Striking Alzheimer's Out

Alzheimers vaccine trial yields positive results

(RxWiki News) One of the world's most destructive fatal diseases is one step closer to a possible vaccine following a second trial of a vaccine for Alzheimer's disease.

A very small trial of an experimental vaccine has shown enough success and safety to encourage researchers to continue testing it with a larger group of people.

"See a doctor if you experience unusual loss of memory or disorientation."

Bengt Winblad, MD, PhD, professor of geriatrics at Karolinska Institute's Alzheimer's Disease Research Center in Hugginge, Sweden, led the study to see if the drug, called CAD106, had the hoped-for effect in a group of 58 people.

The aim was for those receiving the vaccine to develop an antibody response to beta-amyloid, a substance that builds up as plaque in the brain and kills brain cells.

It's formed by the breaking down of a protein in the outer membrane of nerve cells, and researchers hope a vaccine that prevents the build-up of beta-amyloid may also stave off Alzheimer's disease.

The study participants, aged 50 to 80, had mild-to-moderate Alzheimer's disease and were split into two groups for a study period lasting a year.

In one group of 31 patients, 24 received 50μg of CAD106 and seven received a placebo. In the second group of 27 patients, 22 received 150μg of CAD106 and five received the placebo.

Neither the patient nor the person giving the injection knew whether the patient was receiving CAD106 or a placebo shot. Each patient received three injections.

In the first group, 67 percent of the patients receiving the vaccine developed the antibody response the researchers were looking for. In the second group, 82 percent of the CAD106-treated participants had the antibody response. One person who received the placebo had the antibody levels as well.

It will require long-term follow-ups to see if the antibody response results in actually reducing or preventing beta-amyloid and whether this prevents the deterioration of the disease.

All but two of the 58 patients reported side effects. The most common one reported in the first group was a cold, and the most common side effect in the second group was redness at the injection site.

Although nine patients reported serious adverse events, none were determined to be caused by the drug.

The researchers concluded that CAD106 appears to be safe so far and leads to an antibody response in a substantial number of those who received the shot.

The study appeared online June 6 in the journal Lancet Neurology. The study was funded by Swiss pharmaceutical company Novartis.

Review Date: 
June 8, 2012