Immunogenicity, safety and tolerability of 3 lots of 13-valent pneumococcal conjugate vaccine given with routine pediatric vaccinations in the United States

Immunogenicity and seroefficacy of pneumococcal conjugate vaccines: a systematic review and network meta-analysis

Background

Vaccination of infants with pneumococcal conjugate vaccines is recommended by the World Health Organization. Evidence is mixed regarding the differences in immunogenicity and efficacy of the different pneumococcal vaccines.

Objectives

The primary objective was to compare the immunogenicity of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13. The main secondary objective was to compare the seroefficacy of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13.

Methods

We searched the Cochrane Library, EMBASE, Global Health, MEDLINE, ClinicalTrials.gov and trialsearch.who.int up to July 2022. Studies were eligible if they directly compared either pneumococcal conjugate vaccine-7, pneumococcal conjugate vaccine-10 or pneumococcal conjugate vaccine-13 in randomised trials of children under 2 years of age, and provided immunogenicity data for at least one time point. Individual participant data were requested and aggregate data used otherwise. Outcomes included the geometric mean ratio of serotype-specific immunoglobulin G and the relative risk of seroinfection. Seroinfection was defined for each individual as a rise in antibody between the post-primary vaccination series time point and the booster dose, evidence of presumed subclinical infection. Each trial was analysed to obtain the log of the ratio of geometric means and its standard error. The relative risk of seroinfection ('seroefficacy') was estimated by comparing the proportion of participants with seroinfection between vaccine groups. The log-geometric mean ratios, log-relative risks and their standard errors constituted the input data for evidence synthesis. For serotypes contained in all three vaccines, evidence could be synthesised using a network meta-analysis. For other serotypes, meta-analysis was used. Results from seroefficacy analyses were incorporated into a mathematical model of pneumococcal transmission dynamics to compare the differential impact of pneumococcal conjugate vaccine-10 and pneumococcal conjugate vaccine-13 introduction on invasive pneumococcal disease cases. The model estimated the impact of vaccine introduction over a 25-year time period and an economic evaluation was conducted.

Results

In total, 47 studies were eligible from 38 countries. Twenty-eight and 12 studies with data available were included in immunogenicity and seroefficacy analyses, respectively. Geometric mean ratios comparing pneumococcal conjugate vaccine-13 versus pneumococcal conjugate vaccine-10 favoured pneumococcal conjugate vaccine-13 for serotypes 4, 9V and 23F at 1 month after primary vaccination series, with 1.14- to 1.54-fold significantly higher immunoglobulin G responses with pneumococcal conjugate vaccine-13. Risk of seroinfection prior to the time of booster dose was lower for pneumococcal conjugate vaccine-13 for serotype 4, 6B, 9V, 18C and 23F than for pneumococcal conjugate vaccine-10. Significant heterogeneity and inconsistency were present for most serotypes and for both outcomes. Twofold higher antibody after primary vaccination was associated with a 54% decrease in risk of seroinfection (relative risk 0.46, 95% confidence interval 0.23 to 0.96). In modelled scenarios, pneumococcal conjugate vaccine-13 or pneumococcal conjugate vaccine-10 introduction in 2006 resulted in a reduction in cases that was less rapid for pneumococcal conjugate vaccine-10 than for pneumococcal conjugate vaccine-13. The pneumococcal conjugate vaccine-13 programme was predicted to avoid an additional 2808 (95% confidence interval 2690 to 2925) cases of invasive pneumococcal disease compared with pneumococcal conjugate vaccine-10 introduction between 2006 and 2030.

Limitations

Analyses used data from infant vaccine studies with blood samples taken prior to a booster dose. The impact of extrapolating pre-booster efficacy to post-booster time points is unknown. Network meta-analysis models contained significant heterogeneity which may lead to bias.

Conclusions

Serotype-specific differences were found in immunogenicity and seroefficacy between pneumococcal conjugate vaccine-13 and pneumococcal conjugate vaccine-10. Higher antibody response after vaccination was associated with a lower risk of subsequent infection. These methods can be used to compare the pneumococcal conjugate vaccines and optimise vaccination strategies. For future work, seroefficacy estimates can be determined for other pneumococcal vaccines, which could contribute to licensing or policy decisions for new pneumococcal vaccines.

Study registration

This study is registered as PROSPERO CRD42019124580.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/148/03) and is published in full in Health Technology Assessment; Vol. 28, No. 34. See the NIHR Funding and Awards website for further award information.

Deciphering the Potential of Probiotics in Vaccines

The demand for vaccines, particularly those prepared from non-conventional sources, is rising due to the emergence of drug resistance around the globe. Probiotic-based vaccines are a wise example of such vaccines which represent new horizons in the field of vaccinology in providing an enhanced and diversified immune response. The justification for incorporating probiotics into vaccines lies in the fact that that they hold the capacity to regulate immune function directly or indirectly by influencing the gastrointestinal microbiota and related pathways. Several animal-model-based studies have also highlighted the efficacy of these vaccines. The aim of this review is to collect and summarize the trends in the recent scientific literature regarding the role of probiotics in vaccines and vaccinology, along with their impact on target populations.

Sequential early-life viral infections modulate the microbiota and adaptive immune responses to systemic and mucosal vaccination

Increasing evidence points to the microbial exposome as a critical factor in maturing and shaping the host immune system, thereby influencing responses to immune challenges such as infections or vaccines. To investigate the effect of early-life viral exposures on immune development and vaccine responses, we inoculated mice with six distinct viral pathogens in sequence beginning in the neonatal period, and then evaluated their immune signatures before and after intramuscular or intranasal vaccination against SARS-CoV-2. Sequential viral infection drove profound changes in all aspects of the immune system, including increasing circulating leukocytes, altering innate and adaptive immune cell lineages in tissues, and markedly influencing serum cytokine and total antibody levels. Beyond these immune responses changes, these exposures also modulated the composition of the endogenous intestinal microbiota. Although sequentially-infected mice exhibited increased systemic immune activation and T cell responses after intramuscular and intranasal SARS-CoV-2 immunization, we observed decreased vaccine-induced antibody responses in these animals. These results suggest that early-life viral exposures are sufficient to diminish antibody responses to vaccination in mice, and highlight their potential importance of considering prior microbial exposures when investigating vaccine responses.

Immunogenicity and seroefficacy of 10-valent and 13-valent pneumococcal conjugate vaccines: a systematic review and network meta-analysis of individual participant data

Background

Vaccination of infants with pneumococcal conjugate vaccines (PCV) is recommended by the World Health Organization. Evidence is mixed regarding the differences in immunogenicity and efficacy of the different pneumococcal vaccines.

Methods

In this systematic-review and network meta-analysis, we searched the Cochrane Library, Embase, Global Health, Medline, clinicaltrials.gov and trialsearch.who.int up to February 17, 2023 with no language restrictions. Studies were eligible if they presented data comparing the immunogenicity of either PCV7, PCV10 or PCV13 in head-to-head randomised trials of young children under 2 years of age, and provided immunogenicity data for at least one time point after the primary vaccination series or the booster dose. Publication bias was assessed via Cochrane's Risk Of Bias due to Missing Evidence tool and comparison-adjusted funnel plots with Egger's test. Individual participant level data were requested from publication authors and/or relevant vaccine manufacturers. Outcomes included the geometric mean ratio (GMR) of serotype-specific IgG and the relative risk (RR) of seroinfection. Seroinfection was defined for each individual as a rise in antibody between the post-primary vaccination series time point and the booster dose, evidence of presumed subclinical infection. Seroefficacy was defined as the RR of seroinfection. We also estimated the relationship between the GMR of IgG one month after priming and the RR of seroinfection by the time of the booster dose. The protocol is registered with PROSPERO, ID CRD42019124580.

Findings

47 studies were eligible from 38 countries across six continents. 28 and 12 studies with data available were included in immunogenicity and seroefficacy analyses, respectively. GMRs comparing PCV13 vs PCV10 favoured PCV13 for serotypes 4, 9V, and 23F at 1 month after primary vaccination series, with 1.14- to 1.54- fold significantly higher IgG responses with PCV13. Risk of seroinfection prior to the time of booster dose was lower for PCV13 for serotype 4, 6B, 9V, 18C and 23F than for PCV10. Significant heterogeneity and inconsistency were present for most serotypes and for both outcomes. Two-fold higher antibody after primary vaccination was associated with a 54% decrease in risk of seroinfection (RR 0.46, 95% CI 0.23-0.96).

Interpretation

Serotype-specific differences were found in immunogenicity and seroefficacy between PCV13 and PCV10. Higher antibody response after vaccination was associated with a lower risk of subsequent infection. These findings could be used to compare PCVs and optimise vaccination strategies.

Funding

The NIHR Health Technology Assessment Programme.

Antibiotic Use and Vaccine Antibody Levels

BACKGROUND

The majority of children are prescribed antibiotics in the first 2 years of life while vaccine-induced immunity develops. Researchers have suggested a negative association of antibiotic use with vaccine-induced immunity in adults, but data are lacking in children.

METHODS

From 2006 to 2016, children aged 6 to 24 months were observed in a cohort study. A retrospective, unplanned secondary analysis of the medical record regarding antibiotic prescriptions and vaccine antibody measurements was undertaken concurrently. Antibody measurements relative to diphtheria-tetanus-acellular pertussis (DTaP), inactivated polio (IPV), Haemophilus influenzae type b (Hib), and pneumococcal conjugate (PCV) vaccines were made.

RESULTS

In total, 560 children were compared (342 with and 218 without antibiotic prescriptions). Vaccine-induced antibody levels to several DTaP and PCV antigens were lower (P < .05) in children given antibiotics. A higher frequency of vaccine-induced antibodies below protective levels in children given antibiotics occurred at 9 and 12 months of age (P < .05). Antibiotic courses over time was negatively associated with vaccine-induced antibody levels. For each antibiotic course the child received, prebooster antibody levels to DTaP antigens were reduced by 5.8%, Hib by 6.8%, IPV by 11.3%, and PCV by 10.4% (all P ≤ .05), and postbooster antibody levels to DTaP antigens were reduced by 18.1%, Hib by 21.3%, IPV by 18.9%, and PCV by 12.2% (all P < .05).

CONCLUSIONS

Antibiotic use in children <2 years of age is associated with lower vaccine-induced antibody levels to several vaccines.

Vaccines in Patients with Primary Immune Deficiency

Evaluation of antibodies produced after immunization is central to immune deficiency diagnosis. This includes assessment of responses to routine immunizations as well as to vaccines administered specifically for diagnosis. Here, we present the basic concepts of the humoral immune response and their relevance for vaccine composition and diagnosis of immune deficiency. Current vaccines are discussed, including nonviable protein and glycoprotein vaccines, pure polysaccharide vaccines, polysaccharide-protein conjugate vaccines, and live agent vaccines. Diagnostic and therapeutic applications of vaccine antibody measurement are discussed in depth. Important adverse effects of vaccines are also presented.

Immunogenicity and safety of a novel ten-valent pneumococcal conjugate vaccine in healthy infants in The Gambia: a phase 3, randomised, double-blind, non-inferiority trial

BACKGROUND

An affordable pneumococcal conjugate vaccine (PCV) is needed to ensure sustainable access in low-income and middle-income countries. This trial examined the immunogenicity and safety of a novel ten-valent PCV (SIIPL-PCV) containing serotypes 1, 5, 6A, 6B, 7F, 9V, 14, 19A, 19F, and 23F compared with the pneumococcal polysaccharide protein D-conjugate vaccine (PHiD-CV; Synflorix; GlaxoSmithKline; Brentford, UK).

METHODS

In this single-centre, randomised, double-blind, phase 3, non-inferiority trial in The Gambia, healthy, PCV-naive infants aged 6-8 weeks were enrolled and assigned using permuted block randomisation to receive one of three lots of SIIPL-PCV or to PHiD-CV in a ratio of 2:2:2:3. Parents and all staff assessing study outcomes were masked to group assignment. Vaccines (0·5 mL SIIPL-PCV or 0·5 mL PHiD-CV) were administered at ages 6, 10, and 14 weeks by intramuscular injection. Primary immunogenicity outcomes, measured at age 18 weeks, were serotype-specific IgG geometric mean concentrations (GMCs) and seroresponse rates (IgG ≥ 0·35 μg/mL). Lot-to-lot equivalence (objective 1) was shown if the upper and lower bounds of the two-sided 95% CI around the GMC ratio for each pairwise lot-to-lot comparison was between the 0·5 and 2·0 equivalence margins for all ten serotypes. The immunogenicity of SIIPL-PCV was defined as being non-inferior to that of PHiD-CV (objective 2) if, for at least seven of the ten serotypes in SIIPL-PCV, the lower bound of the 97·5% CI for the GMC ratio was greater than 0·5, or the lower bound of the 97·5% CI for differences in seroresponse rate was greater than -10%. The GMC and seroresponse rates to serotypes 6A and 19A, which are not in PHiD-CV, were compared with those of the serotype in PHiD-CV that had the lowest seroresponse rate. Non-inferiority of the immune responses to antigens in the co-administered Expanded Programme on Immunization (EPI) vaccines (objective 3) was declared if the lower bound of the 95% CI for the difference between SIIPL-PCV and PHiD-CV in seroresponse rates, or GMC ratios for pertussis antigens, was greater than -10% (or 0·5 for pertussis antigens) for all vaccine antigens. Safety data were assessed according to treatment received at the first visit in infants who received at least one dose of study vaccine and for whom at least some post-vaccination safety data were available. The primary immunogenicity analysis was in the per-protocol immunogenicity population, which included infants who received all study vaccines and had immunogenicity measurements after vaccination and no major protocol deviations. This trial is registered at ClinicalTrials.gov (NCT03197376).

FINDINGS

Between June 21, 2017, and Jan 29, 2018, 2250 infants were enrolled and randomly assigned to receive SIIPL-PCV (n=1503; 502 to lot 1, 501 to lot 2, and 500 to lot 3) or PHiD-CV (n=747). 1458 (97·0%) infants assigned to SIIPL-PCV and 724 (96·9%) assigned to PHiD-CV were included in the per-protocol primary immunogenicity analysis. Lot-to-lot equivalence was shown, with the lowest lower bound of the 95% CI for the GMC ratio being 0·52 (for serotype 6B in lot 2 vs lot 3) and the highest upper bound being 1·69 (for serotype 6B in lot 1 vs lot 2). SIIPL-PCV was non-inferior to PHiD-CV in terms of immunogenicity: the lower bound of the 97·5% CI for the GMC ratio was greater than 0·5 (the lowest being 0·67 for serotype 19F) and the lower bound of the 97·5% CI for the difference in seroresponse rate was greater than -10% (the lowest being -2·2% for serotype 6B) for all ten serotypes in SIIPL-PCV. The lowest seroresponse rate after PHiD-CV was to serotype 6B (76·7% [95% CI 73·4-79·7]). This serotype was therefore used for the comparisons with serotype 6A and 19A in SIIPL-PCV. Non-inferiority of immune responses to the EPI vaccines after co-administration with SIIPL-PCV compared with after co-administration with PHiD-CV was shown for all vaccine antigens included in the primary series. The lowest lower bound of the 95% CI for the difference in seroresponse rates was -7·1% for rotavirus antibody and for the GMC ratio for pertussis antigens was 0·62 for anti-pertussis toxoid. 1131 (75·2%) of 1503 infants in the SIIPL-PCV group and 572 (76·6%) of 747 in the PHiD-CV group had at least one unsolicited adverse event. 36 (2·4%) participants in the SIIPL-PCV group and 18 (2·4%) in the PHiD-CV group had a serious adverse event; none were considered related to vaccination. In infants who were selected to have solicited adverse events recorded, injection-site induration after primary vaccinations occurred in 27 (4·9%) of 751 infants who received SIIPL-PCV versus 34 (9·4%) of 364 who received PHiD-CV (p=0·0032). There were no other notable differences in the safety profiles of the two vaccines. One infant in the SIIPL-PCV group and two in the PHiD-CV group died during the study. The deaths were not considered to be related to study vaccination or study participation.

INTERPRETATION

The immunogenicity of SIIPL-PCV was non-inferior to that of PHiD-CV, for which efficacy and effectiveness data against pneumococcal disease are available. The vaccine is safe and can be co-administered with routine EPI vaccines. The data generated in this trial have supported the licensure and pre-qualification of SIIPL-PCV, making the vaccine available for introduction into national immunisation programmes. Generating post-implementation data confirming vaccine impact remains important.

FUNDING

Bill & Melinda Gates Foundation.

Associations between geographic region and immune response variations to pneumococcal conjugate vaccines in clinical trials: A systematic review and meta-analysis

OBJECTIVE

Geographic region can be an important source of variation in the immune response to pneumococcal conjugate vaccines (PCV). The aim of this study was to collate data from available PCV clinical trials in order to characterize the differences in antibody responses in different countries.

METHODS

A systematic review and meta-analysis was conducted to examine the difference in antibody responses after primary series of PCVs in infants, associated with geographic regions, compared with each other and with the different PCVs using random-effects models.

RESULTS

A total of 69 trials were included. Studies conducted in the Western Pacific Region (WPR) showed higher geometric mean concentrations (GMC) compared to studies conducted in Europe. The pooled GMC for serotype 4 after three doses of PCV7 in the WPR was 5.19 μg/ml (95% confidence interval 4.85-5.53 μg/ml), while for studies conducted in Europe this was 2.01 μg/ml (95% confidence interval 1.88-2.14 μg/ml). The IgG GMC ratios among the WPR versus European regions ranged from 1.51 to 2.87 for PCV7, 1.69 to 3.22 for PCV10, and 1.49 to 3.08 for PCV13.

CONCLUSIONS

Studies conducted in the WPR generally showed greater antibody responses than the studies conducted in Europe. Indications of differences among geographic regions highlight the fact that further research is needed to compare the biological factors contributing to immune responses, which may affect vaccination schedules.

Evaluation of a Validated Luminex-Based Multiplex Immunoassay for Measuring Immunoglobulin G Antibodies in Serum to Pneumococcal Capsular Polysaccharides

This article describes the results of a study designed to bridge the World Health Organization (WHO) pneumococcal enzyme-linked immunosorbent assay (ELISA) platform to the validated Luminex-based 13-plex direct immunoassay (dLIA) platform developed by Pfizer, Inc. Both assay platforms quantify serotype-specific serum IgG antibodies (in micrograms per milliliter) against an international reference standard serum. The primary goal of this study was to determine if the dLIA is a suitable replacement for the ELISA to support clinical vaccine studies that include the evaluation of immune responses to serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F. Serum samples were selected from four pivotal 13-valent pneumococcal conjugate vaccine (13vPnC; Prevnar 13) clinical trials on the basis of their serotype-specific IgG concentrations by ELISA. In these studies, subjects were immunized either with 13vPnC or with 7-valent pneumococcal conjugate vaccine (7vPnC; Prevnar). There were 1,528 of 1,574 selected samples with sufficient remaining volume for reanalysis in the dLIA. A comparison of assay results from the dLIA and ELISA platforms showed clear and robust linear quantitative relationships across all 13 serotypes. In addition, lower IgG antibody concentrations in preimmunization samples were measured in the dLIA, thus allowing better differentiation between preimmunization and low-titer postimmunization samples. Overall, the results showed that the established population-level protective threshold IgG concentration, 0.35 µg/ml of serotype-specific serum IgG antibodies, is appropriate for use for data generated using the dLIA platform developed by Pfizer, Inc., for 10 serotypes: serotypes 1, 3, 4, 6A, 7F, 9V, 14, 18C, 19F, and 23F. On the basis of the extensive bridging analyses, however, the use of dLIA cutoff values of 0.23, 0.10, and 0.12 µg/ml is recommended for serotypes 5, 6B, and 19A, respectively. This adjustment will ensure that the consistency of the established population-level protective threshold IgG concentration is maintained when switching from the ELISA to the dLIA platform. The results of this bridging study demonstrate that the 13-plex dLIA platform is a suitable replacement for the WHO reference ELISA platform.IMPORTANCE The pneumococcal enzyme-linked immunosorbent assay (ELISA) measures IgG antibodies in human serum, and it is an important assay that supports licensure of pneumococcal vaccines. The immune correlate of protection, 0.35 µg/ml of IgG antibodies, was determined by the ELISA method. Pfizer has developed a new Luminex-based assay platform to replace the ELISA. These papers describe the important work of (i) validating the Luminex-based assay and (ii) bridging the immune correlate of protection (0.35 µg/ml IgG) to equivalent values reported by the Luminex platform.

Cochlear implant provider awareness of vaccination guidelines

OBJECTIVE

Guidelines for vaccination of cochlear implant (CI) recipients have been promulgated and updated by the Center for Disease Control and Prevention (CDC) to mitigate bacterial meningitis risk. The objective of this study was to survey current CI specialists on: 1) knowledge of current CDC CI recipient immunization recommendations, and 2) impediments to implementation of those guidelines.

METHODS

A survey to assess knowledge of the CI recipient vaccination guidelines was administered to the American Academy of Otolaryngology-Head and Neck surgery (AAO-HNS), the American Cochlear Implant Alliance (ACIA), and the American Neurotology Society (ANS). The members of the AAO-HNS and ACIA were invited to participate in the survey via an e-mail. The members of the ANS were polled during a session of their fall meeting.

RESULTS

A total of 256 individuals participated: 64 from AAO, 59 from ACIA, and 133 from ANS. Participants reported knowledge of the vaccination guidelines as high among all groups and statistically similar. The survey indicated that the participants noted difficulty in obtaining age-group-specific immunizations. Vaccination status was not consistently reported.

CONCLUSION

Cochlear implant providers have high awareness of vaccination guidelines but less detailed knowledge of age-specific recommendations. Obtaining age-specific vaccines is a challenge, as is consistent documentation of vaccination. Future efforts should be focused on improving knowledge of age-specific recommendations, easing access of age-specific vaccines, and improving documentation.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:2145-2152, 2018.

The potential of the microbiota to influence vaccine responses

After clean water, vaccines are the primary public health intervention providing protection against serious infectious diseases. Antigen-specific antibody-mediated responses play a critical role in the protection conferred by vaccination; however these responses are highly variable among individuals. In addition, vaccine immunogenicity is frequently impaired in developing world populations, for reasons that are poorly understood. Although the factors that are associated with interindividual variation in vaccine responses are likely manifold, emerging evidence from mouse models and studies in human populations now suggests that the gut microbiome plays a key role in shaping systemic immune responses to both orally and parenterally administered vaccines. Herein, we review the evidence to date that the microbiota can influence vaccine responses and discuss the potential mechanisms through which these effects may be mediated. In addition, we highlight the gaps in this evidence and suggest future directions for research.

Immunogenicity and Safety of 13-valent Pneumococcal Conjugate Vaccine Compared With 7-valent Pneumococcal Conjugate Vaccine Among Healthy Infants in China

BACKGROUND

Immunogenicity and safety of 13-valent pneumococcal conjugate vaccine (PCV13) were compared with 7-valent pneumococcal conjugate vaccine (PCV7) in Chinese infants.

METHODS

Healthy infants aged 2 months were randomized to a double-blind 3-dose infant series plus 1 toddler dose of PCV7 or PCV13 at 3, 4, 5 and 12 months or open-label PCV13 at 2, 4, 6 and 12 months. Serotype-specific immunoglobulin G (IgG) binding and functionality were measured 1 month after the infant series and after the toddler dose. Local reactions, systemic events and adverse events were assessed postvaccination.

RESULTS

For the 7 common serotypes, serotype-specific binding IgGs elicited by PCV13 were noninferior to PCV7 after the 3-dose infant series; functional antibodies were comparable. For the 6 additional serotypes, PCV13 recipients had significantly higher serotype-specific IgGs and functional antibodies than PCV7 recipients after the infant series. The toddler dose boosted the immune response. Local reactions and systemic events were mild in severity and similar across groups. No new safety signals were identified.

CONCLUSIONS

For the 7 common serotypes, serotype-specific binding IgG after 2 different 3-dose regimens of PCV13 were noninferior to PCV7 responses. PCV13 recipients had significantly higher immune responses to the 6 additional serotypes. PCV13 is expected to provide pneumococcal disease protection comparable to PCV7 for the common serotypes and further protection against disease caused by the 6 additional serotypes. Safety of PCV7 and PCV13 was comparable.

Surveillance of adverse events following the introduction of 13-valent pneumococcal conjugate vaccine in infants, and comparison with adverse events following 7-valent pneumococcal conjugate vaccine, in Victoria, Australia

The 13-valent pneumococcal vaccine (PCV13) replaced the 7-valent vaccine (PCV7) on the Australian National Immunization Program (NIP) in 2011. Post-marketing surveillance of adverse events following immunization (AEFI) is crucial for detecting potential safety signals and maintaining confidence in the NIP. This study describes all AEFI reported to Surveillance of Adverse Events following Vaccination in the Community (SAEFVIC), Melbourne, Australia, following both the primary series of PCV13 (children <7 months) and the catch-up dose (12 months-35 months) in its first year of inclusion on the NIP. AEFI reporting rates per 100,000 doses of vaccine administered were compared for the PCV13 primary series and PCV7 primary series in the previous year. SAEFVIC received 229 reports describing 406 AEFI following PCV13 vaccine in the 12 months post introduction. There was no difference in the total number of AEFI cases reported between the vaccines but 7 AEFI categories were reported at a significantly higher rate following PCV13 compared with PCV7. No difference in reporting rate was observed for serious AEFI (p = 0.25). Post-hoc analysis of a further 12 months of PCV13 data revealed that all 7 AEFI categories that were initially reported at a significantly higher rate following PCV13 compared to PCV7 in the first 12 months post introduction, were no longer significantly increased in the 13-24 month period. The initial high reporting rate for several common AEFI post PCV13 compared to PCV7 may be explained by heightened awareness of the new vaccine. There were no safety signals detected for rare or serious AEFI that would require further investigation at this time.

Impact of 13-valent pneumococcal conjugate vaccine on otitis media bacteriology

OBJECTIVES

To determine the microbiology of otitis media (OM) since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in February 2010.

METHODS

Middle ear effusion from a pediatric Otolaryngology population undergoing pressure equalization tube (PET) placement was obtained and sent for aerobic culture and antibiotic susceptibility testing between August 2012 and April 2013. Vaccination records were obtained and statistical analysis was completed.

RESULTS

During the 8-month period, 236 ears were evaluated, and of those 39 ears were found to have positive cultures. The single nonvaccine Streptococcus pneumoniae (serotype 16) isolate was obtained from a PCV7-only vaccinated patient and was penicillin susceptible. The three most common isolates were Staphylococcus coagulase negative (57%), Haemophilus influenzae (17%), and Moraxella catarrhalis (7%).

CONCLUSIONS

This study is the first to assess the bacteriology of OM in a pediatric population undergoing PET placement in the immediate post-PCV13 era. Our study is limited by sample size; however, the lack of S. pneumoniae cultures indicates that PCV13 has had a significant impact on pneumococcal infections during these initial years following licensure.

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 μg/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 μg/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.