There is a new drug for treatment of Alzheimer's. How effective is it?

Nearly two months after pharma companies Eisai and Biogen announced the discovery of a drug lecanemab, which slows the progression of Alzheimer's disease in patients, a new research finding shows that the drug indeed slows cognitive decline in people.  

It has been found that the drug works during the early stages of the disease, and it showed promising results on 1,795 volunteers who had undergone the large-scale trial of the drug.

How lecanemab works? The drug lecanemab is an antibody that attracts the immune system of the body to attack the amyloid protein, which is the main cause of the Alzheimer's, and clear it off from the brain.

• Amyloid protein clumps together in the spaces between the neurons in the brain and forms distinctive plaques that are also one of the hallmarks of Alzheimer's disease.
• The drug which is given intravenous to the patient works by collecting around the brain neurons.
• The drug sticks to the amyloid protein in the brain and then it attracts the immune cells to break down the protein.
• Professor John Hardy, who is one of the world's foremost researchers and the one who actually started the research to go after amyloid protein 30 years ago, has called it a "historic" development. He said that "we're seeing the beginning of the Alzheimer's therapies". Professor Tara Spires-Jones, from the University of Edinburgh said that the results were "big deal because we've had 100% failure rate for a long time."

How effective will the drug be?

• Though the drug acts slowly, but the doctors are saying that those getting the drug are 0.45 better off.
• Dr Elizabeth Coulthard, who treats patients at North Bristol NHS Trust, says that people have on average, six years of living independently once mild cognitive impairment starts.
• Slow that declines by a quarter and it could give an extra 19 months of independent life to the patient, "but we don't know that yet", she said.
• The researchers have also said that the drug starts working in the initial stages of the Alzheimer's.
• Now, this also requires the people to come for early tests in cases of memory loss and doctors sending them for the amyloid tests to ascertain whether they have Alzheimer's or another form of dementia.

What are the side effects reported? Hold on, there are some side effects of the drug too. The brain scans of people who underwent trial showed that nearly 17% of the people showed a risk of brain bleed while 13% showed brain swelling. Overall, 7% of the people had to stop because of the side effects.

What is Alzheimer's disease? It is a progressive disease that destroys memory and other important functions of the brain.

It is a type of dementia that affects memory, thinking and behavior. The disease accounts for nearly 60-80% of the dementia cases.

Symptoms: The most common symptom of Alzheimer's is difficulty in recalling newly learned information. 

• As the disease progresses, symptoms such as mood and behaviour changes, deepening confusion about events, time and place, unfounded suspicions about family, friends,, serious memory loss and behavior changes are some early symptoms of the disease.
• On an average, a person diagnosed with Alzheimer's lives 4-8 years after diagnosis but can live as 20 years depending upon other factors. 
• In India, nearly 5 million people are affected by Alzheimer's.