The DOMINO trial has demonstrated that continued treatment with donepezil is beneficial for patients with moderate to severe Alzheimer’s disease. In these patients, donepezil slows the decline of cognitive function and activities of daily living. The trial also showed that there were no important benefits of combination therapy with memantine and donepezil compared to donepezil alone.
Alzheimer’s disease is the commonest cause of dementia. There are 750,000 living with dementia today in the UK and this number is expected to rise to over 1 million by 2021. There is no cure for Alzheimer’s disease although there are drugs that have been shown to be effective for disease in the mild to moderate range of severity. However, there is inadequate evidence to guide treatment decisions for patients who have reached the moderate to severe point.
DOMINO was a blinded 2x2 factorial randomised controlled trial where patients were randomly allocated to either continue donepezil only, continue donepezil and start memantine, discontinue donepezil and start memantine or discontinue donepezil and do not start memantine. The trial was conducted to evaluate whether treatment with donepezil or memantine or both combined were effective at slowing the decline of cognitive function and activities of daily living. A total of 295 patients were randomised into the trial and were followed up for a total of 12 months. The results of the trial have now been published in the New England Journal of Medicine.
The trial report was accompanied in the journal by an editorial noting the importance of the results in patients that are severely impaired, a group that is not often studied in clinical trials.
Further information about the trial can be found in the published protocol. The study was sponsored by King’s College London and funded by the MRC and the Alzheimer’s Society. The MRC CTU was responsible for statistical analysis and oversight and some aspects of data management.