Design of a large outcome trial for a multivalent human papillomavirus L1 virus-like particle vaccine

Long-term effectiveness of the nine-valent human papillomavirus vaccine in Scandinavian women: interim analysis after 8 years of follow-up

A long-term follow-up (LTFU) of the nine-valent human papillomavirus (9vHPV) vaccine efficacy study in young women aged 16–26 years was initiated to evaluate if vaccine effectiveness for up to 14 years post-vaccination will remain above 90%. Vaccine effectiveness is measured as percent reduction in the incidence of HPV16/18/31/33/45/52/58-related high-grade cervical dysplasia in the LTFU cohort relative to expected incidence in a similar unvaccinated cohort. We report an interim analysis 8 years post-vaccination. Overall, 2029 participants from Denmark, Norway, and Sweden who received the 9vHPV vaccine during the clinical efficacy study continued into the LTFU study. National health registries were used to identify screening attendance and cervical pre-cancer/cancer diagnoses. Tissue samples were retrieved for HPV testing by PCR and pathology diagnosis adjudication. A control chart method was used to detect signals indicative of vaccine effectiveness waning below 90%. No new cases of HPV16/18/31/33/45/52/58-related high-grade cervical dysplasia were observed during the LTFU study period over 4084.2 person-years’ follow-up (per-protocol effectiveness population; n = 1448). Thus, there were no signals indicative of vaccine effectiveness waning below 90%. These observations show that the 9vHPV vaccine provides continued statistically significant protection through at least 6 years, with indications of continued effectiveness through 8 years.

Trial registration

Clinicaltrials.gov: NCT00543543, NCT02653118.

Long-term immunogenicity, effectiveness, and safety of nine-valent human papillomavirus vaccine in girls and boys 9 to 15 years of age: Interim analysis after 8 years of follow-up

BACKGROUND

The nine-valent human papillomavirus (9vHPV) vaccine protects against infection and disease related to HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. The pivotal 36-month Phase III immunogenicity study of 9vHPV vaccine in 9- to 15-year-old girls and boys was extended to assess long-term immunogenicity and effectiveness through approximately 10 years after vaccination. We describe results of an interim analysis based on approximately 8 years of follow-up after vaccination.

METHODS

Participants aged 9-15 years who received three doses of 9vHPV vaccine (at day 1, month 2, and month 6) in the base study and consented to follow-up were enrolled in the long-term follow-up study extension (N = 1272 [females, n = 971; males, n = 301]). Serum was collected at months 66 and 90 to assess antibody responses. For effectiveness analysis, genital swabs were collected (to assess HPV DNA by polymerase chain reaction [PCR]) and external genital examination was conducted (to detect external genital lesions) every 6 months starting when the participant reached 16 years of age. Cervical cytology tests were conducted annually when female participants reached 21 years of age; participants with cytological abnormalities were triaged to colposcopy based on a protocol-specified algorithm. External genital and cervical biopsies of abnormal lesions were performed, and histological diagnoses were adjudicated by a pathology panel. Specimens were tested by PCR to detect HPV DNA.

RESULTS

Geometric mean titers for each 9vHPV vaccine HPV type peaked around month 7 and gradually decreased through month 90. Seropositivity rates remained >90% through month 90 for each of the 9vHPV vaccine types by HPV immunoglobulin Luminex Immunoassay. No cases of HPV6/11/16/18/31/33/45/52/58-related high-grade intraepithelial neoplasia or genital warts were observed in the per-protocol population (n = 1107) based on a maximum follow-up of 8.2 years (median 7.6 years) post-Dose 3. Incidence rates of HPV6/11/16/18/31/33/45/52/58-related 6-month persistent infection in females and males were 49.2 and 37.3 per 10,000 person-years, respectively, which were within ranges expected in vaccinated cohorts. There were no vaccine-related SAEs or deaths during the period covered by this interim analysis.

CONCLUSIONS

The 9vHPV vaccine provided sustained immunogenicity and durable effectiveness through approximately 7 and 8 years, respectively, following vaccination of girls and boys aged 9-15 years.

Comparison of different human papillomavirus (HPV) vaccine types and dose schedules for prevention of HPV-related disease in females and males

BACKGROUND

Uptake of human papillomavirus (HPV) vaccine remains low in many countries, although the bivalent and quadrivalent HPV vaccines given as a three-dose schedule are effective in the prevention of precancerous lesions of the cervix in women. Simpler immunisation schedules, such as those with fewer doses, might reduce barriers to vaccination, as may programmes that include males.

OBJECTIVES

To evaluate the efficacy, immunogenicity, and harms of different dose schedules and different types of HPV vaccines in females and males.

SEARCH METHODS

We conducted electronic searches on 27 September 2018 in Ovid MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL) (in the Cochrane Library), and Ovid Embase. We also searched the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov (both 27 September 2018), vaccine manufacturer websites, and checked reference lists from an index of HPV studies and other relevant systematic reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with no language restriction. We considered studies if they enrolled HIV-negative males or females aged 9 to 26 years, or HIV-positive males or females of any age.

DATA COLLECTION AND ANALYSIS

We used methods recommended by Cochrane. We use the term 'control' to refer to comparator products containing an adjuvant or active vaccine and 'placebo' to refer to products that contain no adjuvant or active vaccine. Most primary outcomes in this review were clinical outcomes. However, for comparisons comparing dose schedules, the included RCTs were designed to measure antibody responses (i.e. immunogenicity) as the primary outcome, rather than clinical outcomes, since it is unethical to collect cervical samples from girls under 16 years of age. We analysed immunogenicity outcomes (i.e. geometric mean titres) with ratios of means, clinical outcomes (e.g. cancer and intraepithelial neoplasia) with risk ratios or rate ratios and, for serious adverse events and deaths, we calculated odds ratios. We rated the certainty of evidence with GRADE.

MAIN RESULTS

We included 20 RCTs with 31,940 participants. The length of follow-up in the included studies ranged from seven months to five years. Two doses versus three doses of HPV vaccine in 9- to 15-year-old females Antibody responses after two-dose and three-dose HPV vaccine schedules were similar after up to five years of follow-up (4 RCTs, moderate- to high-certainty evidence). No RCTs collected clinical outcome data. Evidence about serious adverse events in studies comparing dose schedules was of very low-certainty owing to imprecision and indirectness (three doses 35/1159; two doses 36/1158; 4 RCTs). One death was reported in the three-dose group (1/898) and none in the two-dose group (0/899) (low-certainty evidence). Interval between doses of HPV vaccine in 9- to 14-year-old females and males Antibody responses were stronger with a longer interval (6 or 12 months) between the first two doses of HPV vaccine than a shorter interval (2 or 6 months) at up to three years of follow-up (4 RCTs, moderate- to high-certainty evidence). No RCTs collected data about clinical outcomes. Evidence about serious adverse events in studies comparing intervals was of very low-certainty, owing to imprecision and indirectness. No deaths were reported in any of the studies (0/1898, 3 RCTs, low-certainty evidence). HPV vaccination of 10- to 26-year-old males In one RCT there was moderate-certainty evidence that quadrivalent HPV vaccine, compared with control, reduced the incidence of external genital lesions (control 36 per 3081 person-years; quadrivalent 6 per 3173 person-years; rate ratio 0.16, 95% CI 0.07 to 0.38; 6254 person-years) and anogenital warts (control 28 per 2814 person-years; quadrivalent 3 per 2831 person-years; rate ratio 0.11, 95% CI 0.03 to 0.38; 5645 person-years). The quadrivalent vaccine resulted in more injection-site adverse events, such as pain or redness, than control (537 versus 601 per 1000; risk ratio (RR) 1.12, 95% CI 1.06 to 1.18, 3895 participants, high-certainty evidence). There was very low-certainty evidence from two RCTs about serious adverse events with quadrivalent vaccine (control 12/2588; quadrivalent 8/2574), and about deaths (control 11/2591; quadrivalent 3/2582), owing to imprecision and indirectness. Nonavalent versus quadrivalent vaccine in 9- to 26-year-old females and males Three RCTs were included; one in females aged 9- to 15-years (n = 600), one in females aged 16- to 26-years (n = 14,215), and one in males aged 16- to 26-years (n = 500). The RCT in 16- to 26-year-old females reported clinical outcomes. There was little to no difference in the incidence of the combined outcome of high-grade cervical epithelial neoplasia, adenocarcinoma in situ, or cervical cancer between the HPV vaccines (quadrivalent 325/6882, nonavalent 326/6871; OR 1.00, 95% CI 0.85 to 1.16; 13,753 participants; high-certainty evidence). The other two RCTs did not collect data about clinical outcomes. There were slightly more local adverse events with the nonavalent vaccine (905 per 1000) than the quadrivalent vaccine (846 per 1000) (RR 1.07, 95% CI 1.05 to 1.08; 3 RCTs, 15,863 participants; high-certainty evidence). Comparative evidence about serious adverse events in the three RCTs (nonavalent 243/8234, quadrivalent 192/7629; OR 0.60, 95% CI 0.14 to 2.61) was of low certainty, owing to imprecision and indirectness. HPV vaccination for people living with HIV Seven RCTs reported on HPV vaccines in people with HIV, with two small trials that collected data about clinical outcomes. Antibody responses were higher following vaccination with either bivalent or quadrivalent HPV vaccine than with control, and these responses could be demonstrated to have been maintained for up to 24 months in children living with HIV (low-certainty evidence). The evidence about clinical outcomes and harms for HPV vaccines in people with HIV is very uncertain (low- to very low-certainty evidence), owing to imprecision and indirectness.

AUTHORS' CONCLUSIONS

The immunogenicity of two-dose and three-dose HPV vaccine schedules, measured using antibody responses in young females, is comparable. The quadrivalent vaccine probably reduces external genital lesions and anogenital warts in males compared with control. The nonavalent and quadrivalent vaccines offer similar protection against a combined outcome of cervical, vaginal, and vulval precancer lesions or cancer. In people living with HIV, both the bivalent and quadrivalent HPV vaccines result in high antibody responses. For all comparisons of alternative HPV vaccine schedules, the certainty of the body of evidence about serious adverse events reported during the study periods was low or very low, either because the number of events was low, or the evidence was indirect, or both. Post-marketing surveillance is needed to continue monitoring harms that might be associated with HPV vaccines in the population, and this evidence will be incorporated in future updates of this review. Long-term observational studies are needed to determine the effectiveness of reduced-dose schedules against HPV-related cancer endpoints, and whether adopting these schedules improves vaccine coverage rates.

Efficacy, Immunogenicity, and Safety of a 9-Valent Human Papillomavirus Vaccine: Subgroup Analysis of Participants From Asian Countries

Background

A 9-valent human papillomavirus-6/11/16/18/31/33/45/52/58 (9vHPV) vaccine extends coverage to 5 next most common oncogenic types (31/33/45/52/58) in cervical cancer versus quadrivalent HPV (qHPV) vaccine. We describe efficacy, immunogenicity, and safety in Asian participants (India, Hong Kong, South Korea, Japan, Taiwan, and Thailand) from 2 international studies: a randomized, double-blinded, qHPV vaccine-controlled efficacy study (young women aged 16–26 years; NCT00543543; Study 001); and an immunogenicity study (girls and boys aged 9–15 years; NCT00943722; Study 002).

Methods

Participants (N = 2519) were vaccinated at day 1 and months 2 and 6. Gynecological samples (Study 001 only) and serum were collected for HPV DNA and antibody assessments, respectively. Injection-site and systemic adverse events (AEs) were monitored. Data were analyzed by country and vaccination group.

Results

9vHPV vaccine prevented HPV-31/33/45/52/58–related persistent infection with 90.4%–100% efficacy across included countries. At month 7, ≥97.9% of participants seroconverted for each HPV type. Injection-site AEs occurred in 77.7%–83.1% and 81.9%–87.5% of qHPV and 9vHPV vaccine recipients in Study 001, respectively, and 62.4%–85.7% of girls/boys in Study 002; most were mild to moderate.

Conclusions

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Asian participants. Data support 9vHPV vaccination programs in Asia.

Clinical Trials Registration

NCT00543543; NCT00943722.

Current issues facing the introduction of human papillomavirus vaccine in China and future prospects

The introduction of human papillomavirus (HPV) vaccination in China aims to prevent HPV infection in all women. The issues that China might face include high cost of vaccines made in other countries, shortage in HPV vaccine supply, negative events attributed to vaccination (whether justified or not) that jeopardizes the general public's confidence in the HPV vaccine, cultural and literacy barriers, and sensitivity to receiving a vaccine for a sexually transmitted disease. Ensuring the effective delivery of the HPV vaccine in China, a country with vast economic, geographical, and cultural complexities, will require a commitment of significant resources. In light of the high price of imported vaccines, the availability of locally manufactured HPV vaccines would greatly facilitate the national HPV vaccination program. New evidence supporting the efficacy of a two-dose regime in younger adolescents would also be advantageous in terms of affordability and logistical simplicity of vaccine administration. Furthermore, it would potentially enhance the compliance and uptake, especially for hard to reach women in remote regions.

Nine-valent HPV vaccine efficacy against related diseases and definitive therapy: comparison with historic placebo population

OBJECTIVE

Nine-valent human papillomavirus (9vHPV) vaccine efficacy against disease and cervical surgeries related to all nine vaccine components was assessed compared with a historic placebo population. This was not assessed in the 9vHPV vaccine efficacy trial since the trial was quadrivalent HPV (qHPV) vaccine-controlled, efficacy was measured for the five HPV types covered only by 9vHPV vaccine (HPV31/33/45/52/58), but not the four types covered by both vaccines (HPV6/11/16/18).

METHODS

Three international, randomized, double-blind studies were conducted using the same methodology. In the 9vHPV vaccine study (NCT00543543), 7106 and 7109 women received 9vHPV or qHPV vaccine, respectively. In the historic qHPV vaccine studies (FUTURE I [NCT00092521] and II [NCT00092534]), 8810 and 8812 women received qHPV vaccine or placebo, respectively, based on the same eligibility criteria. Cervical cytological testing was performed regularly. Biopsy or definitive therapy specimens were assessed for HPV DNA.

RESULTS

Among women negative for 14 HPV types prior to vaccination, incidence of high-grade cervical disease (9vHPV, n = 2 cases; placebo, n = 141 cases) and cervical surgery (9vHPV, n = 3 cases; placebo, n = 170 cases) related to the nine HPV types was reduced by 98.2% (95% confidence interval [CI], 93.6-99.7) and 97.8% (95% CI, 93.4-99.4), respectively. The 9vHPV vaccine did not prevent disease related to vaccine HPV types detected at baseline, but significantly reduced cervical, vulvar, and vaginal diseases related to other vaccine HPV types.

CONCLUSIONS

Effective implementation of the 9vHPV vaccine may substantially reduce the burden of HPV-related diseases and related medical procedures.

TRIAL REGISTRATIONS

clinicaltrials.gov: NCT00543543, NCT00092521, NCT00092534.

Expanded strain coverage for a highly successful public health tool: Prophylactic 9-valent human papillomavirus vaccine

Human papillomavirus is considered the causative factor for cervical cancer, which accounts for approximately 5% of the global cancer burden and more than 600,000 new cases annually that are attributable to HPV infection worldwide. The first-generation prophylactic HPV vaccines, Gardasil® and Cervarix®, were licensed approximately a decade ago. Both vaccines contain the most prevalent high-risk types, HPV16 and 18, which are associated with 70% of cervical cancer. To further increase the type coverage, 5 additional oncogenic HPV types (31, 33, 45, 52 and 58) were added to the existing Gardasil-4 to develop a 9-valent HPV vaccine (9vHPV), Gardasil 9®, increasing the potential level of protection from ∼70% to ∼90%. The efficacy of the vaccine lies primarily in its ability to elicit type-specific and neutralizing antibodies to fend off the viral infection. Therefore, type-specific and neutralizing murine monoclonal antibodies (mAbs) were used to quantitate the antigenicity of the individual vaccine antigens and to measure the antibody levels in the serum samples from vaccinees in a type- and epitope-specific manner in a competitive immunoassay. Assays for 9vHPV are extended from the proven platform used for 4vHPV by developing and adding new mAbs against the additional types. In Phase III clinical trials, comparable safety profile and immunogenicity against the original 4 types were demonstrated for the 9vHPV vaccine, and these were comparable to the 4vHPV vaccine. The efficacy of the 9vHPV vaccine was established in trials with young women. Immunobridging for younger boys and girls was performed, and the results showed higher immunogenicity in the younger age group. In a subsequent clinical trial, the 2-dose regimen of the 9vHPV vaccine used among girls and boys aged 9-14 y showed non-inferior immunogenicity to the regular 3-dose regimen for young women (aged 16-26 years). Overall, the clinical data and cost-effectiveness analysis for the 9vHPV vaccine support its widespread use to maximize the impact of this important, life-saving vaccine.

Efficacy, immunogenicity, and safety of a 9-valent human papillomavirus vaccine in Latin American girls, boys, and young women

BACKGROUND

A 9-valent human papillomavirus (HPV6/11/16/18/31/33/45/52/58; 9vHPV) vaccine was developed to expand coverage of the previously developed quadrivalent (HPV6/11/16/18; qHPV) vaccine.

METHODS

Efficacy, immunogenicity, and safety outcomes were assessed in Latin American participants enrolled in 2 international studies of the 9vHPV vaccine, including a randomized, double-blinded, controlled with qHPV vaccine, efficacy, immunogenicity, and safety study in young women aged 16-26 years, and an immunogenicity and safety study in girls and boys aged 9-15 years. Participants (N=5312) received vaccination at Day 1, Month 2, and Month 6. Gynecological swabs were collected regularly in young women for cytological and HPV DNA testing. Serum was analyzed for HPV antibodies in all participants. Adverse events (AEs) were also monitored in all participants.

RESULTS

The 9vHPV vaccine prevented HPV 31-, 33-, 45-, 52-, and 58-related high-grade cervical, vulvar, and vaginal dysplasia with 92.3% efficacy (95% confidence interval 54.4, 99.6). Anti-HPV6, 11, 16, and 18 geometric mean titers at Month 7 were similar in the 9vHPV and qHPV vaccination groups. Anti-HPV antibody responses following vaccination were higher among girls and boys than in young women. Most (>99%) 9vHPV vaccine recipients seroconverted for all 9 HPV types at Month 7. Antibody responses to the 9 HPV types persisted over 5 years. The most common AEs were injection-site related, mostly of mild to moderate intensity.

CONCLUSIONS

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Latin American young women, girls, and boys. These data support 9vHPV vaccination programs in Latin America, a region with substantial cervical cancer burden.

Intention-to-prevent analyses for estimating human papillomavirus vaccine efficacy in clinical studies

HPV vaccine efficacy trials have been conducted in populations exposed to HPV infection (i.e., sexually active individuals); participants were not excluded from participating in the trials based on their HPV status at baseline. Thus, some participants could have been infected at baseline with 1 or more vaccine HPV types. Because HPV vaccines are prophylactic and do not affect existing HPV infections, prophylactic efficacy was assessed in a per-protocol population (those not infected at enrollment to the HPV type being analyzed who also completed the 3-dose regimen of vaccine and had no protocol violations). Supportive intention-to-treat (ITT) and modified ITT, were also conducted to include those with prevalent HPV infection. ITT analyses included those who received ≥1 dose of vaccine and had efficacy follow-up regardless of whether or not they were infected with HPV prior to vaccination. Efficacy in the ITT population simply reflects the amount of prevalent infection in a particular population of study subjects. Intention-to-prevent (ITP) analyses included those who received one dose of vaccine, had efficacy follow-up, and were not infected at enrollment to the HPV type being analyzed.

While all of these analyses have been presented, there has been little discussion regarding their respective significance. In this methodological review, we show that an ITT analysis does not preserve an unbiased comparison of treatment groups in relation to estimating prophylactic HPV vaccine efficacy. Furthermore, ITP is more suitable at preserving an unbiased comparison of treatment groups in relation to estimating prophylactic HPV vaccine efficacy.

Final efficacy, immunogenicity, and safety analyses of a nine-valent human papillomavirus vaccine in women aged 16-26 years: a randomised, double-blind trial

BACKGROUND

Primary analyses of a study in young women aged 16-26 years showed efficacy of the nine-valent human papillomavirus (9vHPV; HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58) vaccine against infections and disease related to HPV 31, 33, 45, 52, and 58, and non-inferior HPV 6, 11, 16, and 18 antibody responses when compared with quadrivalent HPV (qHPV; HPV 6, 11, 16, and 18) vaccine. We aimed to report efficacy of the 9vHPV vaccine for up to 6 years following first administration and antibody responses over 5 years.

METHODS

We undertook this randomised, double-blind, efficacy, immunogenicity, and safety study of the 9vHPV vaccine study at 105 study sites in 18 countries. Women aged 16-26 years old who were healthy, with no history of abnormal cervical cytology, no previous abnormal cervical biopsy results, and no more than four lifetime sexual partners were randomly assigned (1:1) by central randomisation and block sizes of 2 and 2 to receive three intramuscular injections over 6 months of 9vHPV or qHPV (control) vaccine. All participants, study investigators, and study site personnel, laboratory staff, members of the sponsor's study team, and members of the adjudication pathology panel were masked to vaccination groups. The primary outcomes were incidence of high-grade cervical disease (cervical intraepithelial neoplasia grade 2 or 3, adenocarcinoma in situ, invasive cervical carcinoma), vulvar disease (vulvar intraepithelial neoplasia grade 2/3, vulvar cancer), and vaginal disease (vaginal intraepithelial neoplasia grade 2/3, vaginal cancer) related to HPV 31, 33, 45, 52, and 58 and non-inferiority (excluding a decrease of 1·5 times) of anti-HPV 6, 11, 16, and 18 geometric mean titres (GMT). Tissue samples were adjudicated for histopathology diagnosis and tested for HPV DNA. Serum antibody responses were assessed by competitive Luminex immunoassay. The primary evaluation of efficacy was a superiority analysis in the per-protocol efficacy population, supportive efficacy was analysed in the modified intention-to-treat population, and the primary evaluation of immunogenicity was a non-inferiority analysis. The trial is registered with ClinicalTrials.gov, number NCT00543543.

FINDINGS

Between Sept 26, 2007, and Dec 18, 2009, we recruited and randomly assigned 14 215 participants to receive 9vHPV (n=7106) or qHPV (n=7109) vaccine. In the per-protocol population, the incidence of high-grade cervical, vulvar and vaginal disease related to HPV 31, 33, 45, 52, and 58 was 0·5 cases per 10 000 person-years in the 9vHPV and 19·0 cases per 10 000 person-years in the qHPV groups, representing 97·4% efficacy (95% CI 85·0-99·9). HPV 6, 11, 16, and 18 GMTs were non-inferior in the 9vHPV versus qHPV group from month 1 to 3 years after vaccination. No clinically meaningful differences in serious adverse events were noted between the study groups. 11 participants died during the study follow-up period (six in the 9vHPV vaccine group and five in the qHPV vaccine group); none of the deaths were considered vaccine-related.

INTERPRETATION

The 9vHPV vaccine prevents infection, cytological abnormalities, high-grade lesions, and cervical procedures related to HPV 31, 33, 45, 52, and 58. Both the 9vHPV vaccine and qHPV vaccine had a similar immunogenicity profile with respect to HPV 6, 11, 16, and 18. Vaccine efficacy was sustained for up to 6 years. The 9vHPV vaccine could potentially provide broader coverage and prevent 90% of cervical cancer cases worldwide.

FUNDING

Merck & Co, Inc.

9-Valent human papillomavirus vaccine: a review of the clinical development program

INTRODUCTION

The 9-valent human papillomavirus (9vHPV) vaccine covers the same HPV types (6/11/16/18) as the quadrivalent HPV (qHPV) vaccine and 5 additional cancer-causing types (31/33/45/52/58). Epidemiological studies indicate that the 9vHPV vaccine could prevent approximately 90% of cervical cancers, 70-85% of high-grade cervical dysplasia (precancers), 85-95% of HPV-related vulvar, vaginal, and anal cancers, and 90% of genital warts. Areas covered: Study design features and key findings from the 9vHPV vaccine clinical development program are reviewed. In particular, 9vHPV vaccine efficacy was established in a Phase III study in young women age 16-26 years. Efficacy results in young women were extrapolated to pre- and young adolescent girls and boys and young men by immunological bridging (i.e., demonstration of non-inferior immunogenicity in these groups versus young women). Expert commentary: The development of the 9vHPV vaccine is the outcome of 20 years of continuous clinical research. Broad vaccination programs could help substantially decrease the incidence of HPV-related disease.

Human papillomavirus 9-valent vaccine for cancer prevention: a systematic review of the available evidence

In 2014, the Food and Drug Administration approved a new human papillomavirus 9-valent vaccine (9vHPV), targeting nine HPV types: HPV types 6, 11, 16, and 18, which are also targeted by the quadrivalent HPV vaccine (qHPV), plus five additional high cancer risk HPV types (HPV types 31, 33, 45, 52, and 58). The aim of the current study was to systematically retrieve, qualitatively and quantitatively pool, as well as critically appraise all available evidence on 9vHPV from randomized controlled trials (RCTs). We conducted a systematic review of the literature on 9vHPV efficacy, immunogenicity and safety, as well as a systematic search of registered, completed, and ongoing RCTs. We retrieved and screened 227 records for eligibility. A total of 10 publications reported on RCTs’ results on 9vHPV and were included in the review. Sixteen RCTs on 9vHPV have been registered on RCT registries. There is evidence that 9vHPV generated a response to HPV types 6, 11, 16 and 18 that was non-inferior to qHPV. Vaccine efficacy against five additional HPV type-related diseases was directly assessed on females aged 16–26 years (risk reduction against high-grade cervical, vulvar or vaginal disease = 96·7%, 95% CI 80·9%–99·8%). Bridging efficacy was demonstrated for males and females aged 9–15 years and males aged 16–26 years (the lower bound of the 95% CIs of both the geometric mean titer ratio and difference in seroconversion rates meeting the criteria for non-inferiority for all HPV types). Overall, 9vHPV has been proved to be safe and well tolerated. Other RCTs addressed: 9vHPV co-administration with other vaccines, 9vHPV administration in subjects that previously received qHPV and 9vHPV efficacy in regimens containing fewer than three doses. The inclusion of additional HPV types in 9vHPV offers great potential to expand protection against HPV infection. However, the impact of 9vHPV on reducing the global burden of HPV-related disease will greatly depend on vaccine uptake, coverage, availability, and affordability.

Design of a long-term follow-up effectiveness, immunogenicity and safety study of women who received the 9-valent human papillomavirus vaccine

The 9-valent human papillomavirus (HPV) (9vHPV) vaccine targets four HPV types (6/11/16/18) also covered by the quadrivalent HPV (qHPV) vaccine and five additional types (31/33/45/52/58). Vaccine efficacy to prevent HPV infection and disease was established in a Phase III clinical study in women 16-26years of age. A long-term follow-up (LTFU) study has been initiated as an extension of the Phase III clinical study to assess effectiveness of the 9vHPV vaccine up to at least 14years after the start of vaccination. It includes participants from Denmark, Norway and Sweden and uses national health registries from these countries to assess incidence of cervical pre-cancers and cancers due to the 7 oncogenic types in the vaccine (HPV 16/18/31/33/45/52/58). Incidences will be compared to the estimated incidence rate in an unvaccinated cohort of similar age and risk level. This LTFU study uses a unique design: it is an extension of a Phase III clinical study and also has elements of an epidemiological study (i.e., endpoints based on standard clinical practice; surveillance using searches from health registries); it uses a control chart method to determine whether vaccine effectiveness may be waning. Control chart methods which were developed in industrial and manufacturing settings for process and production monitoring, can be used to monitor disease incidence in real-time and promptly detect a decrease in vaccine effectiveness. Experience from this innovative study design may be applicable to other medicinal products when long-term outcomes need to be assessed, there is no control group, or outcomes are rare.

Eurogin Roadmap 2015: How has HPV knowledge changed our practice: Vaccines

This review is one of two complementary reviews that have been prepared in the framework of the Eurogin Roadmap 2015 to evaluate how knowledge about HPV is changing practices in HPV infection and disease control through vaccination and screening. In this review of HPV vaccine knowledge, we present the most significant findings of the past year which have contributed to our knowledge of the two HPV prophylactic vaccines currently in widespread use and about the recently licensed nonavalent HPV vaccine. Whereas anal cancer is dealt with in the companion mini-review on screening, we also review here the rapidly evolving evidence regarding HPV-associated head and neck cancer and priority research areas.

Safety Profile of the 9-Valent HPV Vaccine: A Combined Analysis of 7 Phase III Clinical Trials

OBJECTIVES

The overall safety profile of the 9-valent human papillomavirus (9vHPV) vaccine was evaluated across 7 Phase III studies, conducted in males and females (nonpregnant at entry), 9 to 26 years of age.

METHODS

Vaccination was administered as a 3-dose regimen at day 1, and months 2 and 6. More than 15 000 subjects received ≥1 dose of 9vHPV vaccine. In 2 of the studies, >7000 control subjects received ≥1 dose of quadrivalent HPV (qHPV) vaccine. Serious and nonserious adverse events (AEs) and new medical conditions were recorded throughout the study. Subjects testing positive for pregnancy at day 1 were not vaccinated; those who became pregnant after day 1 were discontinued from further vaccination until resolution of the pregnancy. Pregnancies detected after study start (n = 2950) were followed to outcome.

RESULTS

The most common AEs (≥5%) experienced by 9vHPV vaccine recipients were injection-site AEs (pain, swelling, erythema) and vaccine-related systemic AEs (headache, pyrexia). Injection-site AEs were more common in 9vHPV vaccine than qHPV vaccine recipients; most were mild-to-moderate in intensity. Discontinuations and vaccine-related serious AEs were rare (0.1% and <0.1%, respectively). Seven deaths were reported; none were considered vaccine related. The proportions of pregnancies with adverse outcome were within ranges reported in the general population.

CONCLUSIONS

The 9vHPV vaccine was generally well tolerated in subjects aged 9 to 26 years with an AE profile similar to that of the qHPV vaccine; injection-site AEs were more common with 9vHPV vaccine. Its additional coverage and safety profile support widespread 9vHPV vaccination.

A phase III clinical study to compare the immunogenicity and safety of the 9-valent and quadrivalent HPV vaccines in men

BACKGROUND

A nine-valent human papilloma virus (9vHPV) vaccine has been developed to prevent infections and diseases related to HPV 6/11/16/18 (as per the licensed quadrivalent HPV (qHPV) vaccine) as well as to five additional oncogenic HPV types (HPV 31/33/45/52/58). The 9vHPV vaccine has the potential to prevent 90% of cervical cancers, HPV-related anal, vaginal and vulval cancers and anogenital warts. We compared the immunogenicity and safety of the 9vHPV vaccine versus the qHPV vaccine in 16-26-year-old men.

METHODS

Participants (N=500) were randomised to receive 9vHPV or qHPV vaccines on day 1, month 2 and month 6. Serology testing was performed on day 1 and month 7. HPV type-specific antibody titres (anti-HPV 6/11/16/18/31/33/45/52/58) were determined by competitive Luminex immunoassay and expressed as geometric mean titres and seroconversion rates. Vaccine safety was also assessed.

RESULTS

The HPV 6/11/16/18 immune responses elicited by the 9vHPV vaccine were comparable with those elicited by the qHPV vaccine. All participants receiving the 9vHPV vaccine seroconverted for HPV 31/33/45/52/58. The 9vHPV and qHPV vaccines showed comparable safety profiles.

CONCLUSIONS

In addition to immune responses to HPV 31/33/45/52/58, a three-dose regimen of the 9vHPV vaccine elicited a similar immune response to HPV 6/11/16/18 when compared with the qHPV vaccine in men aged 16-26years. The safety profile was also similar for the two vaccines. The results from this study support extending the efficacy findings with qHPV vaccine to 9vHPV vaccine in men aged 16-26years. NCT02114385.

Deconstructing the measure of vaccine efficacy against disease irrespective of HPV in HPV vaccine clinical trials

BACKGROUND

Human papillomavirus (HPV) vaccines were licensed by demonstrating prevention of anogenital disease caused by specific HPV types in clinical studies. Measuring the impact of HPV vaccination on the overall burden of anogenital disease (irrespective of HPV) is an important public health question which is ideally addressed in post-licensure epidemiological studies. Attempts were made to use clinical trial data for that purpose. However, the interpretation of vaccine efficacy on the endpoint of disease irrespective of HPV is not widely understood.

METHODS

We used the 9-valent HPV vaccine clinical program as a case study to determine the value of measuring vaccine efficacy in such endpoint. This assessment was rigorously performed by heuristic reasoning and through probability calculations.

RESULTS

The measure of vaccine efficacy in the irrespective of HPV endpoint is driven simultaneously in opposite directions by the high estimate of prophylactic efficacy and a numerically negative estimate of risk reduction that is also a reflection of high prophylactic efficacy and no cross-protection.

CONCLUSIONS

The vaccine efficacy estimate in the irrespective of HPV endpoint is ambiguous and difficult to interpret. Comparing this estimate across different HPV vaccine studies requires an understanding of the contributions of vaccine HPV type efficacy and the incidence of disease not related to vaccine HPV types for each study. Without such understanding, comparing studies and drawing conclusions from such comparison are highly misleading. Approaches are proposed to divide this endpoint in components that are easier to interpret.

9-Valent HPV vaccine for cancers, pre-cancers and genital warts related to HPV

Human papillomavirus (HPV) is the causative agent of nearly all cervical cancer cases as well as a substantial proportion of anal, vulvar, vaginal, penile and oropharyngeal cancers, making it responsible for approximately 5% of the global cancer burden. The first-generation HPV vaccines that is, quadrivalent HPV type 6/11/16/18 vaccine and bivalent HPV type 16/18 vaccine were licensed in 2006 and 2007, respectively. A second-generation 9-valent HPV type 6/11/16/18/31/33/45/52/58 vaccine with broader cancer coverage was initiated even before the first vaccines were approved. By preventing HPV infection and disease due to HPV31/33/45/52/58, the 9vHPV vaccine has the potential to increase prevention of cervical cancer from 70 to 90%. In addition, the 9vHPV vaccine has the potential to prevent 85-95% of HPV-related vulvar, vaginal and anal cancers. Overall, the 9vHPV vaccine addresses a significant unmet medical need, although further health economics and implementation research is needed.