The Food and Drug Administration (FDA) approved a next-generation flu vaccine on Wednesday that is made by injecting flu genes into an insect virus and growing it in caterpillar cells. Federal officials say the first-of-its-kind bug-based vaccine will be used immediately in people willing to test it. It has been approved for use in adults between the ages of 18 to 49.
About 150,000 doses of the vaccine, called Flublok, have been produced and will be distributed in February to those with egg allergies, including others who are unable to receive current flu vaccines, said Manon Cox, who is president and CEO of Protein Sciences Corp., which is the company that came up with the new manufacturing process.
"We've collected names and we'll see what we can do to help," said Cox.
According to a statement released by the FDA, Flublok's unique manufacturing technology allows for production of large quantities of the flu virus protein known as hemagglutinin (HA), which is the active ingredient in all inactivated flu vaccines required for entry of the virus into cells in the body. Most of the antibodies that prevent infection are directed against HA.
"This approval represents a technology advance in the manufacturing of an influenza vaccine," said Dr. Karen Midthun, director of the FDA's Center for Biologics Evaluation and Research. "The new technology offers the potential for faster start-up of the vaccine manufacturing process in the event of a pandemic, because it is not dependent on an egg supply or on availability of the influenza virus."
In current vaccines, the virus has to be isolated from patients' blood and purified before injecting it into specific kinds of chicken eggs to grow. However, with the Flublok technology, such time-consuming steps are avoided; thus, creating a faster and easier to control process that can be scaled up in an emergency.
Flubok was tested in about 2,500 people, but the FDA rejected it for approval the first time around in 2009, instead asking the company to provide more safety data.
With the FDA’s approval of Flubok on Wednesday however, those who were previously unable to receive flu shots, such as those with egg allergies, will now have an added tool to help protect themselves from influenza-like-illness. The most commonly reported adverse events of Flubok included pain at the injection site, headache, fatigue and muscle aches. Side effects that also are common in egg-based vaccines.
The new vaccine comes on the heels of a national flu outbreak that has spread across 90 percent of the U.S., with deaths reaching epidemic levels, according to the Centers for Disease Control and Prevention.