEIGHT POWDER AND SOLVENT FOR SOLUTION FOR INJECTION 500IU/VIAL

INJECTION, POWDER, FOR SOLUTION

**4.2 Posology and method of administration** Treatment should be initiated under the supervision of a doctor experienced in the treatment of haemophilia. Treatment monitoring During the course of treatment, appropriate determination of factor VIII levels is advised to guide the dose to be administered and the frequency of repeated injections. Individual patients may vary in their response to factor VIII, demonstrating different half-lives and recoveries. Dose based on bodyweight may require adjustment in underweight or overweight patients. In a single dose pharmacokinetic study in adult patients the maximum exposure (Cmax) and the total exposure (AUC) increased with increasing body mass index (BMI) indicating that dose adjustments may be required. An increase in dose may be required for underweight patients (BMI <18.5 kg/m2) and a decrease in dose may be required for obese patients (BMI ≥30 kg/m2), but there is insufficient data to recommend specific dose adjustments, see section 5.2 – _please refer to the Product Insert/Patient Information Leaflet published on HSA for the full drug information_. In the case of major surgical interventions in particular, precise monitoring of the substitution therapy by means of coagulation analysis (plasma factor VIII activity) is indispensable. When using an _in vitro_ thromboplastin time (aPTT)-based one stage clotting assay for determining factor VIII activity in patients’ blood samples, plasma factor VIII activity results can be significantly affected by both the type of aPTT reagent and the reference standard used in the assay. Also there can be significant discrepancies between assay results obtained by aPTT-based one stage clotting assay and the chromogenic assay according to Ph. Eur. This is of importance particularly when changing the laboratory and/or reagents used in the assay. **Posology** The dose and duration of the substitution therapy depend on the severity of the factor VIII deficiency, on the location and extent of the bleeding and the patient’s clinical condition. The number of units of factor VIII administered is expressed in International Units (IU), which are related to the current WHO standard for factor VIII products. The activity of factor VIII in plasma is expressed either as percentage (relative to normal level human plasma) or in International Units (IU) (relative to an International Standard for factor VIII in plasma). One international unit of factor VIII activity is equivalent to that quantity of factor VIII in one ml normal human plasma. _On-demand treatment_ The calculation of the required dose of factor VIII is based on the empirical finding that 1 international unit factor VIII per kg body weight raises the plasma factor VIII activity by 2 international units/dl. The required dose is determined using the following formula: Required units (IU) = body weight (kg) × desired factor VIII rise (%) (IU/dl) × 0.5 (IU/kg per IU/dl). The amount to be administered and the frequency of administration should always be oriented to the clinical effectiveness in the individual case. In case of the following haemorrhagic events, the factor VIII activity should not fall below the given plasma activity level (in % of normal or international units/dl) in the corresponding period. The following table can be used to guide dosing in bleeding episodes and surgery:  _Prophylaxis_ For long term prophylaxis against bleeding in patients with severe haemophilia A, the usual recommended doses are 20–40 international units of factor VIII per kg body weight every second day or 20–50 international units of factor VIII per kg body weight 3 times weekly. In adults and adolesents (>12 years) a less frequent regimen (40–60 international units/kg every third day or twice weekly) may be applicable. In some cases, especially in younger patients, shorter dosage intervals or higher doses may be necessary. _Surgery_ There is limited experience of surgery in paediatric patients. _Elderly_ There is no experience in patients > 65 years. _Paediatric population_ For long term prophylaxis against bleeding in patients below the age of 12, doses of 25–50 international units of factor VIII per kg body weight every second day or 25–60 international units of factor VIII per kg body weight 3 times weekly are recommended. For paediatric patients above the age of 12 the dose recommendations are the same as for adults. **Method of administration** Intravenous use. The recommended infusion rate for NovoEight® is 1–2 ml/min. The rate should be determined by the patient’s comfort level. For instructions on reconstitution of the medicinal product before administration, see Instructions on how to use NovoEight® – _please refer to the Product Insert/Patient Information Leaflet published on HSA for the full drug information_.