Alzheimer drugs don't delay dementia onset: study

Alzheimer drugs don't delay dementia onset: study
LONDON (Reuters) - Giving Alzheimer's drugs to people withearly memory problems does not seem to delay the onset of thedisease, researchers said on Tuesday.
Three main drugs -- Aricept, or donepezil; Exelon, orrivastigmine; and Reminyl, or galantamine -- are currentlyapproved for use in mild-to-moderate Alzheimer's disease.
They are also often prescribed on a so-called "off-label"basis to people with pre-dementia.
But doctors are divided over their effectiveness, leadingto differing rates of use and bitter arguments over patientaccess to treatment, notably in Britain where a dispute overtheir cost-effectiveness has led to legal clashes.
Some experts and patient groups have called for suchanti-cholinesterase drugs to be given to people with mildcognitive impairment (MCI) -- a condition where people havememory problems that are more severe than those normally seenin others of their age.
People with MCI are thought to be at high risk ofdeveloping Alzheimer's or dementia.
Italian researchers, however, found that in none of sixclinical trials they examined did using the drugs significantlyreduce the rate of progression from MCI to dementia.
Accurate assessment of the effect of anti-cholinesterasemedicines was muddied by the lack of a precise definition forMCI, Roberto Raschetti and colleagues at the National Centrefor Epidemiology, Surveillance and Health Promotion in Romereported in the online journal PLoS Medicine.
Their findings may prompt a rethink among doctors who arecurrently using anti-cholinesterase drugs off-label in MCI.Off-label use refers to the common practice of prescribingdrugs for uses for which they are not officially approved.
In Italy, an estimated 27 percent of patients diagnosedwith MCI are given Alzheimer's drugs off-label and Raschettisaid it was likely the situation was similar in othercountries.
He argued more clinical trials were needed, using a singleagreed definition of MCI, before there could be anyjustification for doctors to use the drugs in pre-dementiacases, especially as the drugs can have harmful side effects.
Aricept is marketed by Japan's Eisai Co Ltd and Pfizer Inc,while Novartis AG sells Exelon. Reminyl is sold by Shire Plcand also by Johnson & Johnson under the brand name Razadyne.
A row over who should get these drugs ended up in court inLondon earlier this year after Britain's National Institute forHealth and Clinical Excellence said they should not be given tonewly diagnosed patients with mild Alzheimer's disease.
Drugmakers claimed the agency's cost-effectivenesscalculations were flawed but the court backed the restrictionsin a ruling handed down in August.
(Editing by Sue Thomas)