Results
vaccine-type pneumococcal carriageCarriage, NPS
ADVERSE EVENTS
Between March 8, 2017, and July 24, 2018, 2822 participants were screened, 2501 (88·6%) of whom were enrolled and randomly assigned to study groups: 400 to 0 + 1 PCV10, 400 to 0 + 1 PCV13, 402 to 1 + 1 PCV10, 401 to 1 + 1 PCV13, and 898 to control (Trial profileReasons for non-eligibility: 75 had significant medical history, 22 lived or had planned to move outside study area, 15 were outside enrolment age, and 11 had already received their routine 2-month vaccines. Reasons for withdrawal: 184 moved away and were lost to follow-up, 55 voluntarily withdrew, 44 received PCV outside the study, 20 refused study procedure, 3 died, and 12 withdrew for other reasons. Six participants did not have a sample collected at 18 months, a further 66 samples were not analysed for the following reasons: if the swabs were not handled appropriately (two 6-month swabs were inadvertently put in the same tube, one each from the two PCV10 groups), if pneumococcal carriage status could not be determined (n=2, both from the control group at 18 months), or if a serotype could not be determined (n=62). PCV=pneumococcal conjugate vaccine. PCV10=10-valent PCV. PCV13=13-valent PCV. NPS=nasopharyngeal swab.Baseline characteristicsData are n (%) or mean (SD). Percentages might not sum to 100 because of rounding. PCV=pneumococcal conjugate vaccine. PCV10=10-valent PCV. PCV13=13-valent PCV.Missing data: delivery information (birthweight, place of delivery, and type of delivery), one participant (control group); birthweight, one other participant (1 + 1 PCV 10 group); cigarette smoker in house, two participants (control group).A total of 7475 swabs were collected, of which 1290 (17·3%) contained capsular pneumococci (Vaccine efficacy against vaccine-type pneumococcal carriageCarriage prevalence and percent reduction in carriage of vaccine serotypes comparing each vaccine schedule with unvaccinated participants. Lines represent carriage prevalence with shaded bands showing 95% CI. Text above points shows the percent reduction (95% CI) in carriage in the vaccinated group compared with unvaccinated participants. The percent reduction is equivalent to the vaccine efficacy against carriage, calculated as (1 – prevalence ratio) × 100. At 6 months and 12 months (1 + 1 comparisons), data for unvaccinated participants came from the two 0 + 1 groups combined; at 18 and 24 months (all comparisons), data for unvaccinated participants come from the control group. PCV=pneumococcal conjugate vaccine. PCV10=10-valent PCV. PCV13=13-valent PCV.We directly compared the vaccine-type carriage prevalence between the two vaccines (1 + 1 PCV10 We directly compared the vaccine-type carriage prevalence between the two schedules (1 + 1 PCV10 Non-PCV13-type carriage ranged from 6·8% to 8·3% among unvaccinated participants and was generally similar across all groups (We assessed the immunogenicity of the different schedules among a subset of participants after 2-month PCV, before and after 12-month PCV, and at 24 months of age (Serotype-specific GMCs (95% CI) over timeError bars indicate 95% CI. Data for unvaccinated participants comes from the two 0 + 1 groups combined at 3 months (blood sample collected at 2 months in 0 + 1 PCV10 and at 3 months in 0 + 1 PCV13) and 12 months and from the control group at 24 months. GMC=geometric mean concentration of IgG antibody. PCV=pneumococcal conjugate vaccine. PCV10=10-valent PCV. PCV13=13-valent PCV.We evaluated the probable degree of protection between doses afforded by a 1 + 1 schedule of PCV10 or PCV13 in terms of the percentage of participants with protective levels of IgG 4 weeks after the first dose of PCV (at 3 months of age), and of both IgG and functional antibody before the second dose of PCV (at 12 months of age). At 3 months, few unvaccinated participants had IgG of 0·35 μg per mL or more for most serotypes (We compared the immune response to a 12-month dose of PCV10 or PCV13 when given as a booster dose (for the 1 + 1 schedule) or as the first dose (for the 0 + 1 schedule). Both schedules elicited strong responses to the 12-month dose to most vaccine serotypes for both IgG and opsonophagocytic assay (Geometric mean opsonisation index pre-4-weeks and 4-weeks post-12-month dose of PCVData are geometric means (95% CI). PCV=pneumococcal conjugate vaccine. PCV10=10-valent PCV. PCV13=13-valent PCV.Pre-12-month PCV opsonophagocytic assays were only done in one of the two 0 + 1 groups, as these groups have the same vaccination status up to 12 months of age.There were 415 serious adverse events resulting in hospital admissions among 337 participants over the course of the study (