Pfizer''s Lipitor has no effect on Alzheimer''s disease

According to the Associated Press, drug developer Pfizer Inc. said recently that adding its cholesterol drug Lipitor to the Alzheimer''s disease treatment Aricept had no impact on Alzheimer''s patients.

The combination of 80 milligrams of Lipitor with Eisai Co.''s Aricept neither improved nor worsened cognition in the 18-month study of 640 patients. The drug combination was compared with a regimen of Aricept and placebo.

The study results were presented at the annual American Academy of Neurology meeting in Chicago.

Lipitor is the world''s best selling drug and Pfizer''s biggest revenue driver. Its patent will expire in 2010, opening the door for generic competition and possibly cutting billions of dollars annually in revenue for Pfizer.

Sales of the drug are already on the decline, shedding 7 percent to reach $3.14 billion in the first quarter.