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SYNFLORIX Tolerabilty and Safety profile

Demonstrated safety profile* 1

  • No increase in the incidence or severity of the adverse reactions was seen with subsequent doses of the primary vaccination series
  • Most common adverse reactions observed after primary vaccination were redness at the injection site (41%) and irritability (55%) and, following booster vaccination, pain at the injection site (51%) and irritability (53%)
  • Most of these reactions were of mild-to-moderate severity and were not long lasting

* Safety assessment based on clinical trials involving the administration of approximately 64,000 doses of SYNFLORIX to approximately 22,500 healthy children and 137 healthy premature infants as primary vaccination. Furthermore, approximately 19,500 healthy children and 116 premature infants received a booster dose of SYNFLORIX in the second year of life. Safety was also assessed in 400 children from 2 to 5 years of age. In all trials, SYNFLORIX was administered concurrently with the recommended childhood vaccines.


  1. Synflorix Product Monograph. GlaxoSmithKline Inc. August 31, 2018.