Alzheimer's: have researchers really found the answer?
Publication Date:31/07/2008
It can be heartbreaking to have a friend or relative with Alzheimer's disease. When someone you love struggles to remember your name, it's natural to be hopeful about anything that might help. Several drugs have been highlighted in recent news reports as potential new treatments for Alzheimer's. Here, we take a closer look.
What is Alzheimer's disease?
Alzheimer's disease affects 1 in 5 people over the age of 80. It causes confusion and memory loss, and people with Alzheimer's often end up needing full-time care. Drugs can be used to reduce the symptoms, but they only have a small impact. There's no cure for Alzheimer's.
Why are all these new treatments in the news?
Over the past few days, researchers have been gathered in Chicago for the International Conference on Alzheimer's Disease. Scientists often use these conferences to present results from their research.
Some of the research has looked at completely new, experimental drugs. Other scientists have been looking at drugs that are already used for other conditions, to see whether they could also work for Alzheimer's.
What are the potential new drugs?
Two Alzheimer's drugs are in early-stage trials. The first is called methylthioninium chloride (its brand name is Rember). The second is still known by its researchers' code name, PBT2.
Both drugs show some promise, but they're still in phase II trials. These trials look at how well a drug works for a medium-sized group of patients, normally a couple of hundred. The study on PBT2 looked at 78 people, and the research on Rember looked at 341.
If a drug is successful in phase II trials, and doesn't cause major side effects, it can be tested in large numbers of people, probably several thousand. If the drug is proved to work in large trials, its manufacturer can apply to the UK or European drug regulator for a licence to manufacture and sell the drug. Once a new drug is licensed, there's also the question of whether NICE approves it for use on the NHS.
As you can see, a lot of things need to happen between phase II trials and a drug being available to treat patients. It can take years, and there's no guarantee that the drug will ever be available. So, while Rember and PBT2 offer hope for the future, they're unlikely to be available outside clinical trials for some time yet.
What about drugs used for other medical conditions?
Researchers have also been looking at existing drugs, to see if they can help people with Alzheimer's. For example, drugs called statins help people with unhealthy levels of cholesterol. And angiotensin receptor blockers (ARBs) help bring down high blood pressure. Researchers hope these drugs might also help prevent or treat Alzheimer's.
Two new studies have looked at people taking stains or ARBs to treat their high cholesterol or blood pressure. These people also seemed to get some protection against Alzheimer's. However, although there's promise, we need more research to find out whether these drugs really do prevent Alzheimer's, and to make sure the benefits outweigh the side effects in the long term.
For the time being, doctors are unlikely to prescribe either statins or ARBs to prevent Alzheimer's.
What treatments are used for Alzheimer's now?
There are three drugs approved in the UK to treat moderate Alzheimer's disease. They're called donepezil, galantamine and rivastigmine. They aim to improve people's memories, and make them less confused. Research shows they can help with these symptoms, although only by a small amount.
Drugs known as antipsychotics have sometimes been used to treat Alzheimer's, to help people who are agitated or are having delusions. These drugs include risperidone and olanzapine. However, these two drugs aren't generally recommended now, as they can increase the risk of a stroke in elderly people.
Are there any alternative treatments?
There's limited research to show that a herbal remedy called ginkgo biloba may help a little with symptoms like forgetfulness and confusion, and it doesn't seem to have side effects. If you're interested in this herbal treatment, be sure to discuss it with your doctor first. Gingko biloba can sometimes be harmful when taken with conventional medicines, especially those used to prevent blood clots.
Always buy herbal treatments from a reputable source, because different products can vary in quality. The studies we looked at used extracts of ginkgo biloba that were very pure.
What about the future?
If you're looking after someone with Alzheimer's, especially if you're on your own, it can be very difficult to cope. There will probably be a time when you need to get help at home, or think about full-time care in a nursing home. Make sure you get all the help you can, for example from your family, the NHS and social services. There are also local carers' groups that may be able to give you advice and support.
From:
You can read more about the latest research at the conference website (http://www.alz.org/icad). The research on PBT2 appeared in a medical journal called The Lancet Neurology (Lannfelt L , Blennow K, Zetterberg H, et al. Safety, efficacy, and biomarker findings of PBT2 in targeting Abeta as a modifying therapy for Alzheimer’s disease: a phase IIa, double-blind, randomised, placebo-controlled trial. Published online July 29, 2008).
To find out more, see our information on Alzheimer's and other forms of dementia.
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This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
