Medications containing the drug memantine are supposed to help people who have Alzheimer’s disease remember things and better manage their daily tasks. Trials show that memantine can somewhat delay the deterioration of mental abilities. Other abilities important to daily life may also last longer.
Dementia is a chronic and progressive disease affecting the brain, in which the nerve cells change or become damaged. The most common form of dementia is Alzheimer’s disease. This disease causes the person’s mental abilities – especially memory – and emotional control to deteriorate. It becomes increasingly difficult to master everyday activities which used to be easy, such as going shopping, doing household chores, and even eating and drinking. Accompanying symptoms, including depression, anxiety and sleeping problems, can seriously reduce quality of life too. As the disease progresses, carers have to support and look after their loved ones more and more, and they have to find a way to cope with the mental changes that happen.
There is no cure for Alzheimer’s disease, but there are various medications and other strategies which aim to relieve the symptoms and slow down the progression of the disease. Non-drug strategies include memory training or encouraging social activities. You can read more about the treatment options at different stages of the disease here.
Different medications are approved in Germany for treating Alzheimer’s disease, including Axura and Ebixa. Both of these contain the drug memantine. Memantine has been approved for use in mild to moderate Alzheimer’s disease. It aims to prevent an excess amount of the substance glutamate from damaging the brain. Glutamate is a substance that carries nerve signals and helps us to remember things, for example. Researchers have concluded from experiments on animals that people who have Alzheimer’s disease could have a permanent excess amount of glutamate, causing their nerve cells to die. Memantine aims to prevent this without disturbing the normal transmission of nerve signals.
Researchers from the German Institute for Quality and Efficiency in Health Care (IQWiG) together with a group of researchers from the Berlin Institute of Technology (TU Berlin) analyzed whether people who have Alzheimer’s disease benefit from memantine. Among the things the researchers were interested in were the questions of whether the drugs improved mental (cognitive) performance, relieved mental symptoms or helped make managing everyday tasks any easier. They also studied whether the medication influenced the need for care. This analysis also aimed to determine whether memantine can help with these problems better or worse than other drugs such as Ginkgo-based products or cholinesterase inhibitors.
The researchers looked for trials that compared memantine either with a dummy drug (placebo), with other drugs or with non-drug treatments. Only trials that lasted for at least 16 weeks were considered. The researchers were able to find 9 trials meeting these requirements involving a total of about 2,300 participants. All of the trials compared memantine with a placebo. In 2 trials the participants took both before and during the trial another Alzheimer’s drug, a so-called cholinesterase inhibitor. The number of women participating was a bit larger than the number of men; the average participant age in the different trials was between 72 and 85 years. No conclusive trials were found that compared memantine with other drug or non-drug treatments.
Memantine can somewhat delay the deterioration of certain abilities
All trials looked at the effect memantine has on abilities important to situations of daily life, mental performance, and psychological symptoms. Emotional strain on relatives and loved ones was also included in most of the trials. There was not enough data collected on the quality of life for those affected and on the need for nursing and care. This unfortunately leaves many questions unanswered. Yet all of the trials show that the disease’s symptoms usually become worse with time – regardless of whether people took memantine or not.
Limitation of activities of daily life
Abilities important to daily life got worse for all participant groups over the course of the trials. There is evidence from the trials that memantine can delay this process. Teeth-brushing, getting dressed, or taking the bus or subway are all examples of the abilities considered important to daily life.
The trials show that memantine can somewhat delay the deterioration of mental abilities – for example the ability to remember particular things or to learn something. Expressed in numbers, memantine was able to delay the deterioration of mental performance over a time period of 6 months in about 1 out of every 10 people.
Other therapy goals
There is no evidence that people who take memantine are less likely to have mental problems like depression, sleeping disorders or severe restlessness. There is no information in these trials about whether memantine influences how long people with dementia can still be cared for at home. There is little data on mortality – yet they show no effect from memantine on the number of deaths.
There is also no evidence that this treatment helps to lessen the burden on family members or loved ones, for example by lowering the need for care or relieving emotional burden.
There were also no groups for which memantine had a better effect – for instance, people of a certain age or sex, or who had a particular severity of disease.
People who took memantine did not end their participation in the trials early due to adverse effects more often than people who took a placebo. This is a sign that memantine was well-tolerated. Overall, the drug did not lead to adverse effects more often than a placebo, either. Yet too few people participated in the trials to include possible rare adverse effects. Also, participants were in relatively good health, aside from their Alzheimer’s disease. For this reason, it is not clear how safe memantine is for people who are also taking other drugs to treat additional conditions.
Unanswered questions remain
Since none of the trials ran for longer than 6 months, the consequences of long-term memantine treatment remain unclear. IQWiG also did not find any conclusive trials directly comparing memantine either with other drug or non-drug treatments for Alzheimer’s disease. This leaves the question as to whether memantine works as well as, better than or possibly even worse than other drugs or treatments unanswered.
You can find more about treatment options for people with dementia here.
This health information is a summary of a scientific report published by IQWiG. It is not an assessment of the right to have health care services reimbursed by statutory health insurance funds in Germany. By law, decisions about the reimbursement of diagnostic and therapeutic procedures can only be made by the German Federal Joint Committee (G-BA). The Federal Joint Committee takes IQWiG reports into consideration in its decision-making process. You can find information about the decisions of the German Federal Joint Committee on its English-language website, www.english.g-ba.de.
- German Institute for Quality and Efficiency in Health Care (IQWiG). Memantine in Alzheimer’s disease. Final report A05-19C. Version 1.0. Cologne: IQWiG. July 2009.
- German Institute for Quality and Efficiency in Health Care (IQWiG). Memantine in Alzheimer’s disease: Results of the unpublished studies IE2101 and MEM-MD-22 as well as unpublished responder analyses. Working paper. Version 1.0. Cologne: IQWiG. July 2010.
- German Institute for Quality and Efficiency in Health Care (IQWiG). Responder analyses on memantine in Alzheimer’s disease. Commission No. A10-06. Version 1.0. Cologne: IQWiG. March 2011.
Last Update: July 19, 2011.
© IQWiG (Institute for Quality and Efficiency in Health Care)