Safety and immunogenicity of 15-valent pneumococcal conjugate vaccine (PCV15) in healthy infants

A dose ranging study of 2 different formulations of 15-valent pneumococcal conjugate vaccine (PCV15) in healthy infants

“…However, PCV15-A did not show significant improvement in vaccine performance in comparison to PCV13 for most vaccine serotypes than the initial formulation evaluated in a previous study of PCV15. 15 In contrast, PCV15-B showed significant improvement in vaccine performance for most serotypes in PCV15 in comparison to PCV15-A and the initial formulation evaluated in the study by Greenberg et al 15 Improved immune responses observed for PCV15-B were observed for both IgG GMCs and proportion of subjects achieving threshold value of ≥0.35 µg/mL at both PD3 and PD4. Study results from both studies also confirmed results from previous studies showing that both PCV15-A and PCV15-B induce higher antibodies than PCV13 to serotype 3 for which the effectiveness of the licensed PCV13 appears to be inconsistent, sometimes due the small size of the study cohort [28][29][30][31] ; however, the clinical significance of the observed difference in antibody levels between recipients of PCV15 and PCV13 is unknown without real world evidence of PCV15 effectiveness against disease caused by serotype 3.…”

“…23,24 Although our initial formulation of PCV15 induced both IgG and OPA antibodies to all 15 serotypes included in the vaccine in both adults and infants, levels of serotype-specific antibodies measured following the third dose infant series (1 month PD3) were generally lower to those measured in infants vaccinated with PCV13 for 12 out of 13 shared serotypes between the 2 vaccines. 15 Several hypotheses were suggested for the observed findings including the need to optimize the concentration of PnPs for each vaccine serotype, the amount of adjuvant, and/or parameters in the conjugation process for glycoconjugates. It was very likely that several factors together were responsible for the less than optimal immune responses observed in the study, especially because antibody responses were comparable to PCV13 in toddlers, 25 young adults 18-45 years of age, 26 older adults ≥50 years of age, 27 but not in infants 15 with known immature immune system.…”

“…15 Several hypotheses were suggested for the observed findings including the need to optimize the concentration of PnPs for each vaccine serotype, the amount of adjuvant, and/or parameters in the conjugation process for glycoconjugates. It was very likely that several factors together were responsible for the less than optimal immune responses observed in the study, especially because antibody responses were comparable to PCV13 in toddlers, 25 young adults 18-45 years of age, 26 older adults ≥50 years of age, 27 but not in infants 15 with known immature immune system.…”

“…Study results of the first generation PCV15 in infants, toddlers, and adults showed that PCV15 displayed safety profile comparable to PCV13, but vaccine-induced immune responses were generally lower to PCV13 for most shared serotypes. 15 Subsequently, several modifications were implemented, and 2 new formulations (Formulation A and Formulation B) were developed; dose ranging of PnPs and adjuvant in each PCV15 formulation were evaluated in 2 different Phase 1/2 clinical trials ( Table 1) involving small number of healthy young adults and infants in order to determine the optimal concentrations of PnPs and aluminum adjuvant in PCV15, and ultimately the best PCV15 formulation to evaluate in Phase 2 adult and pediatric clinical development.…”

Safety and immunogenicity of 15-valent pneumococcal conjugate vaccine (PCV-15) compared to PCV-13 in healthy older adults

“…Although these new PCV15 formulations differ in the processes used to manufacture glycoconjugates for some serotypes, the nature of the key vaccine ingredients are generally similar and comparable to an earlier formulation evaluated in children and adults. 40,41 Study results showed that both PCV15-A and PCV15-B displayed tolerability and safety profiles comparable to PCV13 with regard to the nature, frequency, duration, and severity of AEs over the protocol-specified safety follow-up period. With the exception of higher rates of injection site pain/tenderness observed in recipients of both PCV15-A and PCV15-B than in PCV13, no specific trends were observed when comparing reporting rates of other injection-site or systemic AEs across vaccination groups.…”