Drugs Xagena
MHRA ( Medicines and Healthcare Products Regulatory Agency ) previously advised that the contraindications for Dabigatran ( Pradaxa ) had been clarified to include a range of clinical conditions where the patient is at significant risk of major bleeding, as well as in combination with other anticoagulant agents. Because similar risks are associated with the other new oral anticoagulants ( Apixaban [ Eliquis ] and Rivaroxaban [ Xarelto ] ), these contraindications have been applied across all three new oral anticoagulants for all indications and doses.
Dabigatran is a potent, orally active, direct inhibitor of free thrombin, fibrin-bound thrombin and thrombin-induced platelet aggregation.
Apixaban and Rivaroxaban are direct, highly selective, orally active inhibitors of activated factor X ( factor Xa ).
All three new oral anticoagulants are licensed for: prevention of venous thromboembolic events in adults who have had elective total hip-replacement or knee-replacement surgery; prevention of stroke and systemic embolism in adults with non-valvular atrial fibrillation and one or more cardiovascular risk factors.
Rivaroxaban is additionally licensed for: treatment of deep-vein thrombosis and pulmonary embolism, and prevention of their recurrence, in adults.
Risk of haemorrhage
Haemorrhage is a common adverse effect of all anticoagulants. Although these three new oral anticoagulants have some differing contraindications due to their different properties, the contraindications in patients with conditions putting them at significant risk of major bleeding, and those relating to use with other concomitant anticoagulants, now apply to all three of the medicines. This is the result of a European review.
Updated advice on contraindications and warnings
The following contraindications now apply to all three new oral anticoagulants, for all doses and indications:
A lesion or condition, if considered a significant risk factor for major bleeding. This may include: current or recent gastrointestinal ulceration; presence of malignant neoplasm at high risk of bleeding; recent brain or spinal injury; recent brain, spinal, or ophthalmic surgery; recent intracranial haemorrhage; known or suspected oesophageal varices; arteriovenous malformation; vascular aneurysms, or major intraspinal or intracerebral vascular abnormalities.
Concomitant treatment with any other anticoagulant agent, eg, unfractionated Heparin, low molecular weight Heparin ( such as Enoxaparin or Dalteparin ), Heparin derivatives ( such as Fondaparinux ), or oral anticoagulants ( such as Warfarin ). Exceptions are switching of therapy to or from the medicine, or when unfractionated Heparin is given at doses necessary to maintain an open central venous or arterial catheter.
Additional advice and information for healthcare professionals
Special care should be taken when deciding to prescribe these anticoagulant medicines to patients with other conditions, procedures, and concomitant treatments ( eg, non-steroidal anti-inflammatory drugs, antiplatelets ), which may increase the risk of major bleeding.
Attention should be paid to renal function. Impaired renal function may constitute a contraindication or recommendation not to use the anticoagulant medicine, or may require a dose reduction; recommendations differ for the three medicines.
The contraindications, posology, and warnings and precautions for use specific to each medicine, together with the individual’s risk factors for bleeding ( eg, renal function ), should be considered before prescribing these medicines.
There is no specific antidote available for any of these three new oral anticoagulants. ( Xagena )
Source: Drug Safety Update 2013; volume 7 issue 3: A1
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