The Food and Drug Administration (FDA) has expanded the use of Adacel (tetanus toxoid, reduced diphtheria toxoid and acellular pertussis [Tdap] vaccine adsorbed; Sanofi Pasteur) to allow for repeat vaccination in patients 10–64 years old ≥8 years after the first Tdap vaccination. Adacel is approved for active booster immunization against tetanus, diphtheria, and pertussis.

The approval was based on data from the Td537 study which included individuals 18–64 years old who had received a dose of Adacel 8–12 years prior (N=1330). Participants were randomized to receive either a second dose of Adacel (N=1002) or Td vaccine (tetanus and diphtheria toxoids adsorbed; N=328). Blood samples for immunogenicity analyses were obtained from participants pre-vaccination and approximately 28 days post-vaccination.

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Results showed that a second dose of Tdap vaccine was found to be both immunogenic and well-tolerated. According to Sanofi Pasteur, the results from this trial have been submitted to the Centers for Disease Control and Prevention (CDC)’s Advisory Committee on Immunization Practices (ACIP) for consideration in future vaccine recommendations.

“The licensure of Adacel as the first Tdap vaccine in the US for repeat vaccination is an important step for eligible patients and offers flexibility for healthcare providers to help manage their immunization schedules,” said David P. Greenberg, MD, Regional Medical Head North America at Sanofi Pasteur.

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