Safety and Immunogenicity of the Quadrivalent HPV Vaccine in Japanese Boys: a Phase 3, Open-Label Study

Sex difference in the immunogenicity of the quadrivalent Human Papilloma Virus vaccine: Systematic review and meta-analysis

BACKGROUND

Immunological differences between males and females in response to viral vaccines are well known. This the first review to examine them for the Human Papilloma Virus.

METHODS

We conducted a systematic review and meta-analysis of the immunogenicity of the Quadrivalent Human Papilloma Virus Vaccine qHPVV. We searched Medline, Embase, and CENTRAL for trials published until September 17, 2019. Inclusion criteria were 3-doses and reporting geometric mean titers (GMTs). We performed random-effects meta-analyses and meta-regression separated by age group and sex.

RESULTS

Our search yielded 1809 unique studies. 334 full texts were screened and data from 18 studies were extracted. Females had higher pooled geometric mean titers than males in all age groups. Log transformed GMTs in male children (<16) years were: against HPV6: 6·62 (95% CI 6·29-6·94; I² = 86·0%), against HPV11: 7·07 (95% CI 6·90-7·23; I² = 63.1%), against HPV16: 8·53 (95% CI 8·28-8·78; I² = 73·0%), and against HPV18 7·21 (95% CI 7·08-7·34; I² = 26·4%). In females: against HPV6 7·10 (95% CI 6·79-7·41; I² = 96·6%), HPV11: 7·32 (95% CI 7·15-7·50; I² = 90·6%), HPV16: 8·71 (95% CI 8·52-8·91; I² = 90·2%), and HPV18 7·35 (95% CI 7·11-7·58; I² = 92·7%). In the meta-regression, the sexual difference was significant for HPV6 (p = 0·022) with a similar tendency for HPV11 (p = 0·066) and HPV18 (p = 0·079). Immunogenicity was significantly higher in children (<16) than in adults (p < 0·001).

CONCLUSION

Females have higher antibody titers against HPV after receiving the qHPVV than do males. The difference is bigger in low-risk HPV strains. Adjusting the doses and schedules for each sex should be explored further.

Post-hoc analysis of injection-site reactions following vaccination with quadrivalent human papillomavirus vaccine in Japanese female clinical trial participants

AIM

The quadrivalent human papillomavirus (4vHPV) vaccine has demonstrated efficacy and immunogenicity and was generally well tolerated in clinical trials conducted in Japan. We report a detailed safety analysis of injection-site reactions in female Japanese 4vHPV clinical trial participants.

METHODS

This post-hoc analysis included data from 2 double-blind, placebo-controlled phase II clinical trials of a 3-dose (Day 1, Month 2, Month 6) regimen of 4vHPV vaccine in Japanese young women aged 18-26 years (N = 1021; NCT00378560) and girls aged 9-17 years (N = 107; NCT00411749). Injection-site and systemic adverse events (AEs) were monitored using vaccination report cards for 15 days after each vaccine dose; serious AEs were reported throughout the trials. Post-hoc analyses of data from these trials were performed to examine details of injection-site AEs, including day of onset, time from onset to resolution, and maximum intensity.

RESULTS

Injection-site AEs were reported by 85.6% of 4vHPV vaccine recipients and 72.4% of placebo recipients, most commonly erythema, pain, pruritus, and swelling (each >5% of 4vHPV vaccine recipients). The majority of injection-site AEs had an onset within 3 days of vaccination and were mild to moderate in intensity; few 4vHPV vaccine recipients reported severe injection-site AEs (2.0% overall). All injection-site AEs resolved, and most (4vHPV: 87.5%; placebo: 92.7%) resolved within 5 days of onset.

CONCLUSIONS

Most injection-site reactions are mild or moderate in intensity and of short duration. The 3-dose regimen of 4vHPV vaccine is well tolerated in Japanese female clinical trial participants based on this post-hoc analysis. These results will further support safety communication between healthcare providers and vaccine recipients regarding the HPV vaccine.

TRIAL REGISTRATION

Clinicaltrials. gov: NCT00378560 and NCT00411749.