UPDATE 1-Split US FDA throws Glaxo’s Avandia to panel

* Glaxo trial backing diabetes drug draws sharp critique

* But a top FDA official does not see demonstrable harm

* Shares down 1 percent on NYSE
(Adds details from documents, byline)

By Lisa Richwine and Susan Heavey

WASHINGTON, July 9 (BestGrowthStock) – U.S. drug reviewers are
deeply divided over the heart risks of GlaxoSmithKline Plc’s
(GSK.L: ) (GSK.N: ) diabetes drug Avandia, leaving it to an expert
panel to recommend next week if the drug is too dangerous to
stay on the market.

More than 700 pages of internal documents, released on
Friday, showed some staff at the Food and Drug Administration
believe Avandia may increase the chances of a heart attack but
other officials back its safety.

Glaxo shares were down 1 percent on the New York Stock
Exchange at $34.56 during mid-morning trading.

Glaxo has said a clinical trial called Record shows the
drug is safe for the heart, but an FDA cardiology expert
sharply criticized the study.

The trial “was inadequately designed and conducted to
provide any reassurance about” the cardiovascular risks of
Avandia, said Dr. Thomas Marciniak, a medical team leader in
the FDA division that reviews heart drugs.

He said the findings suggested Avandia increased the
chances of a heart attack and “biases in the study suggest that
the true risk could be higher.”

But Dr. Ellis Unger, a deputy director in FDA’s drugs
center, said “aside from the known risk of heart failure, the
study does not appear to demonstrate harm” from Avandia. The
drug’s warning label already warns of the heart failure risk.

Other FDA staff compared the risks of Avandia and a
competitor, Takeda Pharmaceutical Co’s (4502.T: ) Actos.

An analysis of several clinical trials found major problems
such as heart attacks, strokes or related deaths were lower for
Actos compared with other diabetes drugs or a placebo. They
said, however, that differences in the design of the studies
limited the ability to directly compare Avandia and Actos.

At the panel meeting on Tuesday and Wednesday, the FDA
advisers will consider a range of options for Avandia,
including if the medicine should be pulled from the market over
heart risks.

They also will weigh other possibilities that would allow
Avandia sales to continue. They include restricting the drug’s
use, beefing up warnings or removing a strong heart-attack
warning added in 2007.

European regulators said on Friday they were launching a
new probe into the safety of Avandia, adding to pressure on the
medicine. [ID:nLDE6680IZ]

The FDA and its expert panel must pore over a mass of
studies that have various strengths and weaknesses and provide
conflicting findings about the heart risk. Some FDA staff have
pushed for the drug to come off the market.

“There is not complete unanimity within the FDA about the
interpretation of these data,” Dr. Janet Woodcock, head of the
FDA’s drugs center, told reporters on Thursday.

The FDA usually follows the advice of its expert panels.

Avandia remains widely used but its 2009 U.S. sales of $663
million made up just 1.5 percent of Glaxo’s total revenue.
Investors are more concerned about potential liability for the
British drug giant if Avandia comes off the market rather than
reduced sales.

Controversy has dogged the drug since 2007 when Cleveland
Clinic researchers linked the pill to a higher heart-attack
risk. An advisory panel that year agreed the data suggested
Avandia may increase the chances of a heart attack for some
patients but said the medicine should remain an option.

Glaxo says the overall data shows Avandia does not increase
the overall risk of heart attack, stroke or death and it is the
only oral anti-diabetes drug that has been shown to control
blood sugar for up to five years.

“We look forward to presenting these data and participating
in a rigorous scientific discussion” at the panel meeting,
GlaxoSmithKline Vice President Murray Stewart said in a
(Reporting by Lisa Richwine; Editing by Tim Dobbyn)

UPDATE 1-Split US FDA throws Glaxo’s Avandia to panel