ALZHEIMERS
1. Context
The news of the success of a drug to reduce cognitive decline in patients with Alzheimer's disease burst on the horizon with all the promise of being a silver bullet. The drug, lecanemab, jointly developed by pharma companies Biogen and Eisai, was tested on patients with early Alzheimer's.
2. Alzheimer's Disease
- The disease is named after Dr. Alois Alzheimer. Dr. Alzheimer observed alterations in the brain tissues of a woman who had passed away from an uncommon mental disease in 1906.
- Memory loss, linguistic difficulties, and unpredictable conduct were some of the symptoms. He examined her brain after she passed away and discovered several aberrant aggregates (now known as amyloid plaques) and twisted fiber bundles (now called neurofibrillary, or tau, tangles).
- These plaques and tangles in the brain are still considered some of the main features of Alzheimer's disease. Another feature is the brain's loss of connections between nerve cells (neurons). Neurons transmit messages between different parts of the brain, from the brain to muscles and organs in the body.
- This damage initially occurs in parts of the brain involving memory, including the entorhinal cortex and hippocampus. It later affects areas in the cerebral cortex, such as those responsible for language, reasoning, and social behavior.
- Eventually, many other areas of the brain are damaged.
3. Cure and Treatment for Alzheimer's disease
- Currently, there is no cure for Alzheimer's disease, though there has been significant progress in recent years in developing and testing new treatments.One treatment aducanumab is the first therapy to demonstrate that removing amyloid, one of the hallmarks of Alzheimer's disease, from the brain is reasonably likely to reduce the cognitive and functional decline in people living with early Alzheimer's.
- Other treatments can temporarily slow the worsening of dementia symptoms and improve the quality of life for those with Alzheimer's and their caregivers. Today, a wonderful effort is underway to find better ways to treat the disease, delay its onset, and prevent it from developing.
- A new drug named Lecanemab that reduces cognitive decline in patients with early Alzheimer's has been discovered. It is one of the first neuroprotective treatments for the disease.
4. Lacanemab
- Lecanemab belongs to a class of drugs called monoclonal antibodies. These antibody-mediated drugs target beta-amyloid, the protein deposition that is seen in patients with Alzheimer's disease, and disrupts cell function.
- As per the NEJM paper, the clinical phase 3 trial involved persons 50 to 90 years of age with early Alzheimer's disease (mild cognitive impairment or mild dementia due to Alzheimer's disease) with evidence of amyloid deposition. Participants were randomly assigned intravenous lecanemab or placebo. It was observed that lecanemab "robustly removed the amyloid plaques". This was the primary endpoint of the trial, which showed a change in the score recorded at baseline when the trial began on the clinical Dementia Rating-sum of Boxes (CDRSB).
- Key secondary endpoints included a change in the amyloid burden on PET (Positron emission tomography).
5. The Future
An initial decision on the drug's approval by the FDA is expected by January 6, 2023, and from the European Medicines Agency later in 2023, according to The Lancet.
For Prelims:
| For Prelims: Lecanemab, PET (Positron emission tomography), Clinical Dementia Rating-sum of Boxes (CDR-SB), Companies Biogen and Eisai, Dementia. |
Source: The Hindu
