The Food and Drug Administration (FDA) approved a new vaccine for a single booster immunization against pertussis (whooping cough), in combination with tetanus and diphtheria, for adolescents and adults 11-64 years of age. The vaccine will be marketed as Adacel by Aventis Pasteur Limited located in Toronto, Canada. Adacel is the first vaccine approved as a pertussis booster for adults. Vaccines for prevention of tetanus and diphtheria (Td vaccine) in adolescents and adults have been available for many years, a FDA release said.

Adacel is a Tetanus Toxoid (T), Reduced Diphtheria Toxoid (d) and Acellular Pertussis Vaccine (ap), Adsorbed. Adacel contains the same components as Daptacel, a DTaP vaccine indicated for infants and children manufactured by Aventis Pasteur Limited, but the diphtheria toxoid and one of the pertussis components are in reduced quantities.

Recently, FDA approved a similar vaccine called Boostrix, manufactured by GlaxoSmithKline, for use in adolescents 10-18 years of age.

Pertussis is a highly communicable and potentially serious illness in adolescents and adults, and can cause prolonged cough and missed days at school and work. In young infants, pertussis is more frequently severe and can be fatal, particularly in those too young to be fully vaccinated. Since 1980, the rates of reported pertussis cases have been increasing in adolescents and adults, as well as in young infants. Adolescents and adults have been implicated as the source of pertussis infection for susceptible young infants, and other family members.

The ability of Adacel to protect against pertussis was assessed by comparing the antibody responses of adolescents and adults who received it with the antibody responses of infants who had received Daptacel in a clinical trial. The antibody responses of the adolescents and adults who received a single dose of Adacel were at least as good as those observed in the infants following three doses of Daptacel. For diphtheria and tetanus, the antibody responses following Adacel were comparable to those following immunization with a U.S. licensed Td vaccine.

In clinical trials, the safety of Adacel was compared to a US licensed Td vaccine. Among adolescent recipients of Adacel, injection site pain and low grade fever were observed more frequently than among those who received Td vaccine. Rates of adverse reactions were similar in adults receiving Adacel vaccine or receiving Td vaccine.