Safety, Tolerability, and Efficacy Study of Prophylactic S. Pneumoniae Vaccine Following Challenge With S. Pneumoniae

This is a randomized, double-blind, placebo-controlled study. Eligible subjects will be randomized in a 1:1 ratio to receive GEN-004 with adjuvant or placebo. Each subject will receive up to 3 doses at 4 week intervals. Following the third dose, subjects will be inoculated intranasally with S. pneumoniae serotype 6B. Nasal washes to identify S. pneumoniae colonization will be obtained pre-inoculation, and then 2, 7 and 14 days after inoculation. Subjects will also be monitored for safety and tolerability throughout the dosing period, and then for 12 months after their last dose. The purpose of this study is to evaluate the effectiveness of GEN-004 in reducing colonization rates and magnitude of colonization following the S. pneumoniae challenge.