Reactogenicity of B. pertussis vaccines formulations using aluminum adjuvants in Sprague Dawley rats

Combined vaccines for childhood are a strategy in the prevention of several diseases. These can maximize protection and decrease immunization schedules in children. New candidates are getting closer to being able to meet these needs, but they raise numerous strategic questions related to formulation and regulatory aspects. In addition to being immunogenic and protective must have low reactogenicity when combined with other antigens. Adjuvants are important components in achieving these combinations. Therefore, a reactogenicity study was designed for two B. pertussis formulations containing hydroxide or aluminum phosphate in Sprague Dawley rats. Both formulations dose were administered in 0.2 mL intramuscularly. Clinical evaluations, body weight, water consumption, food, temperature, muscle volume, dermal irritability and pathological studies with special interest at the inoculation site were carried out. Only differences in body temperature and muscle volume were found with a slight increase in values with return to normal. The macroscopic study showed lesions at the site of inoculation, considered characteristics of aluminum adjuvants, such as granulomatous abscesses and the increase in regional lymph nodes near the inoculation site. As conclusion, there are no differences between the formulations of B.pertussis with hydroxide or aluminum phosphate considered low reactogenicity.