Accelerated Vaccine Dosing Schedule Approved for Japanese Encephalitis

The only vaccine available in the United States for protection against Japanese encephalitis virus just received approval from the US Food and Drug Administration (FDA) for an accelerated dosing schedule.

The inactivated, adsorbed vaccine (IXIARO) is manufactured by Valneva USA, the US subsidiary of Valneva SE.

According to the World Health Organization (WHO), Japanese encephalitis is, “the main cause of viral encephalitis in many countries of Asia (see Map) with an estimated 68,000 clinical cases every year.” Although the virus is rare, when contracted, it can be serious, with a case fatality rate of upwards of 30%. Because there is no cure for the infection, pre-exposure prevention is paramount.

Adults in the United States who are seeking to receive the vaccine prior to traveling to an area where the infection is endemic previously had to wait 28 days between the 2 separate doses of the vaccine to complete the full course. With this new approval, those seeking the vaccine can receive the 2 doses 7 days apart. Of note: “the standard 28-day schedule still applies to children two months to 17 years and adults 66 years and older,” according to a statement on the accelerated schedule approval. Either vaccine schedule must be completed a minimum of 7 days prior to travel to areas where the infection is endemic.

Charles Daily, general manager of Valneva US spoke about the approval in a statement, “The FDA approval of this accelerated 7-day dosing schedule is a positive step toward protecting more people from Japanese encephalitis. For travelers who do seek protection with a vaccine prior to travel, oftentimes they are not aware of the dosing schedule and therefore have not visited their doctor soon enough to allow for two doses. Eliminating this time barrier will make it easier for patients to plan for their travel health needs and to better protect themselves.”