FDA staff says Novartis drug works for Parkinson’s

By Susan Heavey

WASHINGTON (Reuters) – An Alzheimer’s drug made by Novartis
Pharmaceuticals effectively treats dementia in patients with
Parkinson’s disease, but it is unclear if such mental
impairments are two distinct conditions, U.S. Food and Drug
Administration staff said on Tuesday.

An FDA statistical reviewer said data showed the drug,
Exelon, effective for the proposed new use. But in a separate
memo, FDA staffers in general questioned whether the company’s
results established that dementia in Parkinson’s patients is
not simply underlying Alzheimer’s disease.

Both documents were released ahead of an FDA advisory panel
meeting on Wednesday to discuss Novartis’ request to promote
Exelon more widely. It is the first application seeking
approval for a drug to treat worsening memory and other mental
problems in Parkinson’s patients, according to the FDA.

The agency wants advice from experts on its advisory panel,
then is expected to make a final decision later this year.

About 1.5 million Americans have been diagnosed with
Parkinson’s, which attacks the nervous system and causes
tremors and other symptoms. Mental problems affect about 40
percent of them.

Alzeimer’s, the most common form of dementia, is a
degenerative brain disease that affects at least 4.5 million
Americans.

“It is not totally unexpected (that) a drug that is
effective for Alzheimer’s disease should work for PD
(Parkinson’s disease) related dementia as well,” the FDA
statistician said.

Data also supported long-term effectiveness.

Research shows increasing reports of dementia with
Parkinson’s, FDA staff said, but it is unclear whether it is
can be diagnosed separately from underlying Alzheimer’s.

“The main question that needs to be addressed in the
context of this application is whether the results … justify
the approval of that drug for ‘dementia associated with
Parkinson’s Disease’ as a separate indication,” FDA staff in
the Division of Neurology Products wrote to the advisory
committee panelists.

In another review, a clinical FDA staffer declined to make
a recommendation until after the panel meeting. The clinician
said reports of nausea, vomiting and tremors were higher in
those taking the drug compared with those on placebo.

Effectiveness of the drug was statistically significant,
the clinician also said.

Exelon, known generically as rivastigmine tartrate, was
approved in 2000 to improve memory and thinking in Alzheimer’s
patients.

Novartis, in separate documents, said its data and other
medical evidence showed Parkinson’s related dementia is a
distinct disease. Its study offers “compelling evidence that
Exelon therapy meets a currently unmet medical need,” it said.

Shares of the Switzerland-based drugmaker were up $1.06, or
nearly 2 percent, at $57.38, in midday trade on the New York
Stock Exchange.

Exelon generated sales in 2004 of $422 million, while 2005
sales were estimated at $480 million.

The documents were posted on the FDA’s Web site at

http://www.fda.gov/ohrms/dockets/ac/06/briefing/2006-4216B1-00-i

ndex.htm