Problem with Current Drugs
At the present time there is no drug on the market for AD that targets the underlying nerve cell degeneration. All of the drugs currently marketed for AD try to increase neurotransmitter receptor function. These drugs have potentially serious side effects without any significant proven benefit. In fact, the National Institute for Clinical Excellence, the independent body that recommends which medical therapies the National Health System provide in England and Wales, has proposed that donepezil, rivastigmine, galantamine, and memantine no longer be used to treat AD (Sullivan, 2005).
In addition, the Food and Drug Administration (FDA) on April 11, 2005 issued a public health advisory for atypical antipsychotic usage in elderly patients with behavioral disturbances. The FDA determined that the treatment of behavioral disorders in elderly patients with dementia with atypical (second generation) antipsychotic medication is associated with an approximately 1.6-1.7 fold increase in mortality. Most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infection (e.g., pneumonia) in nature. Of a total of seventeen placebo controlled trials performed with olanzapine (Zyprexa), aripiprazole (Abilify), risperidone (Risperdol), or quetiapine (Seroquel) involving 5,106 patients, fifteen studies showed numerical increases in mortality (1.6-1.7 times) in drug-treated patients compared to the placebo-treated patients. Because of these findings, the FDA has asked the manufacturers of these drugs to include a Boxed Warning on their labeling describing this risk and noting these drugs are not approved for this indication.