Immune response following a two-dose schedule of bivalent HPV vaccination among girls and boys

Background

This longitudinal cohort study describes the kinetics in antibody levels after two doses of the bivalent human papillomavirus (HPV) vaccine in girls (birth cohort 2001) vaccinated in the routine Dutch vaccination program at 12 years of age, up to 7.5 years post-vaccination. Also, the antibody response one month post-vaccination of the first cohort of boys (birth cohort 2012, vaccinated at 10 years of age) eligible for HPV vaccination in the Netherlands is presented.

Method

Blood samples and questionnaire data were collected of girls and boys. HPV type-specific antibody concentrations (LU/mL) against HPV16/18/31/33/45/52/58 were assessed using a validated virus-like particle (VLP) multiplex immunoassay. For girls, antibody decays over time were modelled using the modified power-law decay model and the exponential decay model.

Results

The Geometric Mean Concentrations (GMCs) remained higher for HPV16/18 than for HPV types 31, 33, 45, 52, and 58 among girls up to 7.5 years post-vaccination. The antibody levels of HPV16 and HPV18 reached plateau values of 482 and 159 LU/mL, respectively. Mathematical modelling showed that the half-life values of HPV16/18 were 2.4- to 4.5-fold higher compared with the half-life values of the other HPV types. Among boys (aged 10 years), the GMC for HPV16 was significantly higher than among girls one month post-vaccination (aged 12 years).

Conclusion

The GMCs of all HPV types declined over time, although the GMCs of HPV16/18 remained relatively high up to 7.5 years post-vaccination. The GMCs for HPV16/18 among boys were at least equally high as the GMCs among girls at one month post-vaccination. Further follow-up of the cohort of boys is needed to gain knowledge on long-term immune responses of young boys following bivalent HPV vaccination.

Predictors of the Therapeutic Response to Intralesional Bivalent HPV Vaccine in Wart Immunotherapy

Variable intralesional immunotherapies have recently been proposed as a means of achieving a successful eradication of recurrent and recalcitrant human papillomavirus (HPV)-induced cutaneous and anogenital warts. The bivalent HPV vaccine is one of the newly proposed immunotherapeutic agents. We investigated the role of interleukin-4 (IL-4) and interferon-gamma (IFN-γ) as ex vivo immunologic predictors to estimate the response to the bivalent HPV vaccine as a potential immunotherapy for cutaneous and anogenital warts. Heparinized blood samples were withdrawn from forty patients with multiple recurrent recalcitrant cutaneous and anogenital warts and forty matched healthy control subjects. Whole blood cultures were prepared with and without bivalent HPV vaccine stimulation. Culture supernatants were harvested and stored for IL-4 and IFN-γ measurements using an enzyme-linked immunosorbent assay. A comparative analysis of IL-4 and IFN-γ levels in culture supernatants revealed a non-significant change between the patient and control groups. The bivalent HPV vaccine stimulated cultures exhibited a non-significant reduction in IL-4 levels within both groups. IFN-γ was markedly induced in both groups in response to bivalent HPV vaccine stimulation. The bivalent HPV vaccine can give a sensitive IFN-γ immune response ex vivo, superior to IL-4 and sufficient to predict both the successful eradication of HPV infection and the ultimate clearance of cutaneous and anogenital warts when the bivalent HPV vaccine immunotherapy is applied.

Partial Protective Effect of Bivalent Human Papillomavirus 16/18 Vaccination Against Anogenital Warts in a Large Cohort of Dutch Primary Care Patients

Background

There is ongoing debate about the possible protective effect of the bivalent human papillomavirus (2vHPV) vaccine, targeting oncogenic types HPV-16/18, against anogenital warts (AGWs), commonly attributed to HPV-6/11. We performed a retrospective registry-based open cohort study to assess the effect of 2vHPV vaccination on AGWs.

Methods

We linked general practice (ie, primary care) data from women born between 1993 and 2002, who had been eligible for HPV vaccination in the Netherlands, to the Dutch national immunization registry on an individual level. Women were followed until their first AGW diagnosis or end of follow-up. Adjusted incidence rate ratios (aIRRs) were estimated using Poisson regression with vaccination status as a time-dependent exposure.

Results

We linked data of 96 468 women with a total of 328 019 years observation time and 613 AGW diagnoses (incidence: 1.87/1000 person-years). At the end of follow-up, 61% were 2vHPV vaccinated (≥ 1 dose) of whom 91% were fully vaccinated. The AGW incidence was lower among those with ≥ 1 dose vs 0 doses (aIRR, 0.75 [95% confidence interval {CI}, .64–.88]). The effect of vaccination was stronger after full vaccination (aIRR, 0.72 [95% CI, .61–.86]) and for women who were offered vaccination at 12–13 years of age (aIRR, 0.69 [95% CI, .51–.93]) vs those at 13–16 years of age (aIRR, 0.77 [95% CI, .64–.93]).

Conclusions

This is the largest population-based study so far to examine the effect of 2vHPV vaccination on AGWs, with reliable individual information on AGW diagnoses and vaccination status. The results indicate that 2vHPV vaccination partially protects against AGWs, especially when administered in early adolescence.

A systematic review of immunogenicity, clinical efficacy and safety of human papillomavirus vaccines in people living with the human immunodeficiency virus

The human papillomavirus (HPV) is the most prevalent sexually transmitted infection worldwide. People living with the human immunodeficiency virus (HIV) are at high risk of HPV infection. This systematic review evaluates the immunogenicity, clinical efficacy, and safety of prophylactic HPV vaccines in people living with HIV. We registered the protocol for this review in the International Prospective Register of Systematic Reviews (CRD42018109898) and prepared the review following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). Five randomized trials with 1042 participants are included in this review. One trial with 120 participants compared the bivalent HPV vaccine to placebo, three trials with 830 participants compared the quadrivalent vaccine to placebo, and another trial with 92 participants compared the quadrivalent to the bivalent vaccine. There was low to moderate certainty evidence suggesting that seroconversion was higher among participants in the vaccine arms compared to the placebo arms for both vaccines. In one study with very low certainty evidence, participants who received the bivalent vaccine had higher anti-HPV-18 geometric mean titers (GMTs) compared to those who received the quadrivalent vaccine, despite little difference in anti-HPV-16 GMTs between the two vaccines. There were no differences in the incident and persistent HPV infections in both groups. None of the studies reported data on the incidence of precancerous lesions, or cancer. There were no reports of serious adverse events following vaccination in any of the trials. None of the included studies assessed the effects of HPV vaccines in adolescents living with HIV. Very limited evidence suggests lower immunogenicity of HPV vaccines in HIV positive compared to HIV-negative people. Finally, the long-term effect of the HPV vaccine in the incidence of cervical precancerous lesions and cervical cancer needs to be monitored. There is an urgent need for more high-quality randomized controlled trials that can address these gaps.

Vaccination against HPV and view of new possibilities

OBJECTIVE

Overview of available information on current vaccination options against HPV and possibilities for further development.

DESIGN

Review article.

SETTINGS

Clinic of Gynecology and Obstetrics, University Hospital in Ostrava; Clinic of Gynecology and Obstetrics, General University Hospital in Prague.

METHODS AND RESULTS

Three prophylactic vaccines have been developed against HPV infection and are all now avaliable in Czech Repulbic; nonavalent (Gardasil 9), quadrivalent vaccine (Silgard) and bivalent vaccine (Cervarix). Therapeutic vaccines, designed to induce regression of existing HPV-associated lesions, are in development and not yet clinically available.

CONCLUSION

All three avaliable prophylactic vaccines show high efficacy in prevention of vaccine-specific HPV-type infection. The highest degree of protection is achieved in the population of HPV-naive women.