A summary of the post-licensure surveillance initiatives for GARDASIL/SILGARD®

Human Papillomavirus Vaccination and Premature Ovarian Failure: A Disproportionality Analysis Using the Vaccine Adverse Event Reporting System

INTRODUCTION

There have been public health concerns about a potential association between human papillomavirus (HPV) vaccines and premature ovarian failure (POF) in young women.

OBJECTIVE

To identify a potential safety signal of POF after HPV vaccination using the United States (US) Vaccine Adverse Event Reporting System (VAERS) database.

METHODS

We manually selected relevant MedDRA preferred terms related to POF and identified in VAERS all POF reports in women less than 40 years of age between 2 July 1990 and 14 May 2018, followed by a review of narratives to confirm the cases. We conducted descriptive analyses on age, POF type, HPV vaccine type (HPV2, HPV4, HPV9), time to onset of POF, and dose rank. We described trends in reporting over time and assessed a potential safety signal using the proportional reporting ratio (PRR).

RESULTS

Of the 228,341 eligible POF reports, 281 (0.1%) were suspected to be associated with HPV vaccines. Median patient age was 15 years (range 11-39 years). POF events consisted mainly of amenorrhea (80.4%) and premature menopause (15.3%). Mean number of reported POF events significantly increased after the first HPV vaccine launch in 2006 with 22.2 POF cases/year up from 1.4 POF cases/year before the launch. PRR was 46.1 (95% confidence interval: 31.7-67.2) and sensitivity analyses yielded similar estimates.

CONCLUSION

Our study suggests the presence of a potential safety signal of POF associated with HPV vaccination, which may only be partly attributed to notoriety bias. Due to the well-known limitations of spontaneous reporting data, further investigations are warranted.

Vaccinations and Autoimmune Diseases

Vaccines represent one of the most effective measures of public health medicine, saving countless lives and preventing lifelong disabilities. Vaccines are extremely safe, however, no vaccine is completely free from risks and adverse events can occur following vaccination. An adverse event following immunization (AEFI) may be a true adverse reaction caused by the vaccine or an event that temporally occurred after immunization but is not caused by it. Among the adverse reactions to vaccines, one of the most feared is the triggering of autoimmune diseases, which are a heterogeneous group of disorders characterized by dysregulation of the immune system. Currently, no mechanisms have been demonstrated that could explain the correlation between vaccination and the development of autoimmune diseases. Furthermore, epidemiological studies do not support the hypothesis that vaccines cause systemic autoimmune diseases. The only confirmed associations, although very rare, are those between the flu vaccine and Guillain-Barré syndrome, especially with old vaccine preparations, and measles-mumps-rubella (MMR) vaccine and thrombocytopenia. Due to the SARS-CoV2 pandemic, new types of vaccines have been developed and are now available. Close vaccine safety-surveillance is currently underway for these new vaccines.

Human papillomavirus vaccine and demyelinating diseases-A systematic review and meta-analysis

Approved in 2006, human papillomavirus (HPV) vaccines were initially targeted for girls aged 9-14 years. Although the safety of these vaccines has been monitored through post-licensure surveillance programmes, cases of neurological events have been reported worldwide. The present study aimed to assess the risk of developing demyelination after HPV immunization by meta-analysing risk estimates from pharmacoepidemiologic studies. A systematic review was conducted in Medline, Embase, ISI Web of Science and the Cochrane Library from inception to 10 May 2017, without language restriction. Only observational studies including a control group were retained. Study selection was performed by two independent reviewers with disagreements solved through discussion. This meta-analysis was performed using a generic inverse variance random-effect model. Outcomes of interest included a broad category of central demyelination, multiple sclerosis (MS), optic neuritis (ON), and Guillain-Barré syndrome (GBS), each being considered independently. Heterogeneity was investigated; sensitivity and subgroup analyses were performed when necessary. In parallel, post-licensure safety studies were considered for a qualitative review. This study followed the PRISMA statement and the MOOSE reporting guideline. Of the 2,863 references identified, 11 articles were selected for meta-analysis. No significant association emerged between HPV vaccination and central demyelination, the pooled odds ratio being 0.96 [95% CI 0.77-1.20], with a moderate but non-significant heterogeneity (I² = 29%). Similar results were found for MS and ON. Sensitivity analyses did not alter our conclusions. Findings from qualitative review of 14 safety studies concluded in an absence of a relevant signal. Owing to limited data on GBS, no meta-analysis was performed for this outcome. This study strongly supports the absence of association between HPV vaccines and central demyelination.

Strengthening the case for gender-neutral and the nonavalent HPV vaccine

PURPOSE

The purpose of this review is to highlight the benefits of gender-neutral and the nonavalent human papillomavirus vaccination. Human papillomavirus infection is the most commonly sexually transmitted disease and is known to cause several types of cancers, including cervical, vulvar, vaginal, penile, oropharyngeal, anal, and rectal. 5% of cancers every year are attributable to human papillomavirus infection, with cervical cancer the most common and oropharyngeal cancer estimated to surpass the incidence of cervical cancer by 2020.

METHODS

PubMed and MEDLINE were searched using the following search terms: [(human papillomavirus OR HPV) AND (vaccine OR vaccination)] AND [(gardasil OR gardasil9 OR cervarix OR quadrivalent OR nonavalent OR ninevalent) OR (gender neutral OR male)].

RESULTS

There are currently three different types of human papillomavirus vaccinations and range in cover from four to nine different strains known to cause human disease. Most countries currently only supply vaccination to females; however, recent data point towards both a personal benefit as well as a cost-effective population-based benefit with gender-neutral vaccination. Data from female vaccination only have shown the vaccine to be effective in preventing premalignant cervical lesions, and are believed to have the same effect for other human papillomavirus cancers. Male vaccination not only provides personal benefit but also has a "herd effect" for females by preventing the propagation of the virus.

CONCLUSION

Gender-neutral vaccination provides significant cost-effective benefits for preventing human papillomavirus-related diseases, and this effect is further enhanced by the use of the nonavalent vaccine.

Monitoring the impact of HPV vaccine in males-Considerations and challenges

In this article, we examine the issues involved if national or sub-national programs are considering extending post HPV vaccine introduction monitoring to include males. Vaccination programs are now being extended to include males in some countries, in order to improve population level HPV infection control and to directly prevent HPV-related disease in males such as anogenital warts and anal cancers. Coverage and adverse events surveillance are essential components of post-vaccination monitoring. Monitoring the impact of vaccination on HPV infection and disease in men raises some similar challenges to monitoring in females, such as the long time frame until cancer outcomes, and also different ones given that genital specimens suitable for monitoring HPV prevalence are not routinely collected for other diagnostic or screening purposes in males. Thus, dedicated surveillance strategies must be designed; the framework of these may be country-specific, dependent upon the male population that is offered vaccination, the health care infrastructure and existing models of disease surveillance such as STI networks. The primary objective of any male HPV surveillance program will be to document changes in the prevalence of HPV infection and disease due to vaccine targeted HPV types occurring post vaccination. The full spectrum of outcomes to be considered for inclusion in any surveillance plan includes HPV prevalence monitoring, anogenital warts, potentially pre-cancerous lesions such as anal squamous intraepithelial lesions (SIL), and cancers. Ideally, a combination of short term and long term outcome measures would be included. Surveillance over time in specific targeted populations of men who have sex with men and HIV-infected men (populations at high risk for HPV infection and associated disease) could be an efficient use of resources to demonstrate impact.

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Males surveillance can provide information about both herd protection and direct impact.

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Dedicated specimen collection is needed for HPV prevalence surveillance in males.

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Anogenital wart monitoring is a useful early indicator of HPV vaccine impact.

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Trends in HPV-related male cancers will be the ultimate indicator of success.

Safety assessment of adjuvanted vaccines: Methodological considerations

Adjuvants mainly interact with the innate immune response and are used to enhance the quantity and quality of the downstream adaptive immune response to vaccine antigens. Establishing the safety of a new adjuvant-antigen combination is achieved through rigorous evaluation that begins in the laboratory, and that continues throughout the vaccine life-cycle. The strategy for the evaluation of safety pre-licensure is guided by the disease profile, vaccine indication, and target population, and it is also influenced by available regulatory guidelines. In order to allow meaningful interpretation of clinical data, clinical program methodology should be optimized and standardized, making best use of all available data sources. Post-licensure safety activities are directed by field experience accumulated pre- and post-licensure clinical trial data and spontaneous adverse event reports. Continued evolution of safety evaluation processes that keep pace with advances in vaccine technology and updated communication of the benefit-risk profile is necessary to maintain public confidence in vaccines.

Quadrivalent HPV vaccine safety review and safety monitoring plans for nine-valent HPV vaccine in the United States

Quadrivalent human papillomavirus (4vHPV) vaccine was licensed for use in the United States in 2006 and through 2015 was the predominate HPV vaccine used. With the exception of syncope, a known preventable adverse event after any injected vaccination, both pre-licensure and post-licensure 4vHPV safety data have been reassuring with no confirmed safety signals identified. Nine-valent HPV vaccine (9vHPV) was licensed in 2014. This review includes post-licensure 4vHPV safety findings published to date that have informed the US vaccination program; these data will inform US safety monitoring and evaluation for 9vHPV.

An Overview of Quadrivalent Human Papillomavirus Vaccine Safety: 2006 to 2015

BACKGROUND

A quadrivalent human papillomavirus (HPV4) type 6/11/16/18 vaccine (GARDASIL/SILGARD®) has been licensed in many countries around the world for the prevention of cervical, vulvar, vaginal, and anal cancers and precancers, as well as external genital warts causally related to HPV types 6/11/16/18. Across 7 phase 3 clinical trials involving more than 29,000 males and females ages 9-45 years, vaccination was generally well tolerated. Because of its expected public health benefit in reducing cervical cancer and other HPV-related diseases, the vaccine has been implemented in the national vaccination programs of several countries, with over 178 million doses distributed worldwide.

METHODS

Extensive efforts to assess the safety of the vaccine in routine practice have been conducted over the past 9 years since licensure, including more than 15 studies in more than 1 million preadolescents, adolescents and adults from various countries. Most have been performed in the general population although there have been some in special populations (pregnant women, HIV-infected individuals and those with systemic lupus erythematosus).

RESULTS

We present a summary of the published, postlicensure safety data from active and passive surveillance. Only syncope, and possibly skin infections were associated with vaccination in the postlicensure setting. Serious adverse events, such as adverse pregnancy outcomes, autoimmune diseases (including Guillain-Barre Syndrome and multiple sclerosis), anaphylaxis, venous thromboembolism and stroke, were extensively studied, and no increase in the incidence of these events was found compared with background rates.

CONCLUSIONS

These results, along with the safety data from the prelicensure clinical trials, confirm that the HPV4 vaccine has a favorable safety profile. Key policy, medical and regulatory organizations around the world have independently reviewed these data and continue to recommend routine HPV vaccination.

Quadrivalent human papillomavirus (types 6, 11, 16, 18) recombinant vaccine (gardasil(®)): a review of its use in the prevention of premalignant anogenital lesions, cervical and anal cancers, and genital warts

Quadrivalent human papillomavirus (HPV) [types 6, 11, 16, 18] recombinant vaccine (Gardasil(®); Silgard(®)) is composed of virus-like particles formed by self-assembly of recombinant L1 capsid protein from each of HPV types 6, 11, 16 and 18. It is indicated for use from the age of 9 years as a two- or three-dose vaccination course over 6 months for the prevention of premalignant anogenital lesions, cervical and anal cancers, and genital warts caused by the vaccine HPV types. In placebo-controlled trials, quadrivalent HPV vaccine provided high-level protection against infection or disease caused by the vaccine HPV types over 2-4 years in females aged 15-45 years who were negative for the vaccine HPV types, and provided a degree of cross-protection against certain non-vaccine HPV types. The vaccine also provided high-level protection against persistent infection, anogenital precancerous lesions and genital warts caused by the vaccine HPV types over 3 years in susceptible males aged 16-26 years. Protection has been demonstrated for up to 8 years. In subjects who were negative for the vaccine HPV types, high seroconversion rates and high levels of anti-HPV antibodies were observed in females of all age ranges from 9 to 45 years and in males aged 9-26 years. The vaccine was generally well tolerated and was usually predicted to be cost effective in girls and young women. Therefore, quadrivalent HPV vaccine offers an effective means to substantially reduce the burden of HPV-related anogenital disease in females and males, particularly cervical cancer and genital warts.

Vaccine Adjuvants: from 1920 to 2015 and Beyond

The concept of stimulating the body’s immune response is the basis underlying vaccination. Vaccines act by initiating the innate immune response and activating antigen presenting cells (APCs), thereby inducing a protective adaptive immune response to a pathogen antigen. Adjuvants are substances added to vaccines to enhance the immunogenicity of highly purified antigens that have insufficient immunostimulatory capabilities, and have been used in human vaccines for more than 90 years. While early adjuvants (aluminum, oil-in-water emulsions) were used empirically, rapidly increasing knowledge on how the immune system interacts with pathogens means that there is increased understanding of the role of adjuvants and how the formulation of modern vaccines can be better tailored towards the desired clinical benefit. Continuing safety evaluation of licensed vaccines containing adjuvants/adjuvant systems suggests that their individual benefit-risk profile remains favorable. Adjuvants contribute to the initiation of the innate immune response induced by antigens; exemplified by inflammatory responses at the injection site, with mostly localized and short-lived effects. Activated effectors (such as APCs) then move to draining lymph nodes where they direct the type, magnitude and quality of the adaptive immune response. Thus, the right match of antigens and adjuvants can potentiate downstream adaptive immune responses, enabling the development of new efficacious vaccines. Many infectious diseases of worldwide significance are not currently preventable by vaccination. Adjuvants are the most advanced new technology in the search for new vaccines against challenging pathogens and for vulnerable populations that respond poorly to traditional vaccines.

Vaccine Adjuvants: from 1920 to 2015 and Beyond

The concept of stimulating the body's immune response is the basis underlying vaccination. Vaccines act by initiating the innate immune response and activating antigen presenting cells (APCs), thereby inducing a protective adaptive immune response to a pathogen antigen. Adjuvants are substances added to vaccines to enhance the immunogenicity of highly purified antigens that have insufficient immunostimulatory capabilities, and have been used in human vaccines for more than 90 years. While early adjuvants (aluminum, oil-in-water emulsions) were used empirically, rapidly increasing knowledge on how the immune system interacts with pathogens means that there is increased understanding of the role of adjuvants and how the formulation of modern vaccines can be better tailored towards the desired clinical benefit. Continuing safety evaluation of licensed vaccines containing adjuvants/adjuvant systems suggests that their individual benefit-risk profile remains favorable. Adjuvants contribute to the initiation of the innate immune response induced by antigens; exemplified by inflammatory responses at the injection site, with mostly localized and short-lived effects. Activated effectors (such as APCs) then move to draining lymph nodes where they direct the type, magnitude and quality of the adaptive immune response. Thus, the right match of antigens and adjuvants can potentiate downstream adaptive immune responses, enabling the development of new efficacious vaccines. Many infectious diseases of worldwide significance are not currently preventable by vaccination. Adjuvants are the most advanced new technology in the search for new vaccines against challenging pathogens and for vulnerable populations that respond poorly to traditional vaccines.

Evaluation of human papillomavirus DNA detection in samples obtained for routine Chlamydia trachomatis screening

BACKGROUND

The costs and logistics involved in obtaining samples is a bottleneck in large-scale studies of the circulation of human papillomavirus (HPV), which are useful for monitoring and optimisation of HPV-vaccination programs. Residual samples obtained after screening for Chlamydia trachomatis could constitute a convenient, low-cost solution.

OBJECTIVES

We evaluated HPV DNA detection and typing using (i) the residual samples routinely taken for C. trachomatis screening or (ii) the sample types used in large-scale phase III HPV vaccination trials (cervical, vulvar, labial, perineal, perianal, scrotal and penile shaft samples).

STUDY DESIGN

Samples from 127 men and 110 women attending two sexual health clinics were analysed using PCR for HPV DNA, with typing using mass spectrometry.

RESULTS

The HPV DNA prevalence was 7.1% in male urine samples, but 57.3% in female urine/vaginal samples, which was even higher than the HPV prevalence found in cervical samples (54.1%). The sensitivity for HPV DNA detection in the urine/vaginal samples was 7.9% (95% CI 3.0-16.4) for men and 78.9% (95% CI 67.6-87.7) for women, using detection in any one of the reference samples as reference. With cervical samples as reference, the sensitivity was 89.3 % (95% CI 78.1-95.9).

CONCLUSIONS

Among men, low sensitivity of urine for HPV detection suggests limited usefulness. Among women, the high sensitivity of urine/vaginal samples for HPV detection suggests a useful low-cost solution for the study of HPV epidemiology.

Parents' decision-making about the human papillomavirus vaccine for their daughters: I. Quantitative results

Vaccination against the human papillomavirus (HPV) is an effective primary prevention measure for HPV-related diseases. For children and young adolescents, the uptake of the vaccine is contingent on parental consent. This study sought to identify key differences between parents who obtain (acceptors) and parents who refuse (non-acceptors) the HPV vaccine for their daughters. In the context of a free, universal, school-based HPV vaccination program in Québec, 774 parents of 9-10 year-old girls completed and returned a questionnaire by mail. The questionnaire was based on the theoretical constructs of the Health Belief Model (HBM), along with constructs from other theoretical frameworks. Of the 774 parents, 88.2% reported their daughter having received the HPV vaccine. Perceived susceptibility of daughters to HPV infection, perceived benefits of the vaccine, perceived barriers (including safety of the vaccine), and cues to action significantly distinguished between parents whose daughters had received the HPV vaccine and those whose daughters had not. Other significant factors associated with daughter vaccine uptake were parents' general vaccination attitudes, anticipated regret, adherence to other routinely recommended vaccines, social norms, and positive media influence. The results of this study identify a number of important correlates related to parents' decisions to accept or refuse the HPV vaccine uptake for their daughters. Future work may benefit from targeting such factors and incorporating other health behavior theories in the design of effective HPV vaccine uptake interventions.

Adolescent Premature Ovarian Insufficiency Following Human Papillomavirus Vaccination: A Case Series Seen in General Practice

Three young women who developed premature ovarian insufficiency following quadrivalent human papillomavirus (HPV) vaccination presented to a general practitioner in rural New South Wales, Australia. The unrelated girls were aged 16, 16, and 18 years at diagnosis. Each had received HPV vaccinations prior to the onset of ovarian decline. Vaccinations had been administered in different regions of the state of New South Wales and the 3 girls lived in different towns in that state. Each had been prescribed the oral contraceptive pill to treat menstrual cycle abnormalities prior to investigation and diagnosis. Vaccine research does not present an ovary histology report of tested rats but does present a testicular histology report. Enduring ovarian capacity and duration of function following vaccination is unresearched in preclinical studies, clinical and postlicensure studies. Postmarketing surveillance does not accurately represent diagnoses in adverse event notifications and can neither represent unnotified cases nor compare incident statistics with vaccine course administration rates. The potential significance of a case series of adolescents with idiopathic premature ovarian insufficiency following HPV vaccination presenting to a general practice warrants further research. Preservation of reproductive health is a primary concern in the recipient target group. Since this group includes all prepubertal and pubertal young women, demonstration of ongoing, uncompromised safety for the ovary is urgently required. This matter needs to be resolved for the purposes of population health and public vaccine confidence.

Towards the eradication of HPV infection through universal specific vaccination

BACKGROUND

The Human Papillomavirus (HPV) is generally recognized to be the direct cause of cervical cancer. The development of effective anti-HPV vaccines, included in the portfolio of recommended vaccinations for any given community, led to the consolidation in many countries of immunization programs to prevent HPV-related cervical cancers. In recent years, increasing evidence in epidemiology and molecular biology have supported the oncogenic role of HPV in the development of other neoplasm including condylomas and penile, anal, vulvar, vaginal, and oro-pharyngeal cancers. Men play a key role in the paradigm of HPV infection: both as patients and as part of the mechanisms of transmission. Data show they are affected almost as often as women. Moreover, no screening procedures for HPV-related disease prevention are applied in men, who fail to undergo routine medical testing by any medical specialist at all. They also do not benefit from government prevention strategies.

DISCUSSION

A panel of experts convened to focus on scientific, medical, and economic studies, and on the achievements from health organizations' intervention programs on the matter. One of the goals was to discuss on the critical issues emerging from the ongoing global implementation of HPV vaccination. A second goal was to identify contributions which could overcome the barriers that impede or delay effective vaccination programs whose purpose is to eradicate the HPV infection both in women and men.

SUMMARY

The reviewed studies on the natural history of HPV infection and related diseases in women and men, the increasing experience of HPV vaccination in women, the analysis of clinical effectiveness vs economic efficacy of HPV vaccination, are even more supportive of the economic sustainability of vaccination programs both in women and men. Those achievements address increasing and needed attention to the issue of social equity in healthcare for both genders.

Primary prophylactic human papillomavirus vaccination programs: future perspective on global impact

Of the 40 types of human papillomavirus that can infect the mucosal epithelium, four types can now be prevented using prophylactic vaccination. Two of these types (high-risk types 16 and 18) cause 70% of cervical cancers, a proportion of other genital cancers and a subset of head and neck cancers. The low-risk types 6 and 11 cause 90% of genital warts and the disease recurrent respiratory papillomatosis. Thus, if primary HPV vaccination programs can be implemented effectively, the potential for a reduction in global disease burden is great. This article considers the current issues and challenges in delivering primary HPV vaccination programs effectively and the likely impact of the vaccines in both the near and more distant future.

Reduction in human papillomavirus (HPV) prevalence among young women following HPV vaccine introduction in the United States, National Health and Nutrition Examination Surveys, 2003-2010

BACKGROUND

Human papillomavirus (HPV) vaccination was introduced into the routine immunization schedule in the United States in late 2006 for females aged 11 or 12 years, with catch-up vaccination recommended for those aged 13-26 years. In 2010, 3-dose vaccine coverage was only 32% among 13-17 year-olds. Reduction in the prevalence of HPV types targeted by the quadrivalent vaccine (HPV-6, -11, -16, and -18) will be one of the first measures of vaccine impact.

METHODS

We analyzed HPV prevalence data from the vaccine era (2007-2010) and the prevaccine era (2003-2006) that were collected during National Health and Nutrition Examination Surveys. HPV prevalence was determined by the Linear Array HPV Assay in cervicovaginal swab samples from females aged 14-59 years; 4150 provided samples in 2003-2006, and 4253 provided samples in 2007-2010.

RESULTS

Among females aged 14-19 years, the vaccine-type HPV prevalence (HPV-6, -11, -16, or -18) decreased from 11.5% (95% confidence interval [CI], 9.2-14.4) in 2003-2006 to 5.1% (95% CI, 3.8-6.6) in 2007-2010, a decline of 56% (95% CI, 38-69). Among other age groups, the prevalence did not differ significantly between the 2 time periods (P > .05). The vaccine effectiveness of at least 1 dose was 82% (95% CI, 53-93).

CONCLUSIONS

Within 4 years of vaccine introduction, the vaccine-type HPV prevalence decreased among females aged 14-19 years despite low vaccine uptake. The estimated vaccine effectiveness was high.

HPV vaccination and cervical cancer

Cervical cancer is the third most common cancer in women worldwide and often affects women under 40 years with young families. Vaccination against the human papillomavirus (HPV) is a major advance, since it offers primary prevention against the infectious agent that is the main cause of the disease. Two prophylactic vaccines have shown great promise in clinical trials. One of these (Gardasil(®)) contains all four HPV types, offering protection against genital warts (types 6 and 11) as well as cervical cancer (types 16 and 18). The other (Cervarix(®)) contains types 16 and 18, targeting cervical cancer alone, but also has a degree of cross-protection against types 31 and 45, which could significantly increase the level of protection. Adolescent girls remain the primary target of vaccination programmes, but the issues of vaccinating boys and older women are increasingly debated.

Human papillomavirus vaccine introduction--the first five years

The availability of prophylactic human papillomavirus (HPV) vaccines has provided powerful tools for primary prevention of cervical cancer and other HPV-associated diseases. Since 2006, the quadrivalent and bivalent vaccines have each been licensed in over 100 countries. By the beginning of 2012, HPV vaccine had been introduced into national immunization programs in at least 40 countries. Australia, the United Kingdom, the United States, and Canada were among the first countries to introduce HPV vaccination. In Europe, the number of countries having introduced vaccine increased from 3 in 2007 to 22 at the beginning of 2012. While all country programs target young adolescent girls, specific target age groups vary as do catch-up recommendations. Different health care systems and infrastructure have resulted in varied implementation strategies, with some countries delivering vaccine in schools and others through health centers or primary care providers. Within the first 5 years after vaccines became available, few low- or middle-income countries had introduced HPV vaccine. The main reason was budgetary constraints due to the high vaccine cost. Bhutan and Rwanda implemented national immunization after receiving vaccine through donation programs in 2010 and 2011, respectively. The GAVI Alliance decision in 2011 to support HPV vaccination should increase implementation in low-income countries. Evaluation of vaccination programs includes monitoring of coverage, safety, and impact. Vaccine safety monitoring is part of routine activities in many countries. Safety evaluations are important and communication about vaccine safety is critical, as events temporally associated with vaccination can be falsely attributed to vaccination. Anti-vaccination efforts, in part related to concerns about safety, have been mounted in several countries. In the 5 years since HPV vaccines were licensed, there have been successes as well as challenges with vaccine introduction and implementation. Further progress is anticipated in the coming years, especially in low- and middle-income countries where the need for vaccine is greatest. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Clinical trial experience with prophylactic human papillomavirus 6/11/16/18 vaccine in young black women

PURPOSE

Human papillomavirus (HPV) is the causative agent of cervical cancer. Black women are disproportionally diagnosed and have higher mortality from cervical cancer in the United States. Here we describe the prophylactic efficacy and safety of a quadrivalent HPV-6/11/16/18 vaccine in black women.

METHODS

A total of 700 black women from Latin America, Europe, and North America (aged 16-24 years) received the vaccine or placebo in one of two studies. Analyses focused on the efficacy and safety of the vaccine.

RESULTS

Baseline rates of Chlamydia trachomatis infection and history of past pregnancy were more than twice as high in black women compared with the non-black women who were enrolled in these trials. HPV-6/11/16 or 18 DNA was detected in 18% of black women versus 14.6% in non-black women at day 1. For black women, vaccine efficacy against disease caused by HPV-6/11/16/18 was 100% for cervical intraepithelial neoplasia (0 vs. 15 cases; 95% confidence interval, 64.5%-100%) and 100% for vulvar and vaginal intraepithelial neoplasia and condylomata acuminata (0 vs. 17 cases; 95% confidence interval, 69.3%-100%). There were no serious vaccine-related adverse experiences. A similar proportion of pregnancies resulted in live births (75.8% vaccine; 72.7% placebo) and fetal loss (24.2% vaccine; 27.3% placebo).

CONCLUSIONS

Prophylactic quadrivalent HPV-6/11/16/18 vaccination of young black women demonstrated high efficacy, safety, and tolerability. HPV vaccination has the potential to reduce cervical cancer-related health disparities both in the United States and around the world.

A review of clinical trials of human papillomavirus prophylactic vaccines

End of study analyses of the phase III trials of prophylactic human papillomavirus (HPV) virus-like particle (VLP) vaccines in young women are now largely completed. Two distinct vaccines were evaluated, Gardasil(®) (Merck & Co., Whitehouse Station, NJ USA) a quadrivalent vaccine containing VLPs of types 6, 11, 16 and 18 and Cervarix(®) (GlaxoSmithKline Biologicals, Rixensart, Belgium), a bivalent vaccine containing VLPs of types 16 and 18. Both vaccines exhibited excellent safety and immunogenicity profiles. The vaccines also demonstrated remarkably high and similar efficacy against the vaccine-targeted types for a range of cervical endpoints from persistent infection to cervical intraepithelial neoplasia grade 3 (CIN3) in women naïve to the corresponding type at the time of vaccination. However, protection from incident infection or disease from non-vaccine types was restricted, and the vaccines had no effect on prevalent infection or disease. Gardasil(®) also demonstrated strong protection against genital warts and vulvar/vaginal neoplasia associated with the vaccine types. In other trials, Gardasil(®) protected mid-adult women from incident infection and CIN caused by the vaccine types and protected men for incident infection, genital warts and anal intraepithelial neoplasia by the vaccine types. Cervarix(®) protected against vaccine-targeted anal infections in women in an end of study evaluation. For practical reasons, efficacy studies have not been conducted in the primary target populations of current vaccination programs, adolescent girls and boys. However, immunogenicity bridging studies demonstrating excellent safety and strong immune responses in adolescence, coupled with the documentation of durable antibody responses and protection in young adults, leads to an optimistic projection of the effectiveness of the vaccines in adolescent vaccination programs. Taken together, the excellent clinical trial results strongly support the potential of the vaccines as high value public health interventions and justify their widespread implementation to prevent anogenital HPV infections and their associated neoplasia. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Effect of the human papillomavirus (HPV) quadrivalent vaccine in a subgroup of women with cervical and vulvar disease: retrospective pooled analysis of trial data

OBJECTIVES

To determine the effect of human papillomavirus (HPV) quadrivalent vaccine on the risk of developing subsequent disease after an excisional procedure for cervical intraepithelial neoplasia or diagnosis of genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia.

DESIGN

Retrospective analysis of data from two international, double blind, placebo controlled, randomised efficacy trials of quadrivalent HPV vaccine (protocol 013 (FUTURE I) and protocol 015 (FUTURE II)).

SETTING

Primary care centres and university or hospital associated health centres in 24 countries and territories around the world.

PARTICIPANTS

Among 17,622 women aged 15-26 years who underwent 1:1 randomisation to vaccine or placebo, 2054 received cervical surgery or were diagnosed with genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia.

INTERVENTION

Three doses of quadrivalent HPV vaccine or placebo at day 1, month 2, and month 6.

MAIN OUTCOME MEASURES

Incidence of HPV related disease from 60 days after treatment or diagnosis, expressed as the number of women with an end point per 100 person years at risk.

RESULTS

A total of 587 vaccine and 763 placebo recipients underwent cervical surgery. The incidence of any subsequent HPV related disease was 6.6 and 12.2 in vaccine and placebo recipients respectively (46.2% reduction (95% confidence interval 22.5% to 63.2%) with vaccination). Vaccination was associated with a significant reduction in risk of any subsequent high grade disease of the cervix by 64.9% (20.1% to 86.3%). A total of 229 vaccine recipients and 475 placebo recipients were diagnosed with genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia, and the incidence of any subsequent HPV related disease was 20.1 and 31.0 in vaccine and placebo recipients respectively (35.2% reduction (13.8% to 51.8%)).

CONCLUSIONS

Previous vaccination with quadrivalent HPV vaccine among women who had surgical treatment for HPV related disease significantly reduced the incidence of subsequent HPV related disease, including high grade disease.

TRIAL REGISTRATIONS

NCT00092521 and NCT00092534.

The efficacy and safety of the quadrivalent human papillomavirus 6/11/16/18 vaccine gardasil

Human papillomavirus (HPV) infection causes cervical cancer, a significant portion of anal, genital, and oropharyngeal cancers, genital warts, and recurrent respiratory papillomatosis. In June 2006, a quadrivalent HPV-6/11/16/18 vaccine (Gardasil/Silgard) was licensed in the United States, and subsequently in the European Union (September 2006). It has since been approved in 121 countries, with >74 million doses distributed globally as of March 2011. As the incidence of HPV infection peaks 5-10 years after the onset of sexual activity, preadolescents and adolescents represent an appropriate target group to implement HPV vaccination programs so as to achieve the maximal public health benefit. In this article, we provide an overview of the prophylactic efficacy of the vaccine in young women who were found to be negative to at least one of the four vaccine HPV types, thus approximating sexually naive adolescents. Because adolescents are also at high risk for other infections which are preventable by currently available vaccines, the development of concurrent immunization strategies may lead to better compliance, thereby contributing to the overall goal of protection against preventable diseases. We also summarize concomitant administration studies with meningococcal, diphtheria, tetanus, and pertussis vaccines, which were conducted in adolescents aged 9-15 years. Prophylactic efficacy in other populations (males aged 16-26 years) is also summarized along with long-term safety and efficacy studies.

Paradigm shifting vaccines: prophylactic vaccines against latent varicella-zoster virus infection and against HPV-associated cancer

We compare the design, mechanism of action, and clinical efficacy of two recently licensed paradigm shifting vaccines. Zostavax is the first vaccine licensed to prevent disease in patients already infected with a pathogen, and is contrasted with Gardasil and Cervarix, the first vaccines designed and licensed specifically to prevent cancers.

Overview of the Clinical Consult Case Review of adverse events following immunization: Clinical Immunization Safety Assessment (CISA) network 2004-2009

BACKGROUND

In 2004 the Clinical Consult Case Review (CCCR) working group was formed within the CDC-funded Clinical Immunization Safety Assessment (CISA) Network to review individual cases of adverse events following immunizations (AEFI).

METHODS

Cases were referred by practitioners, health departments, or CDC employees. Vaccine Adverse Event Reporting System (VAERS) searches and literature reviews for similar cases were performed prior to review. After CCCR discussion, AEFI were assessed for a causal relationship with vaccination and recommendations regarding future immunizations were relayed back to the referring physicians. In 2010, surveys were sent to referring physicians to determine the utility and effectiveness of the CCCR service.

RESULTS

CISA investigators reviewed 76 cases during 68 conference calls between April 2004 and December 2009. Almost half of the cases (35/76) were neurological in nature. Similar AEFI for the specific vaccines received were discovered for 63 cases through VAERS searches and for 38 cases through PubMed searches. Causality assessment using the modified WHO criteria resulted in classifying 3 cases as definitely related to vaccine administration, 12 as probably related, 16 as possibly related, 18 as unlikely related, 10 as unrelated, and 17 had insufficient information to assign causality. The physician satisfaction survey was returned by 30 (57.7%) of those surveyed and a majority of respondents (93.3%) felt that the CCCR service was useful.

CONCLUSIONS

The CCCR provides advice about AEFI to practitioners, assigns potential causality, and contributes to an improved understanding of adverse health events following immunizations.

Quadrivalent human papillomavirus (HPV) types 6, 11, 16, 18 vaccine: for the prevention of genital warts in males

The quadrivalent HPV types 6, 11, 16, 18 vaccine (Gardasil®) is a recombinant vaccine comprising purified virus-like particles derived from the L1 capsid proteins of HPV types 6, 11, 16 and 18. The vaccine was highly immunogenic. Geometric mean titres (GMTs) and seroconversion rates for all four HPV types at month 7 in males aged 10-15 years were noninferior to those in females aged 16-23 years, and those in males aged 9-15 years were noninferior to those in females aged 9-15 years. In addition, GMTs and seroconversion rates in males aged 16-26 years receiving the vaccine were higher than those receiving amorphous aluminium hydroxyphosphate sulfate adjuvant (AAHS) control. The quadrivalent HPV vaccine was significantly more effective than AAHS control at decreasing the incidence of HPV 6-, 11-, 16- or 18-related external genital lesions (primary endpoint) in a randomized, double-blind, placebo-controlled, multicentre study in males aged 16-26 years. The most common clinical endpoint was HPV 6- and 11-related condyloma; efficacy was robust against these lesions. The vaccine is also expected to be protective against genital warts in males aged 9-15 years, as the immune response in males of this age group was noninferior to that in males aged 16-26 years. The quadrivalent HPV vaccine was generally well tolerated in males aged 9-26 years. The most common adverse events reported were injection-site related, and most of these were of mild to moderate severity.

Global challenges of implementing human papillomavirus vaccines

Human Papillomavirus vaccines are widely hailed as a sweeping pharmaceutical innovation for the universal benefit of all women. The implementation of the vaccines, however, is far from universal or equitable. Socio-economically marginalized women in emerging and developing, and many advanced economies alike, suffer a disproportionately large burden of cervical cancer. Despite the marketing of Human Papillomavirus vaccines as the solution to cervical cancer, the market authorization (licensing) of the vaccines has not translated into universal equitable access. Vaccine implementation for vulnerable girls and women faces multiple barriers that include high vaccine costs, inadequate delivery infrastructure, and lack of community engagement to generate awareness about cervical cancer and early screening tools. For Human Papillomavirus vaccines to work as a public health solution, the quality-assured delivery of cheaper vaccines must be integrated with strengthened capacity for community-based health education and screening.

An overview on the field of micro- and nanotechnologies for synthetic Peptide-based vaccines

The development of synthetic peptide-based vaccines has many advantages in comparison with vaccines based on live attenuated organisms, inactivated or killed organism, or toxins. Peptide-based vaccines cannot revert to a virulent form, allow a better conservation, and are produced more easily and safely. However, they generate a weaker immune response than other vaccines, and the inclusion of adjuvants and/or the use of vaccine delivery systems is almost always needed. Among vaccine delivery systems, micro- and nanoparticulated ones are attractive, because their particulate nature can increase cross-presentation of the peptide. In addition, they can be passively or actively targeted to antigen presenting cells. Furthermore, particulate adjuvants are able to directly activate innate immune system in vivo. Here, we summarize micro- and nanoparticulated vaccine delivery systems used in the field of synthetic peptide-based vaccines as well as strategies to increase their immunogenicity.

Quadrivalent human papillomavirus (types 6, 11, 16, 18) recombinant vaccine (Gardasil®): a review of its use in the prevention of premalignant genital lesions, genital cancer and genital warts in women

Quadrivalent human papilloma virus (HPV) [types 6, 11, 16, 18] recombinant vaccine (Gardasil®; Silgard®) is composed of virus-like particles (VLPs) formed by self-assembly of recombinant L1 capsid protein from each of HPV types 6, 11, 16 and 18. The VLPs are noninfectious, containing no DNA, and are highly immunogenic, inducing high levels of neutralizing antibodies against the particular HPV types when administered to animals or humans. Quadrivalent HPV vaccine is indicated for use from the age of 9 years for the prevention of premalignant genital lesions (cervical, vulvar and vaginal), cervical cancer and external genital warts (condyloma acuminata) causally related to certain oncogenic or specific HPV types. In placebo-controlled clinical trials, quadrivalent HPV vaccine administered as three doses over 6 months provided high-level protection against infection or disease caused by the vaccine HPV types over 2-4 years of follow-up in females aged 15-45 years who were naive to the vaccine HPV types. A degree of cross-protection against certain other non-vaccine high-risk HPV types was also observed. The vaccine is not effective against current infection with a vaccine HPV type. Girls or women with current infection with one or more of the vaccine HPV types gained protection from infection or disease caused by the remaining vaccine HPV types and they were also protected against reinfection with the same HPV type after clearance of an infection caused by a vaccine HPV type. High seroconversion rates and high levels of anti-HPV antibodies were observed in all vaccinated individuals of all age ranges from 9 to 45 years. No correlation was found between antibody levels and protective efficacy of the vaccine. Rechallenge with quadrivalent HPV vaccine produced a potent anamnestic humoral immune response. The vaccine is generally well tolerated and is projected to be cost effective in most pharmacoeconomic models. Therefore, quadrivalent HPV vaccine offers an effective means, in combination with screening programmes, to substantially reduce the burden of HPV-related precancerous lesions and cancer, particularly cervical cancer, as well as anogenital warts.

Incident HPV 51 Infection After Prophylactic Quadrivalent Human Papillomavirus (Types 6, 11, 16, and 18) L1 Virus-Like Particle Vaccine Gardasil/Silgard

We report the case of a 19-year-old woman who received a complete vaccine program by Gardasil. After one year, Greiner HPV test revealed HPV51 positivity. This case report highlights the limits of the vaccine, and the need to have a clinical follow up of patients despite the vaccination program.