Jul 21, 2009 (CIDRAP News) – The Food and Drug Administration (FDA) yesterday announced its approval of seasonal influenza vaccines for this year, the annual step that clears the way for manufacturers to start marketing their vaccines.
Six manufacturers are making seasonal flu vaccines for the US market this year—five inactivated injectable vaccines and one live attenuated vaccine given as a nasal spray. The FDA recently sent all six companies letters approving their supplemental license applications for this year's version of the vaccine.
The seasonal vaccine targets three influenza subtypes; the specific strains are often changed from year to year as health authorities strive to keep up with the strains in circulation. This year's vaccine contains a different influenza B component than the 2008-09 vaccine. The type A/H1N1 and A/H3N2 components are the same as in last year's version.
The manufacturers must obtain a release from the FDA for each lot of vaccine before they can ship it to distributors. FDA spokeswoman Peper Long said the agency has not yet announced any lot releases.
Donna Cary, a spokeswoman for Sanofi Pasteur, which has been the largest supplier to the US market in recent years, said, "We anticipate we'll begin shipping [vaccine] in August, but it all depends on the timing of lot release from the FDA."
In announcing approval of the seasonal vaccines, the FDA was careful to note that they will not protect against the novel H1N1 virus now circling the globe. The government hopes to have the first doses of vaccine for that virus this fall, possibly in October.
Although the seasonal vaccine will not shield people from the pandemic virus, "it is still important for those Americans for whom it is recommended to receive the seasonal influenza vaccine," the FDA announcement said.
In a question-and-answer bulletin posted yesterday, the Centers for Disease Control and Prevention (CDC) indicated that clinical trials will be conducted to determine if seasonal and novel H1N1 vaccines will be safe and effective if given at the same time, though the seasonal vaccine will be available earlier.
The manufacturers supplying inactivated vaccines this year, and their vaccines, are CSL Limited, Afluria; GlaxoSmithKline (GSK) Biologicals, Fluarix; ID Biomedical Corp. (a dvision of GSK), FluLaval; Novartis Vaccines, Fluvirin; and Sanofi Pasteur, Fluzone. The live vaccine, FluMist, is made by MedImmune Vaccines.
Cary said the B strain this year posed some production problems, but Sanofi was able to meet its production target.
"The new B strain this year is a lower yielding strain," she said. "For Sanofi Pasteur we had taken that into account, and we're bringing to market what we promised we'd bring to market"—50 million doses.
In evaluating seasonal vaccines that involve only a strain change, the FDA inspects vaccine lots and production facilities but does not require new clinical data, said Long. "We test lots and production facilities all along the way, it's one of the most important things we do. But it doesn't require new clinical data every year," which wouldn't be possible to provide in the time available, she said.
Jul 20 FDA announcement
CDC question-and-answer bulletin
Feb 18 CIDRAP News story "FDA panel endorses new B strain for 2009-10 flu vaccine"