12 in Alzheimer Vaccine Trial Seriously Ill With Brain Inflammation

A month after suspension of trials of the experimental Alzheimer's vaccine AN-1792 (see earlier Alzheimer Week story), 12 participants in the study are now reported seriously ill with brain inflammation.

While officials of Elan, the manufacturer of the drug, have released little information, The Washington Post reported that sources familiar with the study said there is little question the vaccine triggered the brain reactions, which some called encephalitis (an inflammation of the brain) and another called "meningoencephalitis," an inflammation of the brain and surrounding membranes.

Both syndromes can cause symptoms ranging from fever, headache and vomiting to altered consciousness, muscle weakness and seizures.

Approximately 360 people with mild to moderate Alzheimer's disease had been enrolled in the study of AN-1792, which researchers had optimistically hoped could halt the progression of or even cure Alzheimer's disease.

Elan, when it first reported the emerging problem in January, noted that four patients in the high-profile study had "clinical signs consistent with inflammation in the central nervous system," and that further dosing of patients in the multicenter international trial had been "temporarily suspended."

Since then, the number has climbed to 12 at several test sites, The Post reported.

"The company can confirm there have been a number of additional cases of adverse events identified," an Elan spokesman later said.

"I think everyone is puzzled" about why the problems happened, said Marilyn Albert, a researcher at Massachusetts General Hospital, ho heads the Alzheimer's Association's medical and scientific advisory council. But Albert said that in all likelihood, "they can't go forward with this formulation."

Other sources: Washington Post