Dabigatran etexilate for the prevention of stroke and systemic embolism in atrial fibrillation

Dabigatran etexilate (Pradaxa, Boehringer Ingelheim; hereafter referred to as dabigatran) is an orally administered anticoagulant that inhibits the thrombin enzyme. Dabigatran has a UK marketing authorisation for the 'prevention of stroke and systemic embolism in adult patients with non-valvular atrial fibrillation with 1 or more of the following risk factors:

• previous stroke, transient ischaemic attack, or systemic embolism

• left ventricular ejection fraction below 40%

• symptomatic heart failure of New York Heart Association (NYHA) class 2 or above

• age 75 years or over

• age 65 years or over with 1 of the following: diabetes mellitus, coronary artery disease, or hypertension'.

The summary of product characteristics states that the recommended daily dose of dabigatran is 300 mg taken as one 150-mg capsule twice daily. Therapy is continued long term. For patients aged 75 to 80 years, a dose of 220 mg taken as one 110-mg capsule twice daily can be considered at the discretion of the physician for individual patients whose thromboembolic risk is low and bleeding risk is high. Patients aged 80 years or older should be treated with a daily dose of 220 mg taken as one 110-mg capsule twice daily because of the increased risk of bleeding in this population.

Dabigatran is contraindicated in people with severe renal impairment, active clinically significant bleeding, organic lesions at risk of bleeding, impairment of haemostasis, and hepatic impairment or liver disease expected to have an impact on survival. Concomitant treatment with systemic ketoconazole, cyclosporine, itraconazole or tacrolimus is also contraindicated. The most common adverse events in people receiving dabigatran are anaemia, abdominal pain, diarrhoea, dyspepsia, gastrointestinal haemorrhage, genitourinary haemorrhage (patients may notice blood in their urine), nausea and nose bleeds. For full details of adverse reactions and contraindications, see the summary of product characteristics.

Dabigatran is available as 110 mg and 150 mg capsules and comes in packs of 60 capsules. The manufacturer has stated that the cost to the NHS of a pack of 60 capsules of either dabigatran 110 mg or 150 mg will be £75.60 (excluding VAT). The cost per day per patient based on the recommended dosage will be £2.52 (excluding VAT). Costs may vary in different settings because of negotiated procurement discounts.