Estimates of the timing of reductions in genital warts and high grade cervical intraepithelial neoplasia after onset of human papillomavirus (HPV) vaccination in the United States

Cost-effectiveness of nonavalent HPV vaccination among males aged 22 through 26 years in the United States

INTRODUCTION

In the United States, routine human papillomavirus (HPV) vaccination is recommended for females and males at age 11 or 12 years; the series can be started at age 9 years. Vaccination is also recommended for females through age 26 years and males through age 21 years. The objective of this study was to assess the health impact and cost-effectiveness of harmonizing female and male vaccination recommendations by increasing the upper recommended catch-up age of HPV vaccination for males from age 21 to age 26 years.

METHODS

We updated a published model of the health impact and cost-effectiveness of 9-valent human papillomavirus vaccine (9vHPV). We examined the cost-effectiveness of (1) 9vHPV for females aged 12 through 26 years and males aged 12 through 21 years, and (2) an expanded program including males through age 26 years.

RESULTS

Compared to no vaccination, providing 9vHPV for females aged 12 through 26 years and males aged 12 through 21 years cost an estimated $16,600 (in 2016 U.S. dollars) per quality-adjusted life year (QALY) gained. The estimated cost per QALY gained by expanding male vaccination through age 26 years was $228,800 and ranged from $137,900 to $367,300 in multi-way sensitivity analyses.

CONCLUSIONS

The cost-effectiveness ratios we estimated are not so favorable as to make a strong economic case for recommending expanding male vaccination, yet are not so unfavorable as to preclude consideration of expanding male vaccination. The wide range of plausible results we obtained may underestimate the true degree of uncertainty, due to model limitations. For example, the cost per QALY might be less than our lower bound estimate of $137,900 had our model allowed for vaccine protection against re-infection. Models that specifically incorporate men who have sex with men (MSM) are needed to provide a more comprehensive assessment of male HPV vaccination strategies.

The Impact of Varying Numbers of Quadrivalent Human Papillomavirus Vaccine Doses on Anogenital Warts in the United States: A Database Study

OBJECTIVE

The aim of the study was to investigate the effects of 3 or less quadrivalent human papillomavirus (HPV) vaccine doses on anogenital warts in both males and females in the United States.

MATERIALS AND METHODS

We conducted a retrospective database study that included males and females aged 9 to 26 years who received varying numbers of vaccine doses between 2006 and 2015. The primary outcome was the incidence of anogenital warts starting 3 months after the last dose of the HPV vaccine. Proportional hazard regression models were used to examine the association between the number of HPV vaccine doses and the incidence of anogenital warts. The Kaplan-Meier method was used to estimate the proportion of subjects.

RESULTS

A total of 440,532 females and 133,394 males were included in the study. We found a significant 2-way interaction (p < .0001) between the number of doses and age. For the group between 15 and 19 years of age, the hazard ratio of anogenital warts for the 3-dose vaccine was 0.58 (95% CI = 0.49-0.70), whereas it was 0.65 (95% CI = 0.49-0.85) and 0.67 (95% CI = 0.51-0.89) for the 1- and 2-dose groups, respectively.

CONCLUSIONS

Our findings showed that 1, 2, and 3 doses of the quadrivalent HPV vaccine were similarly effective against anogenital warts in 15- to 19-year-old adolescents, irrespective of sex.

The impact and cost-effectiveness of nonavalent HPV vaccination in the United States: Estimates from a simplified transmission model

INTRODUCTION

The objective of this study was to assess the incremental costs and benefits of the 9-valent HPV vaccine (9vHPV) compared with the quadrivalent HPV vaccine (4vHPV). Like 4vHPV, 9vHPV protects against HPV types 6, 11, 16, and 18. 9vHPV also protects against 5 additional HPV types 31, 33, 45, 52, and 58.

METHODS

We adapted a previously published model of the impact and cost-effectiveness of 4vHPV to include the 5 additional HPV types in 9vHPV. The vaccine strategies we examined were (1) 4vHPV for males and females; (2) 9vHPV for females and 4vHPV for males; and (3) 9vHPV for males and females. In the base case, 9vHPV cost $13 more per dose than 4vHPV, based on available vaccine price information.

RESULTS

Providing 9vHPV to females compared with 4vHPV for females (assuming 4vHPV for males in both scenarios) was cost-saving regardless of whether or not cross-protection for 4vHPV was assumed. The cost per quality-adjusted life year (QALY) gained by 9vHPV for both sexes (compared with 4vHPV for both sexes) was < $0 (cost-saving) when assuming no cross-protection for 4vHPV and $8,600 when assuming cross-protection for 4vHPV.

CONCLUSIONS

Compared with a vaccination program of 4vHPV for both sexes, a vaccination program of 9vHPV for both sexes can improve health outcomes and can be cost-saving.

Impact of HPV vaccination on anogenital warts and respiratory papillomatosis

Human papillomavirus (HPV), the most common sexually transmitted infection in the US and worldwide, can cause cancers, anogenital warts (AGW), and recurrent respiratory papillomatosis (RRP) in men, women, and children. Global incidence of AGW ranges from 160-289 cases per 100,000 person-years and peaks in young men and women in the third decade of life. RRP has an estimated incidence of 3 per 1 million person-years in children. Pre-licensure trial efficacy, modeling and time-trend ecological studies have shown a significant short-term impact of 4vHPV vaccine. In girls aged 15-19 years, a previously published meta-analysis indicated that genital warts decreased significantly by 31%; stratified analysis revealed more substantial reductions in populations with high (≥50 %) vs. low (<50 % ) vaccination coverage (61% vs. 14%). Longer-term monitoring will reveal whether this impact continues under 9vHPV programs, and whether current declines in AGW are mirrored by declines in RRP.

Impact and Cost-effectiveness of 3 Doses of 9-Valent Human Papillomavirus (HPV) Vaccine Among US Females Previously Vaccinated With 4-Valent HPV Vaccine

BACKGROUND

We estimated the potential impact and cost-effectiveness of providing 3-doses of nonavalent human papillomavirus (HPV) vaccine (9vHPV) to females aged 13-18 years who had previously completed a series of quadrivalent HPV vaccine (4vHPV), a strategy we refer to as "additional 9vHPV vaccination."

METHODS

We used 2 distinct models: (1) the simplified model, which is among the most basic of the published dynamic HPV models, and (2) the US HPV-ADVISE model, a complex, stochastic, individual-based transmission-dynamic model.

RESULTS

When assuming no 4vHPV cross-protection, the incremental cost per quality-adjusted life-year (QALY) gained by additional 9vHPV vaccination was $146 200 in the simplified model and $108 200 in the US HPV-ADVISE model ($191 800 when assuming 4vHPV cross-protection). In 1-way sensitivity analyses in the scenario of no 4vHPV cross-protection, the simplified model results ranged from $70 300 to $182 000, and the US HPV-ADVISE model results ranged from $97 600 to $118 900.

CONCLUSIONS

The average cost per QALY gained by additional 9vHPV vaccination exceeded $100 000 in both models. However, the results varied considerably in sensitivity and uncertainty analyses. Additional 9vHPV vaccination is likely not as efficient as many other potential HPV vaccination strategies, such as increasing primary 9vHPV vaccine coverage.

Regional variations in HPV vaccination among 9-17 year old adolescent females from the BRFSS, 2008-2010

Human papillomavirus (HPV) vaccine uptake among 18-26 y old women varies by geographic region in the US. However, little is known about regional variations in vaccination among girls who are in the vaccine's targeted age groups. Regional variation in HPV vaccination among female adolescents (9-17 y old) was examined using cross-sectional data from the Behavioral Risk Factor Surveillance System (BRFSS) between 2008 and 2010. Multivariable logistic regression estimated the association of region of residence (10 states included questions about adolescent HPV vaccination) with uptake and completion of the 3-shot HPV vaccine series. Among 7,849 adolescents, 26.9% initiated, and 55.2% of initiators completed the series. Adolescents from Northeast/Midwest/West states were 1.74 (95% CI: 1.45-2.10) times more likely to have initiated HPV vaccination compared to the South/Southwestern states. Among initiators, vaccine series completion did not vary significantly between the South/Southwestern and Northeast/Midwest/West states. Flu vaccination was associated with increased odds of initiation in both regions and completion of the HPV vaccine series in the South/Southwestern states only. Girls 9-10 and 11-12 y old were less likely to have initiated and 11-12 y olds were less likely to have completed the HPV vaccine series compared to 13-17 y olds. The observed regional variations in vaccination could cause rates of cervical cancer to remain higher in the South/Southwest and widen currently observed regional disparities in cervical cancer rates.

Human papillomavirus genotype-specific prevalence across the continuum of cervical neoplasia and cancer

BACKGROUND

The New Mexico HPV Pap Registry was established to measure the impact of cervical cancer prevention strategies in the United States. Before widespread human papillomavirus (HPV) vaccine implementation, we established the baseline prevalence for a broad spectrum of HPV genotypes across the continuum of cervical intraepithelial neoplasia (CIN) and cancer.

METHODS

A population-based sample of 6,272 tissue specimens was tested for 37 HPV genotypes. The number of specimens tested within each diagnostic category was: 541 negative, 1,411 CIN grade 1 (CIN1), 2,226 CIN grade 2 (CIN2), and 2,094 CIN grade 3 (CIN3) or greater. Age-specific HPV prevalence was estimated within categories for HPV genotypes targeted by HPV vaccines.

RESULTS

The combined prevalence of HPV genotypes included in the quadrivalent and nonavalent vaccines increased from 15.3% and 29.3% in CIN1 to 58.4% and 83.7% in CIN3, respectively. Prevalence of HPV types included in both vaccines tended to decrease with increasing age for CIN1, CIN2, CIN3, and squamous cell carcinoma (SCC), most notably for CIN3 and SCC. The six most common HPV types in descending order of prevalence were HPV-16, -31, -52, -58, -33, and -39 for CIN3 and HPV-16, -18, -31, -45, -52, and -33 for invasive cancers.

CONCLUSIONS

Health economic modeling of HPV vaccine impact should consider age-specific differences in HPV prevalence.

IMPACT

Population-based HPV prevalence in CIN is not well described, but is requisite for longitudinal assessment of vaccine impact and to understand the effectiveness and performance of various cervical screening strategies in vaccinated and unvaccinated women.