Up to three experimental drugs will be tested to determine if they can be used to prevent the development of Alzheimer's disease. The clinical trials, which are due to start in 2013, will include people at genetic risk of the early-onset form of the disease. Unusually, these trials will focus on preventative treatment, hoping to halt or slow the onset of symptoms, rather than taking the traditional approach of treating symptoms after they develop.
'Trying to prevent Alzheimer's symptoms from ever occurring is a new strategy', says Dr John Morris, the principal investigator at the Dominantly Inherited Alzheimer's Network (DIAN) at the Washington University School of Medicine, USA, which is conducting the trials. There is currently no cure for Alzheimer's disease, and therapies to treat symptoms have had little success so far.
The trials will include two drugs already shown to have some effect on Alzheimer's symptoms. These are gantenerumab, developed by Roche, and solanezumab, developed by Eli Lilly and Company. Potentially, a third drug, a beta secretase inhibitor, also developed by Lilly, may be included.
All three drugs target amyloid beta, the main component of plaques that typically form in the brains of people with Alzheimer's, but in different ways.
'We are excited that this diverse portfolio of drugs and approaches will accelerate the discovery of an effective treatment for Alzheimer's', says Randall Bateman, professor in neurology at Washington University School of Medicine, who is involved in the trials.
The trials will include 160 people carrying early-onset Alzheimer's mutations, but who currently have little or no symptoms of the disease. The early-onset inherited form is not the most common type of Alzheimer's, but people with these mutations are very likely to develop the disease, compared to the general population. Symptoms typically start showing around 30 to 50 years old, and the people chosen to participate in the trial will be within ten to 15 years of their anticipated onset.
Each person will receive one of the three drugs, or a placebo, and they will be monitored for known early biological indicators of Alzheimer's development. Initial trials are expected to last for two years, but will continue and expand if any drug succeeds in halting or significantly slowing the build-up of these biological indicators.
Trials will be conducted in DIAN trial sites around the world, including Europe and Australia.