Galantamine hydrobromide (Reminyl) tablets are now available for the treatment
of mild to moderately severe Alzheimer’s disease (see p501).
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| Galantamine was derived from daffodils |
The drug is an alkaloid derived from daffodils, although it is now produced
synthetically. It was launched on September 21.
Shire Pharmaceuticals, the UK manufacturer of the drug, says that galantamine
has two modes of action — inhibition of acetylcholinesterase and “modulation”
of nicotinic receptors in the brain.
Reduced levels of acetylcholine are thought to result in the symptoms of Alzheimer’s
disease, so preserving acetylcholine levels by reducing its breakdown (acetylcholinesterase
inhibition) and possibly increasing its release (nicotinic receptor modulation)
could slow down the patient’s decline. However, it is not yet known what
impact modulation of nicotinic receptors has clinically.
Over 3,200 patients worldwide have taken part in six clinical trials. These
showed that galantamine was the only treatment for Alzheimer’s disease
that had a positive effect on cognitive impairment, activities of daily living,
behavioural disturbances and the impact of these three factors on the carer,
Shire says.
The dose is, initially, 4mg twice a day, which should be increased after four
weeks to a maintenance dose of 8mg twice a day. The summary of product characteristics
says that patients should be reassessed on a regular basis and the drug discontinued
when it no longer provides any clinical benefit.