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By Ben Hirschler
LONDON, June 23 (Reuters) - AstraZeneca said itwould take an $80 million writedown on stocks of its flu vaccineFlumist Quadrivalent, which is sprayed into the nose, after U.S.health authorities decided they would not use the product.
The U.S. Centers for Disease Control and Prevention (CDC)ruled the vaccine should not be used in any setting, based onU.S. data indicating a marked drop in effectiveness in childrenover the last three years.
The decline in Flumist's efficacy in the United States ispuzzling, especially since CDC experts had recommended itpreferentially in 2014 over injectable flu vaccines in children,citing its superior efficacy.
Flumist is often given to children because they can beimmunised without the need for injections.
AstraZeneca said the CDC data contrasted with its ownstudies as well as preliminary independent findings by publichealth authorities in other countries suggesting the vaccine was46 to 58 percent effective overall against flu strains duringthe 2015-2016 season.
U.S. sales of Flumist in 2015 totalled $206 million, or justunder 1 percent of group revenue.
"AstraZeneca is working with the CDC to better understandits data to help ensure eligible patients continue to receivethe vaccine in future seasons in the U.S.," AstraZeneca said ina statement on Thursday.
"The distribution and use of the vaccine in other countriesare progressing as planned for the forthcoming influenza season,pending the annual release process from relevant regulatoryauthorities."
Despite the setback, AstraZeneca said it maintained its 2016financial outlook of a low-to-mid single digit decline inrevenue and core earnings, at constant exchange rates.
However, Deutsche Bank analyst Richard Parkes said the U.S.vaccine problem would likely drag down consensus earningsforecasts for the current year by around 2 percent and there wasa 1-2 percent risk to future forecasts, if the issue was notresolved.
Shares in AstraZeneca lagged a firmer European market,gaining 0.5 percent by 0940 GMT, while the European drugs sector rose 1 percent. (Reporting by Ben Hirschler; Editing by Jason Neely and SusanFenton)
