Immunogenicity and safety of a Trivalent Influenza HA vaccine in Indonesian infants and children

Immunogenicity and safety of Quadrivalent Influenza HA vaccine compared with Trivalent Influenza HA vaccine and evaluation of Quadrivalent Influenza HA vaccine batch-to-batch consistency in Indonesian children and adults

One of the newest strategies developed by the Global Influenza Strategy has been to broaden the composition of the current influenza vaccine formulations from trivalent products to quadrivalent products. This study aimed to assess the immunogenicity and safety of Quadrivalent Influenza HA vaccine (QIV) compared with Trivalent Influenza HA vaccine (TIV) and to evaluate three consecutive batches of QIV equivalence in Indonesian children and adults. This was an experimental, randomized, double blind, four arm parallel group bridging study involving unprimed healthy children and adults aged 9-40 years. A total of 540 subjects were enrolled in this study and randomized into four arm groups. Each subject received one dose of TIV or QIV with three different batch codes. Serology tests were performed at baseline and 28 days after vaccination. Hemagglutination inhibition (HI) antibody titers were analyzed for Geometric Mean Titer (GMT), seroprotection, and seroconversion rates. Solicited, unsolicited, and serious adverse events were observed up to 28 days after vaccination. A total of 537 subjects completed the study per protocol and were analyzed for immunogenicity criteria. All randomized subjects were analyzed for safety criteria. The percentage of the subjects with anti-HI titer ≥1:40 28 days after QIV vaccination was 99.5% for A/H1N1; 99.5% for A/H3N2; 93.1% for B/Texas, and 99.0% for B/Phuket. The seroprotection, GMT, and seroconversion rates of QIV were not significantly different from those of TIV for the common vaccine strains (p > 0.01) and were significantly different from those of TIV for the added B/Phuket strains (p < 0.01). Most solicited injection-site and systemic reactions with either vaccine were mild to moderate and resolved within a few days. Antibody response to QIV were equivalence among vaccine batches and comparable between age groups for each of the 4 strains. QIV was immunogenic and well-tolerated and had immunogenicity and safety profiles compared with TIV for all common strains. The immunogenicity of the three batches of QIV was equivalent for the four strains. Trial registration. Clinical Trial registration: NCT03336593.

Association of Single Nucleotide Polymorphisms in LEP, LEPR, and PPARG With Humoral Immune Response to Influenza Vaccine

Background: Although previous studies have proposed leptin plays an important role in energy metabolism as well as in immune response, the effects of leptin-related genes on influenza vaccine-induced immune response remain unexplored. In this study, we aimed to investigate the potential association of leptin gene (LEP), leptin receptor gene (LEPR), and peroxisome proliferator activated receptor gamma gene (PPARG) polymorphisms with humoral immune response to influenza vaccine. Methods: Based on the seroconversion to influenza vaccine, 227 low-responders and 365 responders were selected in this study, and 11 candidate single nucleotide polymorphisms (SNPs) were genotyped using the MassARRAY technology platform. Univariate and multivariate logistic regression analyses were used to explore the association of SNPs in LEP, LEPR, and PPARG with humoral immune response to influenza vaccine. We also conducted a stratified analysis by gender to further clarify this association. The haplotypes analysis was performed using SNPStats. Results: Significant differences were observed in the genotypic distribution of PPARG rs17793951 between the two groups (p = 0.001), and the PPARG rs17793951 AG + GG genotype was associated with a higher risk of low responsiveness to influenza vaccine adjusted for gender and age (additive genetic model: OR = 2.94, 95% CI = 1.67-5.19, dominant genetic model: OR = 2.81, 95% CI = 1.61-4.92). No significant association of other SNPs in LEP and LEPR with immune response to influenza vaccine was found. The stratified analysis found the gender difference in the association of LEPR and PPARG variants with immune response to influenza vaccine. We found that LEPR rs6673591 GA + AA genotype was correlated with low responsiveness to influenza vaccine only in males (OR = 1.96, 95% CI = 1.05-3.67), and PPARG rs17793951 AG + GG genotype was associated with low responsiveness to influenza vaccine in females (OR = 3.28, 95% CI = 1.61-6.67). Compared with the CGGAGGC haplotype composed of LEPR rs1327118, rs7602, rs1137101, rs1938489, rs6673591, rs1137100, and rs13306523, the CAAAAAC haplotype was positively correlated with immune response of influenza vaccine (OR = 0.34, 95% CI = 0.15-0.77). Haplotype TG comprised of PPARG rs796313 and rs17793951 was associated with a 2.85-fold increased risk of low responsiveness to influenza vaccine. Conclusion: Our study identified that PPARG rs17793951 variants were significantly associated with the immune response to influenza vaccine.

Immunogenicity and safety of Quadrivalent Influenza HA vaccine in Indonesian children: An open-labeled, bridging, clinical study

BACKGROUND

Influenza B (Yamagata/Victoria lineage) can cause severe forms of respiratory infection among the pediatric population as well as influenza A strains (H3N2/H1N1). Vaccination against all four strains is required to prevent infection and severe outcome. This study is the first study to assess the immunogenicity of Quadrivalent Influenza HA vaccine (QIV) and ascertain safety among children in Indonesia.

METHODS

This is an open labeled, single arm, bridging clinical study involving unprimed healthy children 6-35 months of age (Group I) and 3-8 years of age (Group II). Subjects on both groups receiving two doses of QIV with a 28 days interval. Serology tests were performed on baseline and 28 days post-vaccination. Hemagglutination inhibition antibody titers were analyzed for Geometric Mean Titer (GMT), seroprotection, and seroconversion rates. Solicited reactions, unsolicited adverse events, and serious adverse events were observed up to 28 days post-vaccination.

RESULTS

Out of 270 subjects enrolled, 269 subjects completed the study. Immunogenicity analysis were evaluated on 254 subjects. Seroprotection rates were ≥85% for all vaccine strains in both groups. Seroconversion of more than 4 folds for all strains occurred in both groups post-vaccination. In Group I, the increase of GMT for A/H1N1, A/H3N2, B/Texas, and B/Phuket was 12.5, 14.5, 8.2, and 6.4 folds, respectively. In Group II the increase of GMT for A/H1N1, A/H3N2, B/Texas, and B/Phuket was 14, 17, 10, and 8 folds, respectively. The majority of local adverse events (AEs) after the first and second immunizations were immediate injection-site pain (10.4% and 12.6%). The majority of systemic AEs after the first and second immunizations were delayed unsolicited AEs (14.8% and 14.9%). No vaccine-related serious adverse events or deaths were reported.

CONCLUSION

The investigational QIV was immunogenic with an acceptable safety profile in children 6 months to 8 years of age.

CLINICAL TRIAL REGISTRATION

NCT03336593.