Antibodies show promise in treating Alzheimer's

Jul 19 2006

Researchers say infusing human antibodies into people with Alzheimer's disease appears to help stop the disease from getting worse and may even help the patients improve.

A research team at New York-Presbyterian Hospital/Weill Cornell Medical Center gave six of eight patients intravenous immunoglobulin or IVIg for 18 months and they appeared to develop better brain function.

Dr. Norman Relkin, who led the study says the results suggests that IVIg can exert long-term benefits for the treatment of cognitive decline in Alzheimer's.

The most common form of dementia among older people is Alzheimer's disease (AD) and an estimated 12 million people worldwide are affected.

Scientists estimate that as many as 4.5 million Americans suffer from AD; the disease usually begins after age 60, and the risk increases with age.

While 5 percent of men and women ages 65 to 74 have AD, almost half of those age 85 and older may have the disease.

Alzheimer's is however not a normal part of the aging process.

Alzheimer's initially involves the parts of the brain that control thought, memory, and language and the brains of victims become clogged up with plaques of amyloid proteins and tangles of nerve fibres, but it is still unclear if they are the cause of the disease or a symptom.

Scientists also have found other brain changes in people with AD.

Nerve cells die in areas of the brain that are vital to memory and other mental abilities, and connections between nerve cells are disrupted.

There also are lower levels of some of the chemicals in the brain that carry messages back and forth between nerve cells and impair thinking and memory by disrupting these messages.

The initial stage of the disease is characterised by mild cognitive impairment or memory loss, but as the disease progresses symptoms are more noticeable and forgetfulness begins to interfere with daily activities.

People in the middle stages of may forget how to do simple tasks such as brushing their teeth or combing their hair and can no longer think clearly.

They often do not recognize familiar people and places and begin to have problems speaking, understanding, reading, or writing.

Alzheimer's patients may become anxious or aggressive, or wander away from home and eventually, patients need total care.

Dr. Relkin said his team tested the patients' spinal fluid for amyloid protein and found levels were reduced by more than a third over 18 months and says this indicates the movement of amyloid out of the central nervous system and into the blood stream, where it can be cleared from the body.

IVIg is a mixture of human antibodies, which attach to various foreign invaders such as bacteria and viruses, but also to abnormal cells and proteins and has apparently been used for more than 30 years for a range of disorders.

A major breakthrough is badly needed in new therapies to reduce the disability and suffering of Alzheimer's, and control costs in treating dementia as the world's population is growing rapidly larger and older, and Alzheimer's diagnoses are destined to sharply increase.

The researchers presented their study at the International Conference on Alzheimer's Disease and Related Disorders in Madrid.