"NEW YORK, Jan 9 (Reuters) - U.S. health regulators have again withheld approval for the use of Merck & Co Inc's (MRK.N) Gardasil cervical cancer vaccine by women aged 27 to 45, asking for longer-term clinical data, the drugmaker said on Friday. The U.S. Food and Drug Administration recommended Merck submit data when a 48-month study on a test group has been completed. The agency also withheld approval in June on Merck's initial application that was based on data collected through an average of 24 months.
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"Gardasil's efficacy drops sharply once females have been exposed to HPV and this is probably the genesis of the problem with the older female population that Merck has been pushing for in this new application," Sanford Bernstein analyst Tim Anderson said in a research note."
http://money.cnn.com/news/newsfeeds/articles/djf500/200901091059DOWJONESDJONLINE000637_FORTUNE5.htm
"In 2007,
The study measured only incidents caused by the targeted HPV strains that weren't already present in women at the start of the study or during the dosing regimen. The vaccine is given in three doses over six months.
In comparison, an earlier study in females aged 16 to 23 showed Gardasil reduced these incidents by 96% versus placebo."