Immunogenicity and safety of a mixed vaccination schedule with one dose of nonavalent and one dose of bivalent HPV vaccine versus two doses of nonavalent vaccine – A randomized clinical trial

BackgroundLimited data is available on the use of different HPV vaccines in the same subjects. We evaluated the immunogenicity and safety of a mixed vaccination schedule with one dose of nonavalent (9vHPV) and one dose of bivalent vaccine (2vHPV) administered in different order versus two doses of 9vHPV vaccine.Methods371 girls and boys aged 9–10 years were randomized (1:1) to receive (I) two doses of 9vHPV or (II) a mixed schedule of 2vHPV + 9vHPV or 9vHPV + 2vHPV with a 6 month interval. Antibodies to HPV were tested by ELISA in blood samples collected one or six months post-first dose and one month post-second dose.ResultsPost-first dose of 9vHPV 99.4–100% of subjects were seropositive to 9 HPV types included in the vaccine. GMTs varied from 5.0 to 73.6 IU(AU)/ml depending on HPV type. Post-first dose of 2vHPV all subjects were seropositive to HPV16 and 18 (GMTs 16.7 and 11.7 IU/ml, respectively) and 50.0–76.7% were seropositive to 7 types not included in 2vHPV (GMTs varied from 0.3 to 17.5 AU/ml depending on type). Post-second dose all subjects, regardless of the study group, were seropositive to 9 HPV types included in 9vHPV. Anti-HPV16 and 18 GMTs were higher in subjects with the mixed schedule and for the other 7 HPV types higher in subjects who received two doses of 9vHPV vaccine. A higher proportion of subjects who received 2vHPV reported local or systemic adverse events than those who received 9vHPV as the first dose. Post-second dose there were no differences in reported adverse events between the two vaccines.ConclusionsThe results show the mixed HPV vaccination schedules used in this study are immunogenic and have an acceptable safety profile. Although the seroprotective threshold of antibodies remains unknown the 100% seropositivity to all 9 HPV types included in 9vHPV and the increase of GMTs observed in all study groups post-second dose administration are reassuring and suggest protection might be achieved regardless of the schedule used.Clinical Trials Registration: Clinicaltrials.gov NCT02567955.     

Antibody persistence and evidence of immune memory at 5 years following administration of the 9-valent HPV vaccine

BackgroundThe 9-valent HPV (9vHPV) vaccine was developed to prevent infection and disease related to 9 HPV types (HPV6/11/16/18/31/33/45/52/58) which cause approximately 90% of cervical cancers, HPV-related vulvar, vaginal and anal cancers, and genital warts worldwide. In a pivotal efficacy study, the 9vHPV vaccine prevented infection and disease due to the 9 vaccine types. Duration of protection remains to be determined. Vaccines that induce long-term protection are generally characterized by the generation of immune memory. The purpose of this report is to assess the persistence of HPV antibody response and existence of immune memory at 5 years post-vaccination.MethodsA subset of subjects (N = 150) who received 3 doses of 9vHPV vaccine at day 1, month 2 and month 6 in the pivotal efficacy study continued in a study extension and received a fourth dose of 9vHPV vaccine at month 60. Serum HPV antibody levels were measured pre-dose 4 and at 7 and 28 days post-dose 4 by competitive Luminex immunoassay. Adverse events were assessed using a vaccination report card.ResultsHPV antibodies induced following the 3-dose series of 9vHPV vaccine in the base study persisted through month 60 with seropositivity rates ranging from 77.5% to 100%. Geometric mean titers at 1 week and 1 month post-dose 4 were 1.25–4.10 and 1.65–4.88-fold higher, respectively, than levels observed 1 month following the completion of the three-dose primary series. Seropositivity rates were >99% and 100% at 1 week and 1 month post-dose 4, respectively. The fourth dose of 9vHPV vaccine was generally well tolerated.ConclusionsA three-dose regimen of the 9vHPV vaccine induced persistent HPV antibody response through 5 years post-vaccination. Administration of a fourth dose resulted in a strong anamnestic response to all 9 vaccine types. These findings suggest that the efficacy of the 9vHPV vaccine will be long lasting.Clinical Trials.gov Identifier: NCT00543543.     

Vaccine initiation and 3-dose series completion of 4vHPV vaccine among US insured males 2012–2016

ObjectiveThe quadrivalent human papillomavirus vaccine (4vHPV, GARDASIL®⁾, was approved in the US in 2009 for use in males aged 9 to 26 for the prevention of HPV-related genital warts, and in 2010 for the prevention of certain HPV-related anogenital diseases. A regimen was approved in 2016 for those who initiate the vaccine series between the ages of 9 to 14 years. We describe patterns of 4vHPV administration among US males before this modification.MethodsThe study used a US health insurance claims database, and included males, age 9 to 26 years, who initiated 4vHPV between 2012 and 2016. Time from first dose to subsequent doses was estimated. Logistic regression identified factors associated with regimen completion.ResultsAmong 100,786 males who initiated 4vHPV (corresponding to ～ 13% of male birth cohorts), 50,573 (50.2%) and 25,763 (25.6%) received a second and third dose, respectively. Annual administration was common, with 47% of males receiving 3 doses over 3 years (1 dose per year) as compared to 12% receiving the 3-dose series in the recommended 6-month timeframe. Receipt of 4vHPV was 2.2 (range 1.5 to 2.9) times as likely to occur in summer months compared to other times of the year. Individuals aged 18 to 21 years and those living in Western states or rural regions were less likely to complete the 3-dose regimen.ConclusionsThe real-world patterns of 4vHPV vaccination observed, particularly the low uptake and regimen completion, suggest that better strategies are needed for males to improve 4vHPV vaccine use in males.     

Safety and immunogenicity of a 9-valent HPV vaccine in females 12–26 years of age who previously received the quadrivalent HPV vaccine

ObjectivesTo assess the safety and immunogenicity of the investigational 9-valent (6/11/16/18/31/33/45/52/58) HPV (9vHPV) vaccine in prior recipients of a 3-dose regimen of quadrivalent (6/11/16/18) HPV (qHPV) vaccine.MethodsV503-006 was a randomized, double-blinded, safety/tolerability and immunogenicity study of the 9vHPV vaccine in females 12–26 years of age who were previously vaccinated with qHPV vaccine. Subjects were randomized in a 2:1 ratio to receive 3 doses of 9vHPV vaccine (n = 618) or saline placebo (n = 306) at day 1, month 2, and month 6. Systemic, injection-site and serious adverse experiences (AEs) were monitored. Serum samples were collected at day 1, month 2, and month 7. Anti-HPV 6/11/16/18/31/33/45/52/58 titers were measured using the 9-valent HPV competitive Luminex Immunoassay (cLIA).ResultsThe frequency of injection-site AEs (days 1–5 following any vaccination) was higher in the 9vHPV vaccine group than in the placebo group (91.1% and 43.9%, respectively). The frequencies of vaccine-related systemic AEs (days 1–15 following any vaccination) were generally comparable between the 2 groups (30.6% in the 9vHPV vaccine group, and 25.9% in the placebo group). One vaccine-related serious AE was reported in each of the 9vHPV vaccine and placebo groups. Few subjects (9vHPV = 0.5%; placebo = 0%) discontinued due to an AE. At 4 weeks post-dose 3, over 98% of subjects in the 9vHPV vaccine group were seropositive for HPV types 31/33/45/52/58, with marked elevations in cLIA geometric mean titers (GMTs) to these HPV types. Anti-HPV 31/33/45/52/58 GMTs were lower than in subjects administered 9vHPV vaccine who had not previously received qHPV vaccine (based on cross-study analyses); the clinical significance of this difference is unknown.ConclusionsAdministration of a 3-dose regimen of 9vHPV vaccine to adolescent girls and young women 12–26 years of age who are prior qHPV vaccine recipients is highly immunogenic with respect to HPV types 31/33/45/52/58 and generally well tolerated.     

A single dose of quadrivalent human papillomavirus (HPV) vaccine is immunogenic and reduces HPV detection rates in young women in Mongolia,six years after vaccination

BackgroundEmerging observational evidence suggests a single-dose of human papillomavirus (HPV) vaccine may be protective against vaccine-targeted HPV infection and associated cervical dysplasia. We aimed to demonstrate whether a single dose of quadrivalent HPV (4vHPV) vaccine was immunogenic and reduced HPV detection rates in young women in Mongolia. We also assessed knowledge and attitudes regarding HPV and the HPV vaccine.MethodsA retrospective paired cohort study was undertaken to evaluate the effect of a single dose of 4vHPV, given at age 11–17 years in 2012, on HPV detection rates, when compared with unvaccinated women. Real time PCR was performed on self-administered vaginal swabs for HPV detection. An immunological analysis detecting neutralising antibodies (NAb) to high-risk HPV (HRHPV) genotypes 16 and 18 was performed on sera from a subset of 58 participants. Questionnaires evaluated knowledge, attitudes and self-swab acceptability.FindingsA total of 475 women (mean age 20.4 years ± 1.6) were recruited; 118 vaccinated and 357 unvaccinated women. The prevalence of vaccine-targeted HRHPV16 and 18 was reduced by 92% (95%CI 44–99%) in the vaccinated (1·1%) compared with the unvaccinated (15.4%) group. The percentage of non-vaccine HPV genotypes was similar between vaccinated (26.5%) and unvaccinated (26.7%) groups. Approximately 90% and 58% of vaccinated women remained seropositive after six years for HRHPV16 and 18, respectively, with neutralising antibody levels 5- and 2-fold higher than unvaccinated women (p < 0.001).InterpretationOne dose of 4vHPV vaccine reduces vaccine-targeted HPV genotypes, six years following vaccination, with high levels of HR genotype seropositivity among young Mongolian women.     

Caregiver and adolescent factors associated with delayed completion of the three-dose human papillomavirus vaccination series

BackgroundDelayed completion of human papillomavirus vaccination (4vHPV) series is common. We sought to identify factors associated with delay.MethodsThis substudy was part of a large prospective, multi-site study recruiting 9–17 year old girls at the time of their third 4vHPV dose to assess immunogenicity associated with prolonged dosing intervals. At participating sites, parents/legal guardians (caregivers) of all enrolled girls (9–17 years old) and enrolled girls aged 14–17 years were approached for participation. Caregivers completed a questionnaire measuring adolescent and caregiver sociodemographic characteristics, caregiver attitudes and beliefs about on-schedule HPV vaccination and HPV vaccine safety, adolescent’s health behaviors, barriers to accessing health care, provider office vaccination practices and a Rapid Estimate of Adult Literacy in Medicine (REALM). Participating girls completed a separate questionnaire measuring their attitudes and beliefs about on-schedule HPV vaccination and HPV vaccine safety. Delay was defined as receiving the third 4vHPV dose >12 months after the first. Bivariate, multinomial logistic regression and multivariate logistic regression analyses were used to identify factors predicting delayed completion.ResultsQuestionnaires were completed by 482 caregivers and 386 adolescents; 422 caregivers completed a REALM. Delayed 4vHPV dosing occurred in most adolescents (67%). In multivariate analyses, predictors of delayed completion included caregiver demographic factors (self-reported black vs. white race and high school or less education vs. college or more) and an interaction between caregiver’s inability to get an immunization appointment as soon as needed and adolescent’s type of insurance.ConclusionsCaregiver’s race and educational level, accessibility of immunization appointments, and adolescent’s insurance type were found to be related to delays in completion of 4vHPV, but caregiver or adolescent attitudes and beliefs about on-schedule HPV vaccination or HPV vaccine safety were not. Therefore, interventions to improve adherence to recommended vaccination schedules could benefit from a focus on improving access to immunizations.ClinicalTrials.gov (NCT01030562).     

A phase 3, multicenter,randomized, double-blind study to evaluate the interchangeability of V114, a 15-valent pneumococcal conjugate vaccine,and PCV13 with respect to safety,tolerability, and immunogenicity in healthy infants (PNEU-DIRECTION)

BackgroundPneumococcal disease (PD) remains a major health concern globally. In children, pneumococcal conjugate vaccines (PCVs) provide protection against PD from most vaccine serotypes, but non-vaccine serotypes contribute to residual disease. V114 is a 15-valent PCV containing all 13 serotypes in Prevnar 13? (PCV13) and public health important serotypes 22F and 33F. This phase 3 study evaluated safety and immunogenicity of mixed PCV13/V114 regimens using a 3 + 1 dosing schedule when changing from PCV13 to V114 at doses 2, 3, or 4.Methods900 healthy infants were randomized equally to 5 intervention groups. PCVs were administered in a 3-dose infant series at 2, 4, and 6 months of age followed by a toddler dose at 12–15 months along with concomitant routine vaccines. Safety was evaluated as the proportion of participants with adverse events (AEs). Immunoglobulin G (IgG) responses to the 15 serotypes in V114 were measured at 30 days post-dose 3 and 30 days post-dose 4 (PD4).ResultsFrequencies of injection-site and systemic AEs were generally comparable across all intervention groups. At 30 days PD4 (primary endpoint), IgG geometric mean concentrations (GMCs) for the 13 shared serotypes were generally comparable between mixed V114/PCV13 and 4-dose regimens of PCV13 or V114. In mixed regimens at 30 days PD4, a toddler dose of V114 was sufficient to achieve IgG GMCs comparable to a 4-dose regimen of V114 for serotype 22F, while at least one infant dose was needed in addition to the toddler dose to achieve IgG GMCs comparable to a 4-dose regimen of V114 for serotype 33F.ConclusionsV114 was well tolerated with a generally comparable safety profile to PCV13. For 13 shared serotypes, both mixed regimens and the V114 4-dose regimen induced generally comparable antibody responses to 4-dose regimen with PCV13. Study results support interchangeability of V114 with PCV13 in infants.Trial registration: ClinicalTrials.gov: NCT03620162; EudraCT: 2018–001151-12.     

Immunogenicity and safety of the 9-valent HPV vaccine in men

ObjectivesThis study was designed to evaluate the immunogenicity and tolerability of a prophylactic 9-valent HPV (types 6/11/16/18/31/33/45/52/58) VLP (9vHPV) vaccine in young men 16–26 years of age in comparison to young women 16–26 years of age (the population that was used to establish 9vHPV vaccine efficacy). Safety and immunogenicity data from this study will be used to bridge 9vHPV vaccine efficacy findings in 16–26 year old women to 16–26 year old men.MethodsThis study enrolled 1106 heterosexual men (HM) and 1101 women who had not yet received HPV vaccination. In addition, 313 men having sex with men (MSM) were enrolled and were evaluated separately for immunogenicity because previous results showed that antibody responses to quadrivalent HPV (types 6/11/16/18) VLP (qHPV) vaccine were lower in MSM than in HM. All subjects were administered a 3-dose regimen (Day 1, Month 2, Month 6) of 9vHPV vaccine. Serum samples were collected for anti-HPV assays. Safety information was collected for ∼12 months.ResultsThe geometric mean titers (GMTs) for HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58 for HM were non-inferior to those of women at Month 7. For all vaccine HPV types, Month 7 GMTs were numerically lower in MSM than in HM. Over 99.5% of subjects were seropositive at Month 7 for each vaccine HPV type. Administration of 9vHPV vaccine to both 16–26 year old men and women was generally well tolerated.ConclusionsThese results support bridging the efficacy findings with 9vHPV vaccine in young women 16–26 years of age to men 16–26 years of age.     

Maternal and infant outcomes following exposure to quadrivalent human papillomavirus vaccine during pregnancy

IntroductionThe Department of Defense encourages service members ≤26 years of age to receive the human papillomavirus (HPV) vaccine. Although this vaccine is not recommended in pregnancy, inadvertent vaccination may occur. The objective of this study was to assess whether active duty US military women who received the quadrivalent HPV vaccine (4vHPV) during pregnancy were at increased risk for adverse maternal or infant outcomes.MethodsThe study population included active duty US military women aged 17–28 years with at least one pregnancy between 2007 and 2014, and the infants resulting from those pregnancies. Pregnancies, live births, and outcomes were identified using medical codes in administrative medical records. Exposure to 4vHPV during pregnancy was ascertained from personnel immunization records. Multivariable regression models were used to calculate risk estimates and 95% confidence intervals for the maternal outcomes of spontaneous abortion, preeclampsia/eclampsia and preterm labor, and the infant outcomes of preterm birth, birth defects, growth problems in infancy or in utero, and infant sex.ResultsOverall, 90,600 pregnancies and 75,670 singleton infants were identified. Approximately 2% of pregnancies and infants were exposed to 4vHPV during pregnancy. After adjustments, no positive associations were detected between inadvertent exposure to 4vHPV during pregnancy and any adverse pregnancy or infant outcomes.DiscussionOur findings add to an established body of literature demonstrating the safety of 4vHPV when inadvertently administered during pregnancy. Although 4vHPV is no longer administered in the US, its use continues overseas; therefore, safety studies remain important. Furthermore, such studies can provide reassurance to women inadvertently exposed to nonavalent HPV vaccine (9vHPV) in pregnancy, which protects against four of the same antigens as 4vHPV, since safety of 9vHPV has not yet been established in pregnant women.     

Modeling the health and economic implications of adopting a 1-dose 9-valent human papillomavirus vaccination regimen in a high-income country setting: An analysis in the United Kingdom

Although no human papillomavirus (HPV) vaccine is indicated for single-dose administration, some observational evidence suggests that a 1-dose regimen might reduce HPV infection risk to that achieved with 2 doses. This study estimated the potential health and economic outcomes associated with switching from a 2-dose HPV vaccination program for girls and boys aged 13–14 years to an off-label 9-valent (9vHPV), 1-dose regimen, accounting for the uncertainty of the effectiveness and durability of a single dose. A dynamic HPV transmission infection and disease model was adapted to the United Kingdom and included a probabilistic sensitivity analysis using estimated distributions for duration of protection of 1-dose and degree of protection of 1 relative to 2 doses. One-way sensitivity analyses of key inputs were performed. Outcomes included additional cancer and disease cases and the difference in net monetary benefit (NMB). The 1-dose program was predicted to result in 81,738 additional HPV-related cancer cases in males and females over 100 years compared to the 2-dose program, ranging from 36,673 to 134,347 additional cases (2.5% and 97.5% quantiles, respectively), and had a 7.8% probability of being cost-effective at the £20,000/quality-adjusted life years willingness-to-pay (WTP) threshold. In one-way sensitivity analyses, the number of additional cancer cases was sensitive to the median of the duration of protection distribution and coverage rates. The differences in NMBs were sensitive to the median of the duration of protection distribution, dose price and discount rate, but not coverage variations. Across sensitivity analyses, the probability of 1 dose being cost-effective vs 2 doses was < 50% at the standard WTP threshold. Adoption of a 1-dose 9vHPV vaccination program resulted in more vaccine-preventable HPV-related cancer and disease cases in males and females, introduced substantial uncertainty in health and economic outcomes, and had a low probability of being cost-effective compared to the 2-dose program.     

Cost-effectiveness of HPV vaccination for adults through age 45 years in the United States: Estimates from a simplified transmission model

IntroductionThe objective of this study was to assess incremental costs and benefits of a human papillomavirus (HPV) vaccination program expanded to include “mid-adults” (adults aged 27 through 45 years) in the United States.MethodsWe adapted a previously published, dynamic mathematical model of HPV transmission and HPV-associated disease to estimate the incremental costs and benefits of a 9-valent HPV vaccine (9vHPV) program for people aged 12 through 45 years compared to a 9vHPV program for females aged 12 through 26 years and males aged 12 through 21 years.ResultsA 9vHPV program for females aged 12 through 26 years and males aged 12 through 21 years was estimated to cost < $10,000 quality-adjusted life year (QALY) gained, compared to no vaccination. Expanding the 9vHPV program to include mid-adults was estimated to cost $587,600 per additional QALY gained when including adults through age 30 years, and $653,300 per additional QALY gained when including adults through age 45 years. Results were most sensitive to assumptions about HPV incidence among mid-adults, current and historical vaccination coverage, vaccine price, and the impact of HPV diseases on quality of life.ConclusionsMid-adult vaccination is much less cost-effective than the comparison strategy of routine vaccination for all adolescents at ages 11 to 12 years and catch-up vaccination for women through age 26 years and men through age 21 years.     

Cost-effectiveness analysis of quadrivalent and nonavalent human papillomavirus vaccines in Ethiopia

BackgroundIn Ethiopia, cervical cancer is the second most common cancer among women of the reproductive age group. Since 2018, the quadrivalent human papillomavirus (4vHPV) vaccine targeting four HPV types (6/11/16/18) has been introduced in the national immunization program in Ethiopia. Currently, however, a nonavalent HPV (9vHPV) vaccine which provides broader protection against nine HPV types (?6/11/16/18/31/33/45/52/58) is available for global use. Our study, therefore, aims to estimate the cost-effectiveness of 9vHPV vaccine compared to the current HPV vaccination program in Ethiopia.MethodA static Markov cohort model was used to simulate the progression of HPV infection to cervical cancer for a cohort of 12-years-old girls (N = 100,000) in Ethiopia. The model ran up to the age of 100 years, with a cycle length of 1 year. One-way and probabilistic sensitivity analyses were used to explore the robustness of the model and uncertainties around the parameters included in the model. Cost-effectiveness thresholds of one and three times gross domestic product (GDP) per quality-adjusted life-year (QALY) gained were considered.ResultsAt a price of US$ 6.9, the incremental cost-effectiveness ratio (ICER) per QALY gained for the 9vHPV vaccine was US$ 454 compared to the 4vHPV vaccine, which is less than one times GDP per capita of Ethiopia. The ICER was most sensitive to the change in the discount rate of QALYs. Compared to 4vHPV vaccine, for 9vHPV vaccine to remain very cost-effective and cost-effective, its price per dose should not exceed US$ 8.4 and US$ 15, respectively, at a threshold of one and three times GDP per capita.ConclusionCompared to the 4vHPV vaccine, the 9vHPV vaccine is a cost-effective option in Ethiopia, given that its price per dose does not exceed US$15.     

HPV vaccination intent and willingness to pay for 2-,4-, and 9-valent HPV vaccines: A study of adult women aged 27–45 years in China

ObjectiveThis study aims to investigate acceptance and willingness to pay for HPV vaccination among adult women in China.MethodsAn online survey was sent to mothers aged 27–45 years of primary school pupils in the Fujian province, China. Participants completed questions about HPV related knowledge and health beliefs, intention to take the HPV vaccine and the willingness to pay for bivalent vaccine (2vHPV), quadrivalent vaccine (4vHPV), and 9-valent HPV vaccine (9vHPV).ResultsOf a total of 2339 complete responses, 58.3% reported intent to obtain HPV vaccine. Mothers who were younger in age, residing in urban, working in managerial or professional occupations, who knew someone with cervical cancer and who were able to make independent decisions about the HPV vaccine (vs. joint decision with spouse) were more likely to express intent to have HPV vaccination. Perceived barriers, cues to action and self-efficacy were three of the constructs in the health belief model that significantly influenced HPV vaccination intent. A higher proportion of participants expressed willingness to pay for 2vHPV (81.2%) and 4vHPV (75.9%), as compared to 9vHPV (67.7%).ConclusionAdults women expressed moderate intention to receive the HPV vaccine. Intervention to address barriers to uptake of the HPV vaccine among adult women in China is warranted.     

Age at HPV vaccine initiation and completion among US adolescent girls: Trend from 2008 to 2012

ObjectiveTo examine the trend of provider-verified HPV vaccine initiation (≥1 dose) and completion (≥3 doses) among adolescent girls at the Advisory Committee on Immunization Practices (ACIP) recommended age (11–12 years).MethodsWe analyzed National Immunization Survey of Teens 2008–2012 data and examined the trend of provider-verified HPV vaccine initiation and completion among <13 year old girls.ResultsData on age at HPV vaccine initiation and completion were available for 24,466 and 15,972 girls, respectively. The weighted proportion of girls who initiated the vaccine at <13 years of age was 14.1%, 24.1%, 35.9%, 47.7% and 55.9% in 2008, 2009, 2010, 2011 and 2012, respectively (p for trend <.001). The similar trend was also observed for mean age at HPV vaccine initiation and completion (p < .001).ConclusionsAdditional efforts are needed to increase HPV vaccine uptake among adolescent girls as only half of them receive this vaccine at ACIP recommended age.     

Human papillomavirus vaccine series completion in boys before and after recommendation for routine immunization

BackgroundAlthough the incidence of HPV-attributable cancers in males is rapidly increasing, HPV vaccine uptake in males remains poor. While quadrivalent human papillomavirus vaccine (4vHPV) series initiation in males increased following the Advisory Committee Immunization Practices (ACIP) male routine use recommendation, its impact on 4vHPV series completion in males at ACIP-recommended intervals has not been evaluated in large male cohorts. We examined trends and correlates of 4vHPV completion since licensure in males in a large cohort of insured boys before and after the ACIP routine use recommendation.MethodsWe grouped data from electronic medical records of males aged 9–17 years from Kaiser Permanente Southern California health plan who initiated 4vHPV into 3 cohorts by 4vHPV initiation date: licensure and ACIP permissive use: 2009–2010; addition of anal cancer indication: 2010–2011; ACIP routine use: 2011–2013. We estimated adjusted hazard ratios (AHRs) between patient and provider characteristics and vaccination using Marginal Cox proportional hazards models.ResultsOf 80,800 boys initiating 4vHPV, 24.3% completed the series within 12 months with minimal differences across cohorts. Completion decreased with increasing age at initiation (13–17 vs. 11–12 year olds: AHR = 0.85; 95% confidence interval [CI] = 0.80, 0.89) and was greater among patients with a primary care provider (AHR = 1.28, 95%CI = 1.17, 1.41), influenza vaccine recipients (AHR = 1.50, 95% CI = 1.43, 1.57), and Asian/Pacific Islanders (AHR = 1.07, 95% CI = 1.00, 1.15), and lower among non-Hispanic Blacks (AHR = 0.72, 95% CI = 0.65, 0.80) and Hispanics (AHR = 0.86, 95% CI = 0.81, 0.90) compared to non-Hispanic Whites.ConclusionsDespite the ACIP routine use recommendation in males, 4vHPV series completion remained low. 4vHPV initiation at 11–12 years and identification of a provider responsible for the adolescents’ health care may increase 4vHPV series completion. Given the rapidly increasing incidence of HPV-related cancers in males, it is important to identify measures to increase HPV vaccine series completion, particularly among non-Hispanic Black and Hispanic males.     

Human papillomavirus vaccination coverage using two-dose or three-dose schedule criteria

In October 2016, the Advisory Committee on Immunization Practices (ACIP) updated the human papillomavirus (HPV) vaccination recommendation to include a 2-dose schedule for U.S. adolescents initiating the vaccine series before their 15th birthday. We analyzed records for >4 million persons aged 9–17 years receiving any HPV vaccine by the end of each quarter during January 1, 2014–September 30, 2016 from six Immunization Information Systems Sentinel Sites, and reclassified HPV vaccination up-to-date coverage according to the updated recommendations. Compared with HPV vaccination up-to-date coverage by the 3-dose schedule only, including criteria for either a 2-dose or 3-dose schedule increased up-to-date coverage in 11–12, 13–14, and 15–17 year-olds by 4.5–8.5 percentage points. The difference between 3-dose up-to-date coverage and 2- or 3-dose up-to-date coverage was greatest in late 2016. These data provide baseline HPV vaccination coverage using current ACIP recommendations.     

Immunogenicity and safety of two novel human papillomavirus 4- and 9-valent vaccines in Chinese women aged 20–45 years: A randomized,blinded, controlled with Gardasil (type 6/11/16/18), phase III non-inferiority clinical trial

BackgroundHuman papillomavirus (HPV) infections were the main cause of anogenital cancers and warts. HPV 6/11/16/18 vaccines provide protection against the high-risk types of HPV responsible for 70% of cervical cancers and 90% of genital warts. This randomized, blinded, non-inferiority phase III trial was to determine whether immunogenicity and tolerability would be non-inferior among women after receiving two novel 4- and 9-valent HPV vaccines (4vHPV, HPV 6/11/16/18; 9vHPV, HPV 6/11/16/18/31/33/45/52/58) compared with those receiving Gardasil 4 (4-valent).Methods1680 females between 20 and 45 years were randomized in a 2:1:1 ratio to 20–26, 27–35, or 36–45 y groups. Subjects then equally assigned to receive 4vHPV, 9vHPV or Gardasil 4 (control) vaccine at months 0, 2, and 6. End points included non-inferiority of HPV-6/11/16/18 antibodies for 4vHPV versus control, and 9vHPV versus control and safety. The immunogenicity non-inferiority was pre-defined as the lower bound of 95% confidence interval (CI) of seroconversion rate (SCR) difference > ?10% and the lower bound of 95% CI of geometric mean antibody titer (GMT) ratio > 0.5.ResultsAmong the three vaccine groups, more than 99% of the participants seroconverted to all 4 HPV types. The pre-specified statistical non-inferiority criterion for the immunogenicity hypothesis was met: all the lower bounds of 95% CIs on SCR differences exceeded ?10% for each vaccine HPV type and the corresponding lower bounds of 95% CIs for GMT ratios > 0.5. Across vaccination groups, the most common vaccination reaction were injection-site adverse events (AEs), including pain, swelling, and redness. General and serious AEs were similar in the three groups. There were no deaths.ConclusionsThis study demonstrated that the novel 4- and 9-valent HPV vaccination was highly immunogenic and generally well tolerated, both of which were non-inferior to Gardasil 4 in immunogenicity and safety.     

Factors influencing intention to obtain the HPV vaccine and acceptability of 2-, 4- and 9-valent HPV vaccines: A study of undergraduate female health sciences students in Fujian,China

BackgroundLittle research has been conducted on the intention to obtain HPV vaccine now that the vaccine is approved for use in China. Acceptance of the three HPV vaccines, which differ in valency and price, has never been investigated.MethodsAn online cross-sectional survey assessing female undergraduate students’ intention to obtain the HPV vaccine and their acceptability of 2-, 4- and 9-valent HPV vaccines (2vHPV, 4vHPV, and 9vHPV, respectively).ResultsOf a total of 997 complete responses, 55.2% reported intent to obtain the HPV vaccine. Some of the significant factors exerting influence on intent to obtain HPV vaccination were high knowledge score (OR = 1.469, 95% CI:1.087–1.987), perceived high risk of HPV infection (OR = 1.466, 95%CI:1.017–2.114), perception of no serious side effects (OR = 1.562, 95%CI:1.150–2.121), and mass media exposure to HPV vaccination information (OR = 2.196, 95%CI: 1.625–2.966). Socioeconomic status indicators did not significantly influence intent to obtain the HPV vaccine. A higher proportion of respondents were willing to pay for 2vHPV (78.6%) and 4vHPV (68.0%) compared with 9vHPV (49.3%). Socioeconomic status indicators were the strongest correlates of acceptability for all the three vaccines. Exposure to mass media reporting about HPV vaccination is the factor which exerts the most influence on acceptance of 9vHPV after socioeconomic status indicators.ConclusionsIt is important to improve knowledge and health beliefs, and to establish a mass media marketing strategy to promote HPV vaccination in order to enhance HPV vaccine uptake. Undergraduate female students should be provided with detailed information about the different valency vaccine choices to help them make informed decisions about immunization.     

Antibody responses among adolescent females receiving the quadrivalent HPV vaccine series corresponding to standard or non-standard dosing intervals

Quadrivalent human papillomavirus vaccine (HPV4) is recommended as a 3-dose series administered at 0, 1–2, and 6 months. However, this dosing schedule is often not followed leading to longer dosing intervals. We conducted a prospective study to assess antibody titers to HPV4 when dose 2 and/or dose 3 were administered on schedule or delayed. Healthy females (N = 331) aged 9–18 years were enrolled at the time of receipt of HPV4 dose 2 or 3. Participants were classified as belonging to one of four groups depending upon timing of receipt of HPV4: both doses on time; only dose 2 delayed later than 90 days; only dose 3 delayed later than 180 days; or both doses 2 and 3 delayed. Pre- and post-dose 3 blood samples were assayed for HPV antibody titers (types 6, 11, 16, and 18). Post-dose 3 geometric mean titers (GMTs) for all HPV types were not significantly lower for any of the delayed dosing groups when compared to the on time group. When compared to the on time group, the post dose 3 GMTs in the delayed dose 3 group were significantly higher (p < 0.05) for HPV types 6, 11, and 16. Our findings suggest that delays of dose 2 or 3 do not interfere with immune responses after completion of the 3-dose series. These results support current recommendations to not administer additional doses of HPV4 vaccine if dose 2, dose 3, or both doses have been administered late.     

Persistence of immune response following bivalent HPV vaccination: A follow-up study among girls routinely vaccinated with a two-dose schedule

BackgroundIn this cohort study, we examined antibody levels and avidity after a two-dose schedule (0, 6 months) of the bivalent HPV-vaccine in girls routinely vaccinated in the Dutch HPV-vaccination program, up to 2 years following vaccination.MethodsA blood sample at 7, 12 and 24 months after the first dose and questionnaire data were collected (n = 56). HPV type-specific antibody concentrations (lU/ml) against seven types (HPV16/18/31/33/45/52/58) were assessed using a validated virus-like particles (VLP) multiplex immunoassay. Avidity was tested using a modification of this assay.ResultsSeropositivity for vaccine types HPV 16 and 18 was 100% up to month 24, but declined for HPV-types 31/33/45/52/58, although not statistically significant for HPV45. All Geometric Mean Concentrations (GMCs) declined by months 12 and 24, but remained high for HPV16/18. Between month 7 and 12, GMCs declined more for other types. High avidity antibodies were induced up to 24 months for vaccine types (75%, 76–78% and 81–82% at months 7, 12 and 24, respectively), but for other types antibody avidity was 16–29% at month 7, 20–32% at month 12 and 19–32% at month 24.ConclusionsGMCs declined over time for HPV-types 16/18/31/33/45/52/58, but remained high for vaccine-types HPV16/18 up to 24 months of follow-up. Antibody avidity was >75% for vaccine types but <35% for other HPV-types. Further follow-up of this cohort will provide insight into antibody and avidity kinetics over time.