The U.S. Food and Drug Administration announced Nov. 20 the approval of Flucelvax, the first seasonal influenza vaccine licensed in the United States produced using cultured animal cells, instead of fertilized chicken eggs. Flucelvax is approved to prevent seasonal influenza in people ages 18 years and older.

The manufacturing process for Flucelvax is similar to the egg-based production method, but a significant difference is that the virus strains included in the vaccine are grown in animal cells of mammalian origin instead of in eggs. Cell culture technology has already been in use for several decades to produce other U.S. licensed vaccines.

“Today’s approval represents the culmination of efforts to develop a seasonal influenza vaccine using cell culture as an alternative to the egg-based process,” said Karen Midthun, M.D., director of the FDA’s Center for Biologics Evaluation and Research.

Cell culture technology is another manufacturing alternative to conventional egg-based influenza vaccine production. Advantages of cell culture technology include the ability to maintain an adequate supply of readily available, previously tested and characterized cells for use in vaccine production and the potential for a faster start-up of the vaccine manufacturing process in the event of a pandemic.

Flucelvax was evaluated in a randomized controlled clinical study conducted in the United States and Europe that involved about 7,700 people ages 18 to 49 years who received either Flucelvax or a placebo. The study showed that Flucelvax was 83.8 percent effective in preventing influenza when compared to placebo. The use of Flucelvax in people older than 49 is supported by antibody responses in about 1,700 adults which showed it to be comparable to Agriflu, an egg-based seasonal influenza vaccine approved by FDA for use in people 18 years and older.

The safety evaluation included about 6,700 individuals who received Flucelvax in controlled clinical studies. Injection site and general reactions to Flucelvax were typical of those seen with current influenza vaccines. Pain, redness and soreness at the injection site and headache and fatigue were the most common reactions.

Getting vaccinated each year remains one of the best ways to prevent seasonal influenza. The Centers for Disease Control and Prevention recommends that everyone 6 months of age and older receive an annual influenza vaccine.

Flucelvax is manufactured by Novartis Vaccines and Diagnostics GmbH, Marburg, Germany.