Flublok is a pure protein vaccine manufactured using modern technology that does not contain unnecessary ingredients like egg proteins, gluten, gelatin, latex, preservatives, influenza virus, formaldehyde, or antibiotics. Plus, we include more of the protective ingredient in each vaccine.
Clinical data has demonstrated that Flublok effectively protects people from getting the flu. In fact, in a recent clinical study of 9000 adults comparing quadrivalent Flublok to a traditional, egg-based quadrivalent vaccine, 31%-45% more people were protected from the flu when they received Flublok.
Traditional flu vaccines are still made by injecting live influenza virus into live chicken eggs, where the virus multiplies, a process established 70-years ago. The virus is then inactivated and used to produce the vaccine. However, some influenza viruses do not grow very well in chicken eggs, so the virus changes. These changes can result in a vaccine that does not match the influenza viruses circulating among people and can lead to an ineffective vaccine1.
Rather than grow an influenza virus, we use modern technology to make only the single protein from the influenza virus that is needed for protection. This protein is called the hemagglutinin, or HA, protein. Because we do not grow live influenza virus, our vaccine matches the influenza viruses circulating among people. Each Flublok dose contains HA proteins that match the flu viruses circulating during a given year, so that you are maximally protected.