Tdap Booster Vaccine Receives Expanded FDA Indication

Sanofi Pasteur’s Adacel Tdap (tetanus toxoid, reduced diphtheria toxoid and acellular pertussis) absorbed vaccine has been granted expanded indication by the U.S. Food and Drug Administration (FDA) to include repeat vaccinations for tetanus, diphtheria and pertussis. With this expanded indication, Adacel is the first and only Tdap vaccine approved for repeated dose in people ages 10 years to 64 years, eight years or more after their first vaccination, in the U.S. It is also currently the only Tdap vaccine available in a syringe made without natural rubber latex, in the event of a patient allergy.

The expanded indication was based on a clinical trial that involved 1,300-plus adults ages 18 years to 64 years that compared the vaccine to a tetanus-diphtheria (Td) vaccine eight years to 12 years after a previous dose of Adacel. Trial results showed a second dose of the investigative vaccine in adults was associated with no significant difference in adverse events compared to the Td vaccine group. Among the 999 Tdap vaccine patients, 87.7 percent reported at least one injection-site reaction, compared to 88 percent of the Td vaccine recipients.

“In the United States, people who received their first Tdap vaccine dose as an adolescent are now approaching the age at which they are recommended to receive a decennial Td vaccine booster,” investigators wrote. “Some providers might find it convenient or necessary (e.g., because of the availability of vaccine or during an outbreak) to give such a booster as Tdap.” However, the investigators noted that “although the results provide reassurance about the safety and tolerability of and immunogenicity conferred by repeat Tdap booster doses, advisory committees still need to determine the optimal interval for booster doses by using data provided by routine pertussis surveillance and outbreak evaluations.”