Allison Thompson

Safety and Immunogenicity of a 13-Valent Pneumococcal Conjugate Vaccine Compared to Those of a 7-Valent Pneumococcal Conjugate Vaccine Given as a Three-Dose Series with Routine Vaccines in Healthy Infants and Toddlers

ABSTRACT A 13-valent pneumococcal conjugate vaccine (PCV13) has been developed to improve protection against pneumococcal disease beyond that possible with the licensed 7-valent vaccine (PCV7). This study compared the safety and immunogenicity of PCV13 with those of PCV7 when given as part of the pediatric vaccination schedule recommended in Italy. A total of 606 subjects were randomly assigned to receive either PCV13 or PCV7 at 3, 5, and 11 months of age; all subjects concomitantly received diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated polio-Haemophilus influenzae type B (DTaP-HBV-IPV/Hib) vaccine. Vaccine reactions were monitored. Antibody responses to DTaP-HBV-IPV/Hib antigens, serotype-specific anticapsular polysaccharide IgG responses, and antipneumococcal opsonophagocytic assay (OPA) activity were measured 1 month after the two-dose primary series and 1 month after the toddler dose. Overall, the safety profile of PCV13 was similar to that of PCV7. The response to DTaP-HBV-IPV/Hib antigens was substantially the same with both PCV13 and PCV7. PCV13 elicited antipneumococcal capsular IgG antibodies to all 13 vaccine serotypes, with notable increases in concentrations seen after the toddler dose. Despite a lower immunogenicity for serotypes 6B and 23F after the primary series of PCV13, responses to the seven common serotypes were comparable between the PCV13 and PCV7 groups when measured after the toddler dose. PCV13 also elicited substantial levels of OPA activity against all 13 serotypes following both the infant series and the toddler dose. In conclusion, PCV13 appeared comparable to PCV7 in safety profile and immunogenicity for common serotypes, demonstrated functional OPA responses for all 13 serotypes, and did not interfere with immune responses to concomitantly administered DTaP-HBV-IPV/Hib vaccine.

The 13-valent pneumococcal conjugate vaccine for invasive pneumococcal disease in Alaska native children: results of a clinical trial.

Background: During 1996 to 2000, Alaska Native children aged <5 years from Yukon Kuskokwim Delta (YKD) had invasive pneumococcal disease (IPD) rates 10-fold higher than non-Alaska Native children (547/100,000/yr versus 56/100,000/yr). After 7-valent pneumococcal conjugate vaccine (PCV7) introduction, IPD rates decreased to 148 per 100,000 during 2001 to 2004, increasing to 426 per 100,000 during 2005 to 2007 due to non-vaccine serotype disease. In 2009, we evaluated safety, immunogenicity and impact of 13-valent PCV (PCV13) in YKD children. Methods: In a prelicensure open-label clinical trial, eligible YKD children aged <5 years were offered PCV13 as appropriate for age and prior PCV7 history. PCV13 impact was assessed using existing Alaska-wide IPD surveillance. Serotype-specific anti-pneumococcal IgG levels were measured postinfant series and posttoddler dose in a subset of subjects. Adverse events and serious adverse events were collected in all; local reactions and systemic events were collected in toddlers. All YKD children were offered licensed PCV13 when it became available. Results: Three hundred seventy-two subjects received PCV13 during the clinical trial and 3342 postlicensure (April 2010 to August 2011). Adverse events were typically mild, or generally consistent with common childhood illnesses. IgG levels following PCV13 were similar to other populations. In YKD children aged <5 years, 52 IPD cases (31 PCV13-serotype) occurred during 2005 to 2008 (399.0/100,000/yr) versus 9 (7 PCV13-serotype) during January 2009 to August 2011 (106.7/100,000/yr; P < 0.001). No PCV13-serotype cases occurred among PCV13 recipients (3680 person follow-up years). Conclusions: PCV13-serotype IPD incidence declined significantly after PCV13 introduction. Although non-PCV13-serotype IPD also declined significantly, absence of PCV13-serotype IPD in children who received PCV13 suggests a protective vaccine effect.

Immunogenicity and safety of 13-valent pneumococcal conjugate vaccine in children previously immunized with 7-valent pneumococcal conjugate vaccine.

Background: The 7-valent pneumococcal conjugate vaccine (PCV7) has proven highly effective in preventing diseases caused by Streptococcus pneumoniae; however, in some regions, serotype coverage is limited. A recently licensed 13-valent PCV (PCV13) was developed to provide additional coverage globally. Children previously vaccinated with PCV7 could benefit from supplemental vaccination with PCV13 to provide protection against the 6 additional serotypes in PCV13. This open-label study evaluated the immunogenicity and safety of administering PCV13 to healthy children previously vaccinated with PCV7. Methods: Children between 15 months and 2 years of age (group 1) received 2 doses of PCV13; children between 2 and 5 years (group 2) received 1 dose. Antibodies (immunoglobulin G) against the polysaccharide antigens in PCV13 were measured before vaccination and 1 month after the final dose. Solicited local and systemic adverse events (AEs) were collected for 7 days postvaccination. Unsolicited and serious AEs were collected throughout. Results: A total of 284 subjects (group 1: n = 109; group 2: n = 175) had blood available for testing. Antipneumococcal immunoglobulin G geometric mean fold rises ranged from 2- to 19-fold for the PCV7 serotypes and from approximately 2- to 124-fold for the 6 additional serotypes. Additionally, postvaccination titers in excess of 0.35 &mgr;g/mL, the serologic correlate of immunity against pneumococcus for children, occurred in ≥98% of subjects in both groups for 12 of the 13 serotypes in PCV13. Slightly lower percentage of subjects, 94.5% and 92% of subjects in group 1 and group 2, respectively, had postvaccine titers for serotype 3 exceeding the serologic correlate of immunity. Reactogenicity was typically mild and self-limited, and unsolicited AEs reported were generally consistent with common childhood illnesses. Conclusion: PCV13 was safe and immunogenic when administered to children who had previously received PCV7, and can be used for supplemental vaccination to provide additional protection against the 6 additional serotypes.

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in adults 18-49 years of age, naive to 23-valent pneumococcal polysaccharide vaccine.

BACKGROUND Based on the success of vaccination with pneumococcal conjugate vaccines (PCVs) in children, recent studies have focused on PCVs in adults. Data from a randomized, double-blind study comparing the immunogenicity, tolerability, and safety of the 13-valent PCV (PCV13) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in PPSV23-naive adults 60-64 years of age have been published. The same study also included a cohort of adults aged 18-49 years that received open-label PCV13. The purpose of this cohort was to examine the immunogenicity, safety, and tolerability of PCV13 in adult subjects 18-49 years of age compared with adults 60-64 years of age for whom PCV13 is approved. METHODS Adults naive to PPSV23 were grouped by age into 2 cohorts: 18-49 years (n=899; further stratified by age into 3 subgroups 18-29, 30-39, and 40-49 years) and 60-64 years (n=417). All subjects received 1 dose of PCV13. In both age groups, immunogenicity was assessed by antipneumococcal opsonophagocytic activity (OPA) geometric mean titers (GMTs) and IgG geometric mean concentrations (GMCs) 1 month after vaccination. Safety and tolerability were evaluated. RESULTS In adults aged 18-49 years, OPA GMTs and IgG GMCs were noninferior for all 13 serotypes and statistically significantly higher for all except 1 serotype (OPA GMT) and 5 serotypes (IgG GMCs) compared with adults 60-64 years. Immune responses were highest in the youngest age subgroup (18-29 years). Local reactions and systemic events were more common in adults 18-49 years compared with 60-64 years and were self-limited. CONCLUSION Immune responses to PCV13 are robust in adults ≥18 years of age, with highest responses observed in the youngest subgroup. Based on its safety and immunologic profile, PCV13 may serve an important therapeutic role in younger adults, particularly those with underlying medical conditions who have an increased risk of serious pneumococcal infections.

13-Valent pneumococcal conjugate vaccine in older children and adolescents either previously immunized with or naïve to 7-valent pneumococcal conjugate vaccine.

Background: The 13-valent pneumococcal conjugate vaccine (PCV13) has been demonstrated to be immunogenic and safe for administration to infants and children aged <5 years. PCV13 recently was approved for children and adolescents aged up to 17 years as the vaccine may be of benefit to some in this older age group. Methods: In this open-label study, healthy children aged ≥5 to <10 years (ie, the younger age group) previously vaccinated (≥1 dose) with 7-valent PCV (PCV7) and pneumococcal vaccine-naïve children aged ≥10 to <18 years (ie, the older age group) received 1 dose of PCV13. For the younger group, antipneumococcal immunoglobulin (Ig) G geometric mean concentrations 1 month postvaccination were compared with posttoddler dose (PCV13 or PCV7) levels from a historical control study. Opsonophagocytic activity geometric mean titers 1 month postvaccination for the older group were compared with the younger age group. Safety data were collected. Results: Five hundred and ninety-eight children were enrolled, 299 in each age group. For PCV7 serotypes, IgG geometric mean concentrations in the younger group were 8.23–53.56 &mgr;g/mL, ≥2.5-fold greater than historical posttoddler dose values. For the 6 additional serotypes, IgG geometric mean concentrations in the younger group were 2.38–21.51 &mgr;g/mL, ≥1.2-fold greater than historical posttoddler dose values. Opsonophagocytic activity geometric mean titers were similar in the older and younger age groups, except for serotype 3 which was lower in the older group. Safety was comparable in both groups. Conclusions: PCV13 was immunogenic and safe when administered to older children and adolescents, regardless of prior PCV7 vaccination.

Immune response to 13-valent pneumococcal conjugate vaccine with a reduced dosing schedule

BACKGROUND The 7-valent pneumococcal conjugate vaccine (PCV7) has demonstrated effectiveness against pneumococcal illnesses when administered as 3 infant doses plus a toddler dose (3+1 schedule) or as an abbreviated schedule of 2 infant doses plus a toddler dose (2+1 schedule). The 13-valent pneumococcal conjugate vaccine (PCV13) is approved and World Health Organization-prequalified for administration in a 2+1 schedule when used as part of routine immunization programs. OBJECTIVE To summarize immunologic responses elicited by PCV13 administered in a 2+1 schedule and following 2 doses in a 3+1 schedule. METHODS Studies were double-blind, randomized, active-controlled, multicenter studies except the Mexico study (open-label, single-arm). In 2+1 studies, PCV13 was administered at 2, 4, and 12 (UK) or 3, 5, and 11 (Italy) months. In 3+1 studies (Spain and Mexico), assessment was made postdose 2 of the primary series (2, 4, and 6 months). The primary immunogenicity endpoint was the proportion of participants achieving serotype-specific antipolysaccharide immunoglobulin (Ig)G concentrations ≥ 0.35μg/mL (i.e., responders) 1 month postdose 2. Pneumococcal IgG geometric mean concentrations (GMCs), opsonophagocytic activity (OPA), and concomitant vaccine responses were assessed. RESULTS PCV13 and PCV7 elicited comparable immune responses for the 7 common serotypes after 2 infant doses. The proportion of PCV13 responders postdose 2 was >85% for most of the 7 common and 6 additional serotypes, except common serotypes 6B (27.9-81.4%) and 23F (55.8-77.5%) and additional serotypes 3 (73.8-96.9%) and 6A (79.2-94.4%). Serotypes 6B and 23F elicited lower IgG GMCs postdose 2 compared with other serotypes; all serotypes demonstrated boosting posttoddler dose. All serotypes demonstrated functional activity; >95% of participants achieved OPA levels ≥ 1:8 postdose 2. Concomitant vaccine responses were similar between PCV13 and PCV7 groups. CONCLUSION Immune responses elicited by PCV13 following 2 infant doses support transition from PCV7 to PCV13 in countries using a 2+1 schedule.

Safety of 13-valent pneumococcal conjugate vaccine in infants and children: Meta-analysis of 13 clinical trials in 9 countries

BACKGROUND Meta-analyses enable summarization and interpretation of data across clinical trials. When applied to safety data they allow for detection of rare events. Recently, a 13-valent pneumococcal conjugate vaccine (PCV13) was approved in multiple countries worldwide for routine immunization of infants and young children. This meta-analysis was conducted to identify potentially clinically important rare safety events associated with PCV13. OBJECTIVE To summarize the safety of PCV13 compared with 7-valent pneumococcal conjugate vaccine (PCV7) administered to infants and toddlers. METHODS A meta-analysis was performed of integrated safety data from 13 infant studies (PCV13 n=4729 and PCV7 n=2760) conducted in 9 North American, European, and Asian countries. Local reactions at the vaccine injection site and systemic events were collected for 4-7 days after each dose into electronic diaries. Adverse events (AEs) were collected after each vaccination. RESULTS Overall, rates of local reactions after any dose of the infant series were similar between PCV13 and PCV7 groups: tenderness (46.7% vs 44.8%, respectively); swelling (28.5% vs 26.9%); and redness (36.4% vs 33.9%). After the toddler dose, tenderness was significantly higher among PCV7 subjects than PCV13 subjects (54.4% vs 48.8%; P=0.005). Frequencies of fever (≥38°C) were similar in both groups and mostly mild (≤39°C); incidence of moderate fever (>39°C to ≤40°C) with PCV13 was ≤2.8% after any infant dose and 5.0% after the toddler dose, compared with ≤2.6% and 7.3%, respectively, with PCV7. Fever >40°C was uncommon in both groups. Frequencies of decreased appetite, irritability, and sleep disturbances were similar in both groups. AEs were the types of conditions and symptoms expected in infants and children, and clinically significant differences between vaccine groups were not observed. CONCLUSION PCV13 has a favorable safety profile similar to that of PCV7, a vaccine for which there is >10 years clinical experience.

A phase 3, randomized, double-blind trial comparing the safety and immunogenicity of the 7-valent and 13-valent pneumococcal conjugate vaccines, given with routine pediatric vaccinations, in healthy infants in Brazil ☆

BACKGROUND The inclusion of 7-valent pneumococcal conjugate vaccine (PCV7) into national immunization programs in many countries has significantly decreased the incidence of disease caused by Streptococcus pneumoniae. However, a substantial portion of disease remained and, in some areas, there has been an increase in disease produced by serotypes not included in PCV7. A 13-valent pneumococcal conjugate vaccine (PCV13) was studied in healthy Brazilian infants in a phase 3, double-blind, randomized study. METHODS Infants were randomized to receive either PCV7 or PCV13 at 2, 4, 6, (doses 1-3), and 12 (toddler dose) months of age, along with routine pediatric vaccinations (diphtheria, tetanus, whole-cell pertussis, and Haemophilus influenzae type b vaccine). Pneumococcal anticapsular polysaccharide-binding immunoglobulin G (IgG) responses and antibody responses to pertussis antigens were measured 1 month after both dose 3 of the infant series and the toddler dose. Safety and tolerability were also assessed. RESULTS The proportion of subjects achieving a serotype-specific IgG concentration ≥0.35μg/mL measured 1 month after the infant series was comparable in the PCV13 (≥94.2%) and PCV7 (≥93.0%) groups for the 7 serotypes common to both vaccines. The percentage of responders for the 6 additional serotypes ranged from 87.1 to 100% for PCV13. The percentage of responders varied across the pertussis antigens studied, but was not different in PCV13 and PCV7 recipients. Overall, the safety profile of PCV13 was comparable with that of PCV7. CONCLUSIONS PCV13 was comparable to PCV7 in safety and tolerability, elicited comparable immune responses to the common serotypes, and did not interfere with immune responses to concomitantly administered whole-cell pertussis vaccine. The robust immunogenicity exhibited by PCV13 for the additional serotypes suggests that it could provide significant protection against these serotypes.

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in healthy infants in Japan.

Background: A 13-valent pneumococcal conjugate vaccine (PCV13) containing 6 additional serotypes not included in the 7-valent PCV has been developed to broaden protection against Streptococcus pneumoniae, which is responsible for over 500,000 deaths annually worldwide in children <5 years of age. This study in Japanese infants evaluated the immunogenicity and safety of PCV13 given subcutaneously, the standard route for infant vaccination in Japan. Methods: This phase 3, single-arm, open-label study was conducted at 25 sites. Subjects received PCV13 as a 3-dose infant series and a toddler dose. Parents/legal guardians recorded local reactions and systemic events after each vaccination. The proportion of subjects with serotype-specific antipneumococcal polysaccharide immunoglobulin (Ig)G antibody concentrations ≥0.35 µg/mL was calculated before and 1 month after the infant series and toddler dose. Results: A total of 193 subjects enrolled. The proportion of subjects achieving pneumococcal IgG antibody concentrations ≥0.35 µg/mL was ≥97.2% for all 13 pneumococcal serotypes 1 month after the infant series and 98.9–100% after the toddler dose. IgG geometric mean concentrations were 2.57–14.69 µg/mL after the infant series and 2.06–16.33 µg/mL after the toddler dose. IgG geometric mean concentrations increased from pre- to posttoddler dose by ≥2.8-fold, demonstrating a booster effect. Local reactions and fever were generally mild or moderate in severity. Conclusions: PCV13 was immunogenic for all serotypes and had a favorable safety profile when administered subcutaneously to Japanese infants. PCV13 should offer broader serotype protection than 7-valent PCV in preventing pneumococcal disease in Japanese children.

Immunogenicity and Safety of a 13-Valent Pneumococcal Conjugate Vaccine Given With DTaP Vaccine in Healthy Infants in Japan.

Background: 13-Valent pneumococcal conjugate vaccine (PCV13) provides broader protection against pneumococcal disease than 7-valent pneumococcal conjugate vaccine (PCV7). This study performed in Japan compared the safety and immunogenicity of PCV13 with PCV7. Methods: Healthy Japanese infants received PCV13 and diphtheria, tetanus and acellular pertussis vaccine (DTaP), PCV7 and DTaP or DTaP alone subcutaneously as a 3-dose infant series, with a fourth dose at 12 months of age. Antigen-specific immunoglobulin G (IgG) serum concentrations and opsonophagocytic activity and DTaP antibodies were measured 1 month after doses 3 and 4. Results: After 3 and 4 doses, the proportion of subjects in the PCV13 + DTaP group achieving IgG concentrations ≥0.35 &mgr;g/mL to the 7 serotypes common to PCV13 and PCV7 was noninferior to that of the PCV7 + DTaP group. IgG geometric mean concentrations (GMCs) in the PCV13 + DTaP group were lower than but noninferior to the PCV7 + DTaP group GMCs. For the 6 additional pneumococcal serotypes, the proportion of PCV13 + DTaP group responders achieving IgG concentrations ≥0.35 &mgr;g/mL and IgG GMCs (except serotype 3 after dose 4) was noninferior to the lowest PCV7 + DTaP group pneumococcal response in PCV7 recipients, and responses to the 6 additional antigens were significantly higher. The majority of the subjects achieved prespecified antibody levels to DTaP antigens. GMCs to DTaP antigens were comparable among groups, except filamentous hemagglutinin (numerically higher in the DTaP alone group after dose 4). Conclusions: PCV13 + DTaP was as immunogenic as PCV7 for the 7 common pneumococcal antigens and elicited significantly higher responses to the 6 additional antigens. DTaP responses were comparable across groups. PCV13 given with DTaP was safe and well tolerated.