Safety of human papillomavirus vaccines in healthy young women: a meta-analysis of 24 controlled studies

Impact of industry sponsorship on the quality of systematic reviews of vaccines: a cross-sectional analysis of studies published from 2016 to 2019

BACKGROUND

Systematic reviews (SRs) provide the highest level of evidence and inform evidence-based decision making in health care. Earlier studies found association with industry to be negatively associated with methodological quality of SRs. However, this has not been investigated in SRs on vaccines.

METHODS

We performed a systematic literature search using MEDLINE and EMBASE in March 2020. The results were restricted to those published between 2016 and 2019 with no language restrictions. Study characteristics were extracted by one person and checked by an experienced reviewer. The methodological quality of the SRs was assessed with the AMSTAR 2 tool by multiple reviewers after a calibration exercise was performed. A summary score for each SR was calculated. The Mann-Whitney U test and Fisher's exact test were performed to compare both groups.

RESULTS

Out of 185 SRs that met all inclusion criteria, 27 SRs were industry funded. Those were matched with 30 non-industry funded SRs resulting in a total sample size of 57. The mean AMSTAR 2 summary score across all SRs was 0.49. Overall, the median AMSTAR 2 summary score was higher for the non-industry funded SRs than for the industry-funded SRs (0.62 vs. 0.36; p < .00001). Lower ratings for industry funded SRs were consistent across all but one AMSTAR 2 item, though significantly lower only for three specific items.

CONCLUSION

The methodological quality of SRs in vaccination is comparable to SRs in other fields, while it is still suboptimal. We are not able to provide a satisfactory explanation why industry funded SRs had a lower methodological quality than non-industry funded SRs over recent years. Industry funding is an important indicator of methodological quality for vaccine SRs and should be carefully considered when appraising SR quality.

A nationwide epidemiological survey of adolescent patients with diverse symptoms similar to those following human papillomavirus vaccination: background prevalence and incidence for considering vaccine safety in Japan

BACKGROUND

Since June 2013, Japan has suspended proactive recommendation of human papillomavirus (HPV) vaccination due to self-reported diverse symptoms, including pain and motor dysfunction, as possible serious adverse events following immunization. Although these symptoms may be seen in adolescents without HPV vaccination, their frequency taking into account disease severity has not been examined.

METHODS

A two-stage, descriptive, nationwide epidemiological survey was conducted in 2016 with a 6-month targeted period from July 1 to December 31, 2015 to estimate the prevalence and incidence of diverse symptoms among Japanese adolescents without HPV vaccination. Participants were 11,037 medical departments in hospitals selected nationwide by stratified random sampling. Eligible patients had to satisfy four criteria: (1) aged 12-18 years upon visiting hospital; (2) having at least one of four symptoms/disorders (pain or sensory dysfunction, motor dysfunction, autonomic dysfunction, or cognitive impairment); (3) symptoms/disorders persisting for at least three months; and (4) both criteria (2) and (3) influence attendance at school or work. We further extracted patients with diverse symptoms similar to those after HPV vaccination while considering opinions of doctors in charge.

RESULTS

Estimated 6-month period prevalence of diverse symptoms among girls aged 12-18 years without HPV vaccination was 20.2 per 100,000. Annual incidence was estimated to be 7.3 per 100,000.

CONCLUSION

Adolescent Japanese girls without HPV vaccination also visited hospitals with diverse symptoms similar to those following HPV vaccination. Our findings predicted the medical demands for diverse symptoms that are temporally associated with but not caused by vaccination of Japanese adolescents.

The comparative safety of human papillomavirus vaccines: A Bayesian network meta-analysis

BACKGROUND AND AIMS

The safety of human papillomavirus (HPV) vaccines, one of the major challenges to public vaccination, has been controversial. This study assessed the adverse reactions of various HPV vaccines, including bivalent HPV (2vHPV), quadrivalent HPV (4vHPV), and 9-valent HPV (9vHPV) vaccines.

METHODS

PubMed, Embase, and Central databases were searched for randomized controlled trials (RCTs) on the comparative safety of HPV vaccines. A network meta-analysis was performed based on the Bayesian framework random-effects model.

RESULTS

This study included 23 RCTs. Analysis across these reports indicated that the 2vHPV vaccine was associated with significantly more systemic adverse events than the 4vHPV vaccine (risk ratio [RR]: 1.28, 95% credible interval [CrI]: 1.14-1.44), 9vHPV vaccine (RR: 1.25, 95% CrI: 1.06-1.49), and placebo (RR: 1.31, 95% CrI: 1.18-1.46). However, there were no statistically significant differences in serious adverse events between the vaccinated and placebo groups. For injection-site adverse events, there were substantial inconsistencies between the direct and indirect effects; therefore, the analysis results of the safety were presented only for systemic and serious adverse events.

CONCLUSIONS

The 2vHPV vaccine resulted in more systemic adverse events than other vaccines and placebo. No significant differences in serious adverse events were observed. Further studies are needed to obtain more information regarding the safety of HPV vaccines.

Adverse events associated with human papillomavirus vaccines: a protocol for systematic review with network meta-analysis incorporating all randomised controlled trials comparing with placebo, adjuvants and other vaccines

INTRODUCTION

Adverse events following the injection (AEFIs) of human papillomavirus vaccine (HPVv) among female adolescents are still a major public health concern.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension statement for systematic reviews incorporating network meta-analyses, all prospective randomised trials will be included. The primary outcome for adverse events is topical pain during the observation period.We will mainly search 17 electronic databases from January 2000 through September 2019 with suitable Medical Subject Headings and text words for PubMed. Two reviewers will independently check the reports at the title/abstract level and identify potentially applicable studies. Then we will obtain their full texts and decide whether to include them based on the same eligible criteria.We will compare HPVv with placebo, HPVv with adjuvant and HPVv with other vaccines. Interstudy heterogeneity, publication biases or small study effects will be evaluated using conventional meta-analysis methods. The consistency of the network will be checked using tests for local and global inconsistency and the side-splitting method. To address the heterogeneity of treatment effects among the studies, we will use the multivariable random effect model.

ETHICS AND DISSEMINATION

This pairwise or network meta-analysis does not require ethics approval. The data used here are not individual nor private. We will be able to determine which component of the vaccine induces adverse events, especially topical pain. This systematic review with network meta-analysis will provide valid answers regarding AEFIs for HPVv.

PROSPERO REGISTRATION NUMBER

CRD42018109265.

Post Marketing Surveillance Study of 2nd Dose Quadrivalent Human Papilloma Virus Vaccine in Elementary School Children in Jakarta, Indonesia: Safety Result and Implementation of School-Based HPV Immunization Program

Objective: Quadrivalent human papillomavirus (QHPV) vaccine has been advised for routine vaccination of pre-adolescent girls globally, and a two-dose QHPV vaccination schedule has been introduced in Indonesia to vaccinate 5th and 6th grade elementary school female students. This post-marketing surveillance study evaluated the possible adverse events following immunization with the two-dose QHPV vaccine in Indonesia. Methods: Girls studying in grade 6 of five designated elementary schools in Jakarta, receiving their 2nd dose of QHPV vaccine and provided informed consent (represented by their parents), were included in the study. Students who had received other immunizations either simultaneously or <1 month ago were excluded. Local and systemic reactions noted at 30 min, and 72 h to 28th day, after the immunization were recorded using a Children Symptom Dairy Card/Kartu Harian Anak Sekolah (KHAS/ Student Daily Card). Results: A total of 500 students from 20 schools were included. No serious adverse events were reported during the study period. Fever (systemic reaction) of mild intensity was noted in 1.6 % (n=8) of participants, which subsided after day 6. Local reactions such as pain, redness and swelling were noted in 59.6% (n=295), 23.6% (n=118), and 17.2% (n=86) of participants, respectively. These resolved without any intervention in majority of the cases after day 5. Conclusion: These results along with the safety data from the pre-licensure clinical trials confirm the favorable safety profile of QHPV vaccine in pre-adolescent girls. The school-based two-dose QHPV immunization program in Indonesia is a safe and effective strategy for optimizing HPV vaccine coverage among pre-adolescent girls.

HPV vaccines and lupus: current approaches towards preventing adverse immune cross-reactivity

INTRODUCTION

If not properly treated, human papillomavirus (HPV) infection may evolve from a common sexually transmitted disease to genital warts and cervical cancer. Various prophylactic HPV vaccines (HPVv), approved to reduce the incidence of the infection, have been found to be effective and safe; however, accounts of post-vaccination autoimmune phenomena, including systemic lupus erythematosus (SLE), have been reported in genetically susceptible individuals.

AREAS COVERED

Infectious agents play a role in breaking the immunologic tolerance to self-antigens, resulting in autoimmune events. There is molecular evidence supporting the involvement of HPV in SLE, with a high prevalence of L1 HPV peptide homology to proteins being associated with SLE. Therefore, approaches in vaccine preparations aiming to prevent adverse immune cross-reactivity are sought. Performing a broad search of the literature, we review the association between SLE, HPV, and HPVv, with a focus on the mechanisms of molecular mimicry and cross-reactivity, and the approaches currently being elaborated towards preventing such phenomena.

EXPERT COMMENTARY

The advantages of using low-similarity peptide antigens may be two-fold, abolishing the risk of cross-reactivity and eliminating the vaccine adjuvantation procedure. Vaccines based on pathogen unique sequences would provide effective vaccine preparation while curbing the risk for the human host.

Addressing Human Papillomavirus Prevention During Pediatric Acute Sexual Assault Care

BACKGROUND/OBJECTIVES

Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States. Pediatric sexual assault (SA) victims are a special population eligible for HPV vaccination at the age of 9 years. National clinical practice guidelines advise clinicians to address HPV during emergency department (ED)-based SA care and at follow-up. At our institution, addressing HPV among suspected SA victims was highly variable, and HPV counseling was subsequently recommended on an ED-based acute SA clinical pathway as standard care. The aim of this study was to determine the proportion of age-eligible SA victims who received HPV counseling, determine victim characteristics associated with addressing HPV during SA care, and identify barriers to addressing HPV in the ED.

METHODS

This study used a retrospective chart review of 448 pediatric SA victims presenting to the ED for acute postassault care.

RESULTS

HPV was discussed in 10 of 56 (18%) and 37 of 49 (76%) cases in the control versus intervention groups, respectively. To verify vaccination status, caregiver recall was relied upon for 32 of 56 patients in the control group (57%) and 24 of 49 patients in the intervention group (48.9%). Factors associated with failure to discuss HPV during postassault care were younger age at encounter (OR = 0.78, 95% CI [0.67, 0.90], p < 0.001), verbal report of vaccination status verification (OR = 2.98, 95% CI [1.51, 6.01]), and male gender of the victim (OR = 3.35, 95% CI [1.20, 11.94]).

CONCLUSIONS

Significant barriers to addressing HPV in the ED setting exist, most significantly reliance on caregiver recall to guide vaccination administration, raising concern for overvaccination and undervaccination.