In October 2010, the Advisory Committee on Immunization Practices (ACIP) issued a new recommendation for Tdap vaccination — the booster vaccine that provides protection against tetanus, diphtheria, and pertussis (whooping cough). While the vaccine had previously been recommended as a one-time booster for adults up to age 64, replacing an individual tetanus booster, the committee voted to expand that recommendation: anyone older than 65 who had not received a prior dose of Tdap should receive one if they expected to have close contact with an infant younger than 12 months old.
This recommendation was made partially in light of the California whooping cough epidemic. While whooping cough is typically less severe in adults, the infection can still be passed to infants, for whom infections are much more severe. Study data has indicated that grandparents, for example, are the ultimate source of the infection in 6-8% of cases. However, the committee noted that there was a direct benefit to the individual as well, since whooping cough tends to be more severe in adults older than 65 than in younger adults. (For more details, see “Advisory Committee Votes for Expanded Pertussis Vaccine Recommendations” from the History of Vaccines blog.)
Although this recommendation was issued last October, some adults older than 65 who wanted to receive a Tdap booster had difficulties obtaining one due to confusion between the ACIP’s recommendation and the FDA’s approved label usage for the vaccine at the time. Neither of the two Tdap vaccines (Sanofi Pasteur’s Adacel and GlaxoSmithKline’s Boostrix) was approved by the FDA for use in adults older than 65. As such, although it was permitted, administering the vaccine in that age group was still considered “off-label” use. (ACIP made their recommendation based on safety data from trials performed after Tdap vaccines were approved for use in adults up to age 65.)
Now, one of the two Tdap vaccines has been approved by the FDA for use in adults aged 65+. Based on clinical trials studying the safety and immunogenicity of the vaccine, GSK’s Boostrix has been approved for use in this age group, and administering it to those aged 65+ will no longer be considered off-label use.
As a reminder, the official ACIP recommendations for adults 65+ are as follows. If all of the checkpoints in this list are met…
- Adult aged 65 or older
- Has not received a prior Tdap vaccination
- Has or anticipates having close contact with an infant younger than 12 months of age
…then the person should receive one dose of the Tdap vaccine to prevent transmission of whooping cough to the infant.
The FDA indication for the vaccine now reads, “Booster immunization against tetanus, diphtheria and pertussis as a single dose in individuals 10 years of age and older.”
Sanofi Pasteur’s Adacel is not yet approved for use in the 65+ age group.
Sources and Additional Reading
FDA Approval Letter – July 8, 2011 – To include immunogenicity and safety data to support the use of Boostrix® in individuals 65 years of age and older. Available at http://www.fda.gov/BiologicsBloodVaccines/Vaccines/ApprovedProducts/ucm262619.htm.
FDA Summary Basis for Regulatory Action (details on approval) – July 8, 2011 – Available at http://www.fda.gov/downloads/BiologicsBloodVaccines/Vaccines/ApprovedProducts/UCM262892.pdf.
Clinical trials providing evidence supporting safety and effectiveness of the vaccine in adults 65+
GSK Study ID BTX111413: Evaluation of GSK Biologicals’ Boostrix® vaccine when compared with DecavacTM in adults aged 65 years or older. Results available at http://download.gsk-clinicalstudyregister.com/files/24200.pdf.
GSK Clinical Study ID BTX106323 : A study to evaluate immunogenicity and safety of Boostrix when co-administered with Fluarix in subjects 19 years of age and older. Results available at http://download.gsk-clinicalstudyregister.com/files/20087.pdf.