RATIONALE: New vaccines are urgently needed to protect the vulnerable from @entity2028 . Clinical trials of @entity55 vaccines are slow and costly, requiring tens of thousands of @entity1 . Studies of pneumococcal vaccine efficacy against colonization have been proposed as a novel method to down-select between vaccine candidates. OBJECTIVES: Using our safe and reproducible experimental @entity1 pneumococcal colonization model, we aimed to determine the effect of 13-valent pneumococcal conjugate vaccine ( @entity1485 ) on colonization. METHODS: A total of 100 healthy @entity1 aged 18-50 years were recruited into this double-blind randomized placebo-controlled trial. They were randomly assigned to @entity1485 (n   =   49) or @entity99 (control, n   =   50) vaccination and inoculated with 80,000 CFU/100  l of @entity328 (6B) per naris. MEASUREMENTS AND MAIN RESULTS: @entity1 were followed up for 21 days to determine pneumococcal colonization by culture of nasal wash. The @entity1485 group had a significantly reduced rate of 6B colonization (10% [5 of 48]) compared with control subjects (48% [23 of 48]) (risk ratio, 0.22; confidence interval, 0.09-0.52; P   <   0.001). Density of colonization was reduced in the @entity1485 group compared with the control group following inoculation. The area under the curve (density vs. day) was significantly reduced in the @entity1485 compared with control group (geometric mean, 259 vs. 11,183; P   =   0.017). CONCLUSIONS: @entity1485 reduced pneumococcal colonization rate, density, and duration in healthy adults. The experimental @entity1 pneumococcal colonization model is a safe, cost-effective, and efficient method to determine the protective efficacy of new vaccines on pneumococcal colonization; @entity1485 provides a gold standard against which to test these novel vaccines. Clinical trial registered with ISRCTN: 45340436.

First XXXX Challenge Testing of a Pneumococcal Vaccine. Double-Blind Randomized Controlled Trial.

@entity1 :: ('9606', 'Species') :: ['participants', 'human', 'patients', 'Participants'] @entity55 :: ('MESH:D011014', 'Disease') :: ['pneumonia'] @entity1485 :: ('158372', 'Species') :: ['PCV'] @entity2028 :: ('MESH:D018410', 'Disease') :: ['bacterial pneumonia'] @entity99 :: ('MESH:D056486', 'Disease') :: ['hepatitis A'] @entity328 :: ('1313', 'Species') :: ['Streptococcus pneumoniae']
@entity1 :: (9606,Species) :: ['Human']
