A Phase 3, Open-Label, Single-Arm Trial Evaluating the Safety, Tolerability, and Immunogenicity of 13-valent Pneumococcal Conjugate Vaccine in Children With Sickle Cell Disease Previously Immunized With 23 Valent pneumococcal polysacchride Vaccine. Read more about A Phase 3, Open-Label, Single-Arm Trial Evaluating the Safety, Tolerability, and Immunogenicity of 13-valent Pneumococcal Conjugate Vaccine in Children With Sickle Cell Disease Previously Immunized With 23 Valent pneumococcal polysacchride Vaccine.