according to Heta Nieminen, MD, of the National Institute for Health and Welfare in Tampere, Finland, and associates.
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For the study, published in Vaccine, the investigators conducted a post hoc analysis of the phase III/IV, cluster-randomized, double-blind FinIP trial, in which more than 30,000 infants received the PHiD-CV10 vaccine or a placebo. Patients were aged less than 7 months when they received their first vaccination, and received two or three primary doses, plus a booster shot after the age of 11 months (Vaccine. 2019 May 20. doi: 10.1016/j.vaccine.2019.05.033).
In term infants, vaccine effectiveness was similar in boys and girls; while the vaccine worked marginally better in girls, the difference was not significant. Infants who received the 2 + 1 schedule had vaccine effectiveness similar to that of those who received the 3 + 1 schedule. In a smaller subanalysis of 1,519 preterm infants, outcomes of pneumonia were more common, but the vaccine seemed to confer protection, although the sample size was not large enough for statistical significance to be reached.
“The point estimates of vaccine effectiveness suggest protection in both sexes, and also among the preterm and low-birth-weight infants. ... There were no significant differences between the 2 + 1 and 3 + 1 schedules in any of the subgroups analyzed. Based on this study, the 2 + 1 or “Nordic” schedule is sufficient also for the risk groups such as the preterm or low-birth-weight infants,” the investigators concluded.
Five study authors are employees of the National Institute for Health and Welfare, which received funding for the study from GlaxoSmithKline. Four coauthors are employees of GlaxoSmithKline; three of them own shares in the company.