Quadrivalent Human Papillomavirus Vaccine: Recommendations of the Advisory Committee on Immunization Practices (ACIP).
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These recommendations represent the first statement by the Advisory Committee on Immunization Practices (ACIP) on the use of a quadrivalent human papillomavirus (HPV) vaccine licensed by the U.S. Food and Drug Administration on June 8, 2006. This report summarizes the epidemiology of HPV and associated diseases, describes the licensed HPV vaccine, and provides recommendations for its use for vaccination among females aged 9-26 years in the United States. Genital HPV is the most common sexually transmitted infection in the United States; an estimated 6.2 million persons are newly infected every year. Although the majority of infections cause no clinical symptoms and are self-limited, persistent infection with oncogenic types can cause cervical cancer in women. HPV infection also is the cause of genital warts and is associated with other anogenital cancers. Cervical cancer rates have decreased in the United States because of widespread use of Papanicolaou testing, which can detect precancerous lesions of the cervix before they develop into cancer; nevertheless, during 2007, an estimated 11,100 new cases will be diagnosed and approximately 3,700 women will die from cervical cancer. In certain countries where cervical cancer screening is not routine, cervical cancer is a common cancer in women. The licensed HPV vaccine is composed of the HPV L1 protein, the major capsid protein of HPV. Expression of the L1 protein in yeast using recombinant DNA technology produces noninfectious virus-like particles (VLP) that resemble HPV virions. The quadrivalent HPV vaccine is a mixture of four HPV type-specific VLPs prepared from the L1 proteins of HPV 6, 11, 16, and 18 combined with an aluminum adjuvant. Clinical trials indicate that the vaccine has high efficacy in preventing persistent HPV infection, cervical cancer precursor lesions, vaginal and vulvar cancer precursor lesions, and genital warts caused by HPV types 6, 11, 16, or 18 among females who have not already been infected with the respective HPV type. No evidence exists of protection against disease caused by HPV types with which females are infected at the time of vaccination. However, females infected with one or more vaccine HPV types before vaccination would be protected against disease caused by the other vaccine HPV types. The vaccine is administered by intramuscular injection, and the recommended schedule is a 3-dose series with the second and third doses administered 2 and 6 months after the first dose. The recommended age for vaccination of females is 11-12 years. Vaccine can be administered as young as age 9 years. Catch-up vaccination is recommended for females aged 13--26 years who have not been previously vaccinated. Vaccination is not a substitute for routine cervical cancer screening, and vaccinated females should have cervical cancer screening as recommended. (+info)
Evidence of recombination within human alpha-papillomavirus.
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BACKGROUND: Human papillomavirus (HPV) has a causal role in cervical cancer with almost half a million new cases occurring each year. Presence of the carcinogenic HPV is necessary for the development of the invasive carcinoma of the genital tract. Therefore, persistent infection with carcinogenic HPV causes virtually all cervical cancers. Some aspects of the molecular evolution of this virus, as the putative importance of recombination in its evolutionary history, are an opened current question. In addition, recombination could also be a significant issue nowadays since the frequency of co-infection with more than one HPV type is not a rare event and, thus, new recombinant types could be currently being generated. RESULTS: We have used human alpha-PV sequences from the public database at Los Alamos National Laboratory to report evidence that recombination may exist in this virus. A model-based population genetic approach was used to infer the recombination signal from the HPV DNA sequences grouped attending to phylogenetic and epidemiological information, as well as to clinical manifestations. Our results agree with recently published ones that use a different methodology to detect recombination associated to the gene L2. In addition, we have detected significant recombination signal in the genes E6, E7, L2 and L1 at different groups, and importantly within the high-risk type HPV16. The method used has recently been shown to be one of the most powerful and reliable procedures to detect the recombination signal. CONCLUSION: We provide new support to the recent evidence of recombination in HPV. Additionally, we performed the recombination estimation assuming the best-fit model of nucleotide substitution and rate variation among sites, of the HPV DNA sequence sets. We found that the gene with recombination in most of the groups is L2 but the highest values were detected in L1 and E6. Gene E7 was recombinant only within the HPV16 type. The topic deserves further study because recombination is an important evolutionary mechanism that could have high impact both in pharmacogenomics (i.e. on the influence of genetic variation on the response to drugs) and for vaccine development. (+info)
Genomic instability of the host cell induced by the human papillomavirus replication machinery.
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Development of invasive cervical cancer upon infection by 'high-risk' human papillomavirus (HPV) in humans is a stepwise process in which some of the initially episomal 'high-risk' type of HPVs (HR-HPVs) integrate randomly into the host cell genome. We show that HPV replication proteins E1 and E2 are capable of inducing overamplification of the genomic locus where HPV origin has been integrated. Clonal analysis of the cells in which the replication from integrated HPV origin was induced showed excision, rearrangement and de novo integration of the HPV containing and flanking cellular sequences. These data suggest that papillomavirus replication machinery is capable of inducing genomic changes of the host cell that may facilitate the formation of the HPV-dependent cancer cell. (+info)
An in vitro selection scheme for oligonucleotide probes to discriminate between closely related DNA sequences.
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Using an in vitro selection, we have obtained oligonucleotide probes with high discriminatory power against multiple, similar nucleic acid sequences, which is often required in diagnostic applications for simultaneous testing of such sequences. We have tested this approach, referred to as iterative hybridizations, by selecting probes against six 22-nt-long sequence variants representing human papillomavirus, (HPV). We have obtained probes that efficiently discriminate between HPV types that differ by 3-7 nt. The probes were found effective to recognize HPV sequences of the type 6, 11, 16, 18 and a pair of type 31 and 33, either when immobilized on a solid support or in a reverse configuration, as well to discriminate HPV types from the clinical samples. This methodology can be extended to generate diagnostic kits that rely on nucleic acid hybridization between closely related sequences. In this approach, instead of adjusting hybridization conditions to the intended set of probe-target pairs, we 'adjust', through in vitro selection, the probes to the conditions we have chosen. Importantly, these conditions have to be 'relaxed', allowing the formation of a variety of not fully complementary complexes from which those that efficiently recognize and discriminate intended from non-intended targets can be readily selected. (+info)
A cross-sectional study of a prototype carcinogenic human papillomavirus E6/E7 messenger RNA assay for detection of cervical precancer and cancer.
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PURPOSE: To evaluate carcinogenic human papillomavirus (HPV) mRNA for E6 and E7 mRNA detection on clinical specimens to identify women with cervical precancer and cancer. EXPERIMENTAL DESIGN: We evaluated a prototype assay that collectively detects oncogenes E6/E7 mRNA for 14 carcinogenic HPV genotypes on a sample of liquid cytology specimens (n=531), masked to clinical data and to the presence of HPV genotypes detected by PGMY09/11 L1 consensus primer PCR assay. RESULTS: We found an increasing likelihood of testing positive for carcinogenic HPV E6/E7 mRNA with increasing severity of cytology (P(Trend) < 0.0001) and histology (P(Trend) < 0.0001), with 94% of cervical intraepithelial neoplasia grade 3 (CIN3) histology cases (46 of 49) and all five cancer cases testing positive for carcinogenic HPV E6/E7 mRNA. Overall, fewer specimens tested positive for carcinogenic HPV E6/E7 mRNA than for carcinogenic HPV DNA (P<0.0001, McNemar's chi(2) test), especially in women with +info)
Significance and possible causes of false-negative results of reflex human Papillomavirus infection testing.
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BACKGROUND: The objective of this study was to assess the rate and possible reasons for false-negative (FN) reflex human papillomavirus (HPV)-DNA tests. METHODS: The authors reviewed all ThinPrep cervical specimens that were submitted for reflex HPV-DNA testing using the Digene Hybrid Capture II (HC2) method from January 2002 to January 2004. Follow-up biopsies were reviewed. The results were considered HPV-FN if the HPV-DNA test was negative and the biopsy was positive for grade > or =2 cervical intraepithelial neoplasia (CIN2+), and the results were considered true positive (HPV-TP) if the HPV-DNA test was positive and the biopsy showed CIN2+. HPV-FN cases were compared with HPV-TP cases regarding the grade and extent of CIN, the number of abnormal cells on the original ThinPrep slide, and the presence of amplifiable, viral DNA on biopsy. RESULTS: In total, 1520 (66%) of 2309 patients who had diagnoses of atypical squamous cells of undetermined significance (ASCUS) were negative for HPV DNA and 789 patients of 2309 patients (34%) were positive for HPV DNA. Three hundred sixteen women (40%) who had a positive HPV-DNA test underwent a biopsy. Of those, 36 biopsies (11%) showed CIN2+ (HPV-TP), and 154 biopsies (66%) showed CIN1. Cervical tissue was available for review from 82 women who had negative HPV-DNA tests; of these, 6 tissue samples (7%) showed CIN2+ (HPV-FN), and 13 tissue samples (16%) showed CIN1. Therefore, in the total ASCUS population that was triaged with reflex HPV testing, there were at least 42 women who were diagnosed with CIN2+, for an estimated CIN2+ FN fraction of 14% (6 of 42 women). HPV-FN lesions were smaller (but the difference was not statistically significant) and shed significantly fewer abnormal cells than HPV-TP cases. Polymerase chain reaction testing for viral DNA in the biopsy was detected in 3 of 6 women who had HPV-FN results; none of those positive results demonstrated a viral type that was not included in the Digene probes. CONCLUSIONS: Although the rate of FN high-grade lesions was significantly higher than that reported in the ASCUS/Low-grade Squamous Intraepithelial Lesion Triage trial, most missed lesions were small and shed few abnormal cells. It was assumed that those lesions were either in early stages or in regressing stages, which made their clinical significance uncertain. (+info)
Comparison of the Digene Hybrid Capture 2 assay and Roche AMPLICOR and LINEAR ARRAY human papillomavirus (HPV) tests in detecting high-risk HPV genotypes in specimens from women with previous abnormal Pap smear results.
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The development of cervical cancer is strongly associated with the presence of persistent high-risk (HR) human papillomavirus (HPV) infection. Recently, the commercially manufactured PCR-based Roche AMPLICOR (AMP) and LINEAR ARRAY (LA) HPV tests have become available for HPV detection. However, knowledge of their clinical performance compared to the U.S. Food and Drug Administration-approved Hybrid Capture 2 (HC2) assay is limited. This study evaluated the concordance between the HC2, AMP, and LA tests in detecting HR-HPV among a cohort of 1,679 women with previous abnormal Pap smear results. Overall, 1,393 specimens (81.3%) generated concordant results for HR-HPV presence or absence by the three assays. The concordance levels were substantial between the HC2 and AMP tests (84.4%, kappa = 0.6419) and between the HC2 and LA tests (84.0%, kappa = 0.6341) and nearly perfect between the AMP and LA tests (97.8%, kappa = 0.9441). HR-HPV prevalence, as detected by the AMP or LA tests, was significantly higher among women with cytological or histological high-grade disease (CIN2 or greater) than that detected by HC2 (P < 0.0001). The AMP and LA tests exhibited greater sensitivity, but lower specificity, than HC2 for detecting HR-HPV among this cohort of women with underlying cervical abnormalities, particularly among subjects with histologically proven high-grade disease. Both PCR-based HPV tests may be valuable in the management of care for women with underlying cervical abnormalities, in predicting treatment success, and in studying the clearance or acquisition of new infections. (+info)
Quadrivalent vaccine against human papillomavirus to prevent high-grade cervical lesions.
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BACKGROUND: Human papillomavirus types 16 (HPV-16) and 18 (HPV-18) cause approximately 70% of cervical cancers worldwide. A phase 3 trial was conducted to evaluate a quadrivalent vaccine against HPV types 6, 11, 16, and 18 (HPV-6/11/16/18) for the prevention of high-grade cervical lesions associated with HPV-16 and HPV-18. METHODS: In this randomized, double-blind trial, we assigned 12,167 women between the ages of 15 and 26 years to receive three doses of either HPV-6/11/16/18 vaccine or placebo, administered at day 1, month 2, and month 6. The primary analysis was performed for a per-protocol susceptible population that included 5305 women in the vaccine group and 5260 in the placebo group who had no virologic evidence of infection with HPV-16 or HPV-18 through 1 month after the third dose (month 7). The primary composite end point was cervical intraepithelial neoplasia grade 2 or 3, adenocarcinoma in situ, or cervical cancer related to HPV-16 or HPV-18. RESULTS: Subjects were followed for an average of 3 years after receiving the first dose of vaccine or placebo. Vaccine efficacy for the prevention of the primary composite end point was 98% (95.89% confidence interval [CI], 86 to 100) in the per-protocol susceptible population and 44% (95% CI, 26 to 58) in an intention-to-treat population of all women who had undergone randomization (those with or without previous infection). The estimated vaccine efficacy against all high-grade cervical lesions, regardless of causal HPV type, in this intention-to-treat population was 17% (95% CI, 1 to 31). CONCLUSIONS: In young women who had not been previously infected with HPV-16 or HPV-18, those in the vaccine group had a significantly lower occurrence of high-grade cervical intraepithelial neoplasia related to HPV-16 or HPV-18 than did those in the placebo group. (ClinicalTrials.gov number, NCT00092534 [ClinicalTrials.gov].). (+info)