Etanercept, also known as Enbrel -- used to treat autoimmune diseases such as rheumatoid arthritis -- binds and inactivates excess tumor necrosis factor-alpha, or TNF. Normally, TNF finely regulates the transmission of neural impulses in the brain.

Study authors Dr. Edward Tobinick of the University of California-Los Angeles and Dr. Hyman Gross of the University of Southern California hypothesize that elevated levels of TNF in Alzheimer's disease interfere with this regulation. Excess TNF-alpha has been documented in the cerebrospinal fluid of patients with Alzheimer's.

The article discusses one patient but many other patients with mild to severe Alzheimer's received the treatment and all have shown sustained and marked improvement, the news release said.

The finding are published in the Journal of Neuroinflammation.