* FDA letter: Company overstated benefits, minimized risks
* Dendreon shares end higher
(Adds company comment, details on product; updates shares)
WASHINGTON Aug 6 Dendreon Corp DNDN.O
exaggerated the benefits of its novel prostate cancer vaccine
and downplayed risks in some sales materials for the product,
U.S. regulators said in a letter released on Friday.
"These promotional materials are false or misleading
because they omit and minimize the risks and overstate the
efficacy of Provenge," the U.S. Food and Drug Administration
said in a letter to the company.
Some of Dendreon's promotions included a chart that "does
not provide sufficient contextual information for the presented
survival rate estimates to convey the limitations of" the
company's main study, the FDA said.
The materials also left out some information about
sterility testing, the agency said.
The FDA asked Dendreon to immediately stop using the
promotions and any others with similar claims.
Dendreon spokeswoman Katherine Stueland said the company
"has spoken with the FDA and intends to comply with the
The FDA approved Provenge in April for treating advanced
Unlike traditional vaccines that prevent a disease,
Provenge treats prostate cancer by stimulating the body's own
immune system to attack malignant cells. It is produced by
taking cells from a patient's tumor and incorporating them into
a vaccine that is injected back into the patient.
Dendreon shares fell slightly after the FDA letter was
released but recovered to close 1.5 percent higher at $39.05 on
The FDA posted the letter here.
(Reporting by Lisa Richwine. Editing by Robert MacMillan,