A new Alzheimer’s drug raises hopes that the disease can be slowed down at an early stage. But the drug can have serious side effects.
Will there be an effective drug against Alzheimer’s soon? The Japanese pharmaceutical company Eisai raised this hope in a press release two months ago. Now finally the scientific evaluation of the clinical study before.
This evaluation shows that for the first time there is a drug that can dissolve harmful deposits in the brains of Alzheimer’s patients and thus better maintain their cognitive performance. But how much this benefits those affected and what side effects they have to reckon with remains unclear.
A little effective – at a high price
Almost 1,800 people took part in the clinical study with the drug lecanemab. All participants were in the early stages of Alzheimer’s disease. Half of them received an infusion of the drug every two weeks, the other half a placebo.
After 18 months it was found that the harmful deposits in the brain – the so-called amyolid plaques – formed a little more slowly when the patients received lecanemab. And this group of patients did a little better on tests that looked at how their brains were performing.
Experts criticize that this very small effect will hardly play a role in the lives of those affected and their families. The manufacturer Eisai also emphasizes that longer studies are important in order to better investigate the long-term effects and risks of the drug.
How much good, how much harm does it do?
Because the effect of lecanemab may have a high price: shortly before the publication of the current study became knownthat a 65-year-old woman had died of a massive cerebral hemorrhage. She had been treated with lecanemab. It has not yet been fully clarified to what extent the drug was responsible for the woman’s death. A few months earlier there was a similar case of an Alzheimer’s patient known. He also received lecanemab.
Many experts consider a connection between lecanemab and cerebral hemorrhage to be quite possible. Lecanemab is what is known as a monoclonal antibody, as are two other promising active ingredients that have recently made headlines: aducanumab from Biogen and gantenerumab from Roche. These antibodies act like a kind of dental floss in the vessels of the brain: in the best case, they manage to dissolve the harmful amyolid deposits – like dirt between the teeth.
Hope despite little progress
But it can happen that the amyolid plaques have already grown into the vessel walls. If they are then dissolved by a drug, it weakens the vessel walls. They can burst and cause a cerebral hemorrhage. This risk is particularly increased if a patient has to take a blood thinning medication.
There are still many problems and challenges that we need to solve
Despite the rather small advances and worrying side effects of lecanemab, many doctors and Alzheimer’s researchers are happy. “There remain many problems and challenges that we need to solve,” said UK Dementia Research Centre’s director, Nick Fox, in a written statement. “But for the many patients it’s better if we have these problems than no perspective at all.”