The National Institute for Health and Clinical Excellence is asking Boehringer Ingelheim for more information on its product Pradaxa (dabigatran), used in the prevention of stroke and systemic embolism in people with atrial fibrillation.

Pradaxa is an orally-administered anticoagulant that inhibits the formation of the thrombin enzyme. It has a UK marketing authorisation for the prevention of stroke and systemic embolism in patients aged 75 years and over with nonvalvular atrial fibrillation who have had a previous stroke, transient ischaemic attack or system embolism, and/or left ventricular ejection fraction below 40%, and/or symptomatic heart failure of New York Heart Association Class 2 or above.

The product also has a UK marketing authorisation for people with AF aged 65 years or over who have diabetes, coronary heart disease or hypertension.

Commenting on NICE's request for further information contained within this preliminary recommendation, the Institute's deputy chief executive, Dr Gillian Leng, said that NICE's independent Appraisal Committee had heard that warfarin, the most commonly-used antithrombotic, is associated with a number of inconveniences for the patient, including regular monitoring and dose adjustments which cause disruption and changes to routine, that make compliance difficult.

Since Pradaxa does not require frequent blood tests to determine the effectiveness of treatment, it may have potential benefits for people with AF, she said. The Committee had also accepted evidence showing that Pradaxa 150mg twice daily was more clinically effective than warfarin in reducing the risk of stroke/systemic embolism, ischaemic stroke and vascular mortality, and that this represented an important development for patients with AF, added Dr Leng, who is also chief operating officer for NHS Evidence.

Clarify cost effectiveness, BI told

However, she continued that the Committee has requested additional information from Boehringer Ingelheim in a number of areas. "In particular, it is seeking clarification of the cost-effectiveness of the licensed regimen, in which people aged under 80 years begin treatment with dabigatran 150mg twice daily, and at age 80 years switch to dabigatran 110mg twice daily," she said.

"It has requested cost-effectiveness analysis of this sequential regimen compared with warfarin using more robust data to estimate effectiveness, and a more plausible set of assumptions about the drug's use in clinical practice. These include lowering costs for anticoagulation monitoring that than suggested in the manufacturer's submission and modelling a patient population more representative of the AF patient population in the UK than was used in the manufacturer's original analysis," said Dr Leng.

NICE emphasises that it has not yet issued final guidance - which is likely to be published in December - and that the decisions contained within this preliminary recommendation may change after consultation.