Emerging Treatments for Alzheimer's Disease

The battle worth fighting.

Alzheimer's disease will claim 700,000 lives this year. As baby boomers continue to age, the Alzheimer's Association expects these numbers to climb dramatically. Much to the chagrin of experts and the public alike, there are only two classes of medications to treat the disease. "The frustrating thing about these drugs is they don't stop the biology of the disease. They merely delay symptoms, and we need something more potent," says Dr. David Knopman, neurologist and researcher at the Mayo Clinic in Minnesota.

What's available now?

The U.S. Food and Drug Administration approved Aricept in 1996 and Exelon in 2000 for all stages of the disease: mild or early, moderate or middle and severe or late. Razadyne was approved in 2001 for mild-to-moderate Alzheimer's phases. These drugs are known as cholinesterase inhibitors, which work by stalling the breakdown of a chemical messenger responsible for learning and memory. Namenda, approved in 2003, belongs to another class of drugs believed to block the destruction of neurotransmitters in the brain responsible for learning and memory. However, none of the drugs can reverse symptoms.

Lifestyle changes really can help.

Exercise is good for your brain. Really. Science says so. Three separate studies presented at the Alzheimer's Association International Conference in the District of Columbia this summer suggest that regular physical activity may stave off the risk of Alzheimer's disease, mild cognitive impairment and dementia. "We've seen this continuous stream of data that suggests how important things like exercise, nutrition and staying mentally and socially engaged" are to brain health, explains Dean Hartley, director of science initiatives in the division of medical and scientific affairs at the Alzheimer's Association. "The brain is like other parts of the body: You use it or lose it."

Prevention may soon be possible.

"The sophistication of our basic science technologies have increased over the last 20 years," says Knopman, who also serves on the Alzheimer's Association's medical and scientific advisory council. There are currently five clinical trials aimed at preventing the disease before symptoms appear. Within a few years, researchers will know if a preventive treatment could soon be available for Alzheimer's disease, he says.

The A4 study

The A4 study -- Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease -- will test whether the investigational drug solanezumab can slow memory loss caused by Alzheimer's disease. Amyloid is a protein that can build up in the brain, much like plaque does in the arteries. Researchers are aiming to treat patients before they have symptoms, "because if we're treating once they have symptoms, it might be too late," says Dr. Marwan Sabbagh, of the Banner Sun Health Research Institute and a professor of neurology at the University of Arizona College of Medicine in Phoenix. The LEARN study will expand upon the findings from the A4 study.

The DIAN study

The DIAN study -- Dominantly Inherited Alzheimer Network -- is currently enrolling those with a strong family history of Alzheimer's disease that is passed down every generation, Knopman says. This type only accounts for 1 percent of Alzheimer's disease cases. Those who are included in the study will be treated with one of two experimental drugs to determine if these medications can prevent, delay or possibly reverse Alzheimer's disease changes in the brain, Knopman says.

The API trials

The Alzheimer's Prevention Initiative involves two trials. The APOE4 Treatment Trial began this year and is looking at using the body's own immune system to protect against the buildup of harmful proteins or other chemicals in an effort to delay or prevent the onset of Alzheimer's disease. The Autosomal Dominant Alzheimer's Disease Treatment Trial began in 2013, investigating how the experimental drug crenezumab might delay or prevent symptoms in healthy individuals who carry a gene for the disease.

The TOMMORROW study

The TOMMORROW study is recruiting individuals ages 65 to 83 in good physical and mental health for a nationwide study that will evaluate the effectiveness of a newly developed test to determine a person's genetic risk for getting mild cognitive impairment due to Alzheimer's disease. The study will also examine whether an investigational medication, pioglitazone, will delay the early symptoms of mild cognitive impairment in study participants, according to the Alzheimer's Association.

Samantha Costa is a Health + Wellness reporter at U.S. News. You can follow her on Twitter, connect with her on LinkedIn or email her at scosta@usnews.com.