The dementia drug donepezil (Aricept), already widely used to treat mild to moderate Alzheimer's disease, can also help in moderate to severe patients, according to a report funded by the UK Medical Research Council (MRC) and the Alzheimer's Society. The study suggests that extending treatment to this group could help treat twice as many sufferers worldwide. Encouragingly, the drug has greater positive benefits for patients more severely affected than for those in the earlier stages of dementia.
It is estimated that 18 million people worldwide suffer from Alzheimer's disease, which is the most common cause of dementia. According to the World Health Organization, of the 35 million people currently living with dementia globally, 58% live in low- and middle-income countries and by 2050 this figure is projected to reach 71% of the total.
The multi-centre UK study, led by Professor Robert Howard at King's College London, is the first trial to demonstrate the value of continued drug intervention for those patients with moderate to severe Alzheimer's disease who have deteriorated beyond the point where donepezil is currently recommended.
The study, to be published in the New England Journal of Medicine, looked at two drugs: donepezil and memantine. Donepezil is the most commonly prescribed of the dementia drugs and is recommended for patients at the earliest stages of Alzheimer's disease. Doctors are currently advised to stop prescribing donepezil when the disease progresses to become moderate to severe and until now there has been no clear evidence that continuing treatment is of benefit to patients.
Over the course of the trial, patients who continued to take donepezil showed considerably less decline in cognition - memory, orientation, language function - and function (retained ability to carry out simple daily tasks and self-care) than those taking a placebo drug. The benefits seen with continued treatment were clinically important and were greater than those previously seen in patients with less severe Alzheimer's disease. Whilst the effect was slightly smaller, starting memantine treatment also resulted in significantly better cognitive and functional abilities compared with those taking a placebo.
Professor Robert Howard, lead author from the Institute of Psychiatry at King's says: "As patients progress to more severe forms of Alzheimer's disease, clinicians are faced with a difficult decision as to whether to continue or not with dementia drugs and, until now, there has been little evidence to guide that decision. For the first time, we have robust and compelling evidence that treatment with these drugs can continue to help patients at the later, more severe stages of the disease. We observed that patients who continued taking donepezil were better able to remember, understand, communicate and perform daily tasks for at least a year longer than those who stopped taking the drugs. These improvements were noticeable to patients, their caregivers and doctors. Both donepezil and memantine will soon be off patent and available in very cheap generic preparations. These findings will greatly increase the numbers of patients in the developed and developing world that we are able to treat."
Professor Nick Fox, MRC Senior Clinical Fellow at the Institute of Neurology, University College London, says: "The number of people with Alzheimer's disease and other forms of dementia is reaching critical levels. It has never been more important to invest in research which will enable doctors to make informed decisions based on the best evidence possible when deciding what treatments to give patients. The MRC has an ongoing commitment to the development of effective, safe treatments that will improve the quality of life for people with Alzheimer's disease and their care givers."
Professor Clive Ballard, Director of Research at Alzheimer's Society, says: "Thanks to the Alzheimer's drug donepezil, tens of thousands of people in the early to moderate stages of the condition are able to recognise their family for longer, play with their grandchildren and make vital plans for the future. This major new trial now shows that there could also be significant benefits on continuing the treatment into the later stages too. There are 750,000 people with dementia in the UK yet currently prescription levels of Alzheimer's drugs are still low. If this is to change we have to improve the shocking diagnosis rates and ensure everyone is given the opportunity to try treatments."
The study was sponsored by King's College London and funded by the UK Medical Research Council (MRC) and Alzheimer's Society. Pfizer-Eisa and Lundbeck donated supplies of drugs but had no involvement in the study design, conduct analyses or reporting.
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Notes to editors
1. Howard et al 'Donepezil and Memantine for Moderate-to-Severe Alzheimer's Disease' is published in New England Journal of Medicine.
2. Researchers followed 295 patients living in London and 14 other UK centres to investigate different drug regimens on patients who had been previously treated with donepezil. The trial was split into four different arms:
(i) continue donepezil;
(ii) stop donepezil and receive a placebo;
(iii) stop donepezil and receive memantine;
(iv) take both donepezil and memantine in combination.
WHO information on dementia epidemic in Asia: http://www.who.int/bulletin/volumes/89/3/11-020311/en/
About King's College London
King's College London is one of the top 30 universities in the world (2011/12 QS international world rankings), and was The Sunday Times 'University of the Year 2010/11', and the fourth oldest in England. A research-led university based in the heart of London, King's has nearly 23,500 students (of whom more than 9,000 are graduate students) from nearly 140 countries, and some 6,000 employees. King's is in the second phase of a £1 billion redevelopment programme which is transforming its estate.
King's has an outstanding reputation for providing world-class teaching and cutting-edge research. In the 2008 Research Assessment Exercise for British universities, 23 departments were ranked in the top quartile of British universities; over half of our academic staff work in departments that are in the top 10 per cent in the UK in their field and can thus be classed as world leading. The College is in the top seven UK universities for research earnings and has an overall annual income of nearly £525 million (year ending 31 July 2011).
King's has a particularly distinguished reputation in the humanities, law, the sciences (including a wide range of health areas such as psychiatry, medicine, nursing and dentistry) and social sciences including international affairs. It has played a major role in many of the advances that have shaped modern life, such as the discovery of the structure of DNA and research that led to the development of radio, television, mobile phones and radar. It is the largest centre for the education of healthcare professionals in Europe; no university has more Medical Research Council Centres.
King's College London and Guy's and St Thomas', King's College Hospital and South London and Maudsley NHS Foundation Trusts are part of King's Health Partners. King's Health Partners Academic Health Sciences Centre (AHSC) is a pioneering global collaboration between one of the world's leading research-led universities and three of London's most successful NHS Foundation Trusts, including leading teaching hospitals and comprehensive mental health services. For more information, visit: www.kingshealthpartners.org.
The College is in the midst of a five-year, £500 million fundraising campaign - World questions|King's answers - created to address some of the most pressing challenges facing humanity as quickly as feasible. The campaign's three priority areas are neuroscience and mental health, leadership and society, and cancer. More information about the campaign is available at www.kcl.ac.uk/kingsanswers.
For almost 100 years the Medical Research Council has improved the health of people in the UK and around the world by supporting the highest quality science. The MRC invests in world-class scientists. It has produced 29 Nobel Prize winners and sustains a flourishing environment for internationally recognised research. The MRC focuses on making an impact and provides the financial muscle and scientific expertise behind medical breakthroughs, including one of the first antibiotics penicillin, the structure of DNA and the lethal link between smoking and cancer. Today MRC funded scientists tackle research into the major health challenges of the 21st century. www.mrc.ac.uk
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