Big Pharma giant GlaxoSmithKline (NYSE:GSK) announced in a press statement earlier this week that the Food and Drug Administration has approved  its Fluarix Quadrivalent flu vaccine for adults and for children 3 or older. The company expects the vaccine to be available for the 2013-2014 flu season.

The vaccine will cover both  subtype A and B flu strains and is the first intramuscular  vaccine to cover four different flu strains. Typically, health-care providers order flu vaccines about a year before flu seasons occur.

Leonard Friedland,, vice president and head of GlaxoSmithKline's North America Vaccines and Clinical Development and Medical Affairs branch, said in the  release that "in six of the last 11 flu seasons, the predominant circulating influenza B strain was not the strain that public health authorities selected" and that "Fluarix Quadrivalent will help protect individuals against both B strains and, from a public-health standpoint, can help decrease the burden of disease."

GlaxoSmithKline faces a large, untapped market for flu vaccines. Typically, less  than 50% of individuals receive flu vaccines; the Centers for Disease Control target a rate of 80%.

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