(Please refer to the Summary of Product Characteristics before prescribing)
IDELVION (albutrepenonacog alfa; recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP)) 250 IU, 500 IU, 1000 IU and 2000 IU powder and solvent for solution for injection. Idelvion 250 IU, 500 IU and 1000 IU vials reconstituted with 2.5ml of water for injections contain approximately 100 IU/ml, 200 IU/ml and 400 IU/ml of albutrepenonacog alfa respectively. Idelvion 2000 IU vial reconstituted with 5 ml water for injections approximately contains 400 IU/ml of albutrepenonacog alfa.
Indications: Treatment and prophylaxis of bleeding in patients with haemophilia B (congenital factor IX deficiency). Idelvion can be used for all age groups.
Posology and method of administration: On demand treatment: The calculation of the required dose is based on the empirical finding that 1 International Unit (IU) factor IX per kg body weight is expected to increase the circulating level of factor IX by an average of 1.3 IU/dl (1.3 % of normal) in patients ≥ 12 years of age and by 1.0 IU/dl (1.0 % of normal) in patients < 12 years of age. The required dose is determined using the following formulae, refer to SPC for dosing calculation examples:
Patients <12 years of age:
For an incremental recovery of 1 IU/dl per 1 IU/kg, the dose is calculated as follows:
Dose (IU) = body weight (kg) x desired factor IX increase (IU/dl) x 1 dl/kg
Patients ≥12 years of age:
For an incremental recovery of 1.3 IU/dl per 1 IU/kg, the dose is calculated as follows:
Dose (IU) = body weight (kg) x desired factor IX increase (IU/dl) x 0.77 dl/kg
For dosing in haemorrhagic events and surgery see SPC. Prophylaxis (adult and paediatric patients): the usual doses are 35 to 50 IU/kg once weekly. Well-controlled patients on a once-weekly regimen may be treated with up to 75 IU/kg on an interval of 10 or 14 days (see SPC for further information). In some cases e.g. younger patients, shorter dosage intervals or higher doses may be necessary. After a bleeding episode during prophylaxis, patients should maintain their prophylaxis regimen as closely as possible, with two doses of Idelvion being administered at least 24 hours apart but longer as deemed suitable. For instructions on reconstitution see SPC. The reconstituted preparation should be injected slowly intravenously at a rate comfortable for the patient up to a maximum of 5 ml/min. The safety and efficacy of Idelvion in previously untreated patients have not yet been established.
Contraindications: Hypersensitivity to the active substance or to any of the excipients (see SPC for a list). Known allergic reaction to hamster protein (Idelvion contains traces of hamster proteins).
Special warnings and special precautions for use: The listed warnings and precautions apply to both adults and paediatrics. Idelvion contains up to 25.8 mg (1.13 mmol) sodium per dose (bodyweight 70 kg). Allergic type hypersensitivity reactions are possible. If symptoms of hypersensitivity occur, patients should be advised to discontinue use of the medicinal product immediately and contact their physician. Patients should be informed of the early signs of hypersensitivity reactions including hives, generalised urticaria, and tightness of the chest, wheezing, hypotension and anaphylaxis. In case of shock, the current medical standards for shock treatment should be observed. It is suggested that the initial administrations should be performed under medical observation. Monitor for neutralising antibodies (inhibitors) after repeated treatment. Reports in literature show a correlation between factor IX inhibitor occurrence and allergic reactions. Patients experiencing allergic reactions should be evaluated for the presence of an inhibitor. Patients with factor IX inhibitors may be at an increased risk of anaphylaxis with subsequent challenge with factor IX.
Due to a potential risk of thrombotic complications, patients with liver disease, post-operatively, newborn infants, patients at risk of thrombotic phenomena or DIC should be monitored for early signs of thrombotic and consumptive coagulopathy. The benefit of treatment should outweigh the risk of these complications. In patients with existing cardiovascular risk factors, substitution therapy with FIX may increase the cardiovascular risk. If a central venous access device (CVAD) is required, risk of CVAD-related complications should be considered. Name and batch number of the product administered should be recorded.
Pregnancy and Lactation: Administer only if clearly indicated and benefit outweighs risk.
Undesirable effects: Frequency, type and severity of adverse reactions in children are expected to be similar as in adults. During treatment with Idelvion the following adverse reactions may occur: Injection site reactions, headache, hypersensitivity or allergic reaction, dizziness, rash and eczema. In some cases hypersensitivity may progress to severe anaphylaxis (including shock) and may occur in close temporal association with development of factor IX inhibitors.
Patients with haemophilia B may develop neutralising antibodies to factor IX; the condition will manifest itself as an insufficient clinical response. Nephrotic syndrome has been reported following attempted immune tolerance induction in haemophilia B patients with factor IX inhibitors and a history of allergic reaction. Factor IX products obtained from CHO cells very rarely cause development of antibodies to hamster protein. There is a potential risk of thromboembolic episodes following administration of factor IX products, with a higher risk for low purity preparations, there have been instances of: myocardial infarction, disseminated intravascular coagulation, venous thrombosis and pulmonary embolism. The use of high purity factor IX is rarely associated with such adverse reactions. Please refer to the SPC for further information
NHS List Price: 250 IU: £522.50; 500 IU: £1045.00; 1000 IU: £2090.00; 2000 IU: £4180.00.
Legal Category: POM, Marketing Authorisation number: Idelvion 250: EU/1/16/1095/001, Idelvion 500: EU/1/16/1095/002, Idelvion 1000: EU/1/16/1095/003, Idelvion 2000: EU/1/16/1095/004
Further information available from: CSL Behring UK Ltd, Haywards Heath, West Sussex, RH16 1AH.
Date text last revised: 27 July 2017
Adverse events should also be reported to CSL Behring UK Ltd. on 01444 447 405