Study to test antibody crenezumab for preventing Alzheimer's
By Janice Lloyd, USA TODAY
Updated 5/15/2012 9:52 PM
BETHESDA, Md. – The government will launch a first-ever collaborative, multimillion-dollar drug trial to try to prevent a form of Alzheimer's disease, officials said during a two-day research summit at the National Institutes of Health here.
"This is the beginning of a new era of Alzheimer's research," says Eric Reiman, a researcher for Banner Alzheimer's Institute in Phoenix, which is partnering with the National Institutes of Health, drugmaker Genentech and the University of Antioquia in Medellín, Colombia.  "It's so exciting to be able to conduct the first prevention trial that might be able to help families fight against this disease, which they regard as a curse, and to help the world."
Francis Collins, director of the NIH, says  the government is committing $16 million to the $100 million prevention trial and an additional $7.9 million to a second trial for treating Alzheimer's disease. The trials launch the government's ambitious national plan to find a cure by 2025.
Signed into law last year by President Obama, the plan went through several drafts before Health and Human Services Secretary Kathleen Sebelius presented a final version Tuesday. The plan calls for new research, earlier diagnosis, new training for physicians to detect the disease and help for caregivers.
 At the heart of the plan are the 5.4 million people in the USA affected by the incurable brain-wasting illness, and a smaller segment of about 200,000 who have the more rare form of early-onset Alzheimer's. Those numbers are expected to triple by 2050 as Baby Boomers get older. "With the good news of living longer comes additional challenges," says Sebelius. "As we live longer, we face health challenges that weren't evident before. And one of the biggest challenges is Alzheimer's disease."
 The purpose of the collaborative prevention trial is to find out if an experimental antibody called crenezumab can sustain memory and cognitive skills in people who are genetically disposed to get the disease at a young age. If it proves to be effective, Reiman says, the study could provide a faster way to test future Alzheimer's therapies. It can take 15 to 20 years to bring an experiment from trial to the consumer, and by then, Reiman says, "more generations will be lost to this devastating disease."
While a slice of the trial will be held in the USA, its primary focus is on an extended family of 5,000 members in Medellín, Colombia, that has a genetic predisposition for early-onset Alzheimer's. Not all forms of Alzheimer's have the genetic predisposition, but members of this family exhibit symptoms in their mid-40s and can have advanced Alzheimer's by their early 50s.
The trial will be conducted on about 300 family members who are in their 30s and have the gene for early-onset Alzheimer's but have not yet shown symptoms.
Most trials do not find cures, but Laurie Ryan of the National Institute on Aging says the timing of this trial follows others that have advanced the understanding of how the disease progresses. For instance, ongoing trials expected to finish this summer are looking at the effect of antibodies in people who have mild cognitive impairment and are in the early stages of Alzheimer's.
"This is a groundbreaking look at cognitively normal individuals, yet a look at people we know will get the disease," says Ryan, program director for the NIA's Alzheimer's Disease Clinical Trials program. "New research is telling us earlier intervention is better."
 The antibody's mission is to prevent or stall amyloid plaques from forming in the brain. Amyloid plaques and tangles — irregularities that form in brain neurons after amyloid plaques appear — both create havoc with brain synapses. Researchers compare this antibody's effort to how statins prevent bad cholesterol from damaging the heart.
In animal studies, Reiman says, researchers have learned that therapy needs to be started before tangles form. "If you start after the tangles form, you can not stop the disease," he says.
Both metabolism and inflammation also seem to play roles in Alzheimer's.
 The second trial NIH is funding will test a nasal spray for treating Alzheimer's. Suzanne Craft performed a small pilot study at the University of Washington showing that insulin sprayed directly into the brain might slow the disease. Brain cells need insulin, which provides glucose, a form of food for brain cells, Craft says.
"The preliminary trial was promising," says Craft. "Memory improved, and the caregivers' perceptions of their loved ones' functional skills were encouraging as well."
Current treatments do very little to help Alzheimer's patients. The last drug was discovered in 2003.
About 600 researchers took part in the summit, the largest group ever assembled on Alzheimer's. One of Tuesday's segments discussed non-pharmalogical ways to prevent or slow the disease. The Mediterranean diet, aerobic exercise and weight training in later life were hailed as other interventions that might help slow the disease.
"The goal is to make our brain spans equal our life spans," says George Vradenburg, chairman of UsAgainstAlzheimer's and a member of the advisory council for the national plan. "I think it's a monumental shift we're making by looking at prevention. We're off to a good start."