Publications by authors named "Alfred Saah"

Article Synopsis
  • The study examined the incidence of anogenital HPV infections in 295 men who have sex with men (MSM) and 1,576 heterosexual men (HM) aged 16-27 years participating in a global HPV vaccine trial.
  • Results showed that MSM had significantly higher incidence rates of persistent HPV infections at various anatomical sites compared to heterosexual men, particularly at anal sites.
  • The findings suggest that gender-neutral HPV vaccination could reduce infections in males, improve overall public health protection, and lessen the disease burden associated with HPV.
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Individuals with human papillomavirus (HPV)-related disease remain at risk for subsequent HPV infection and related disease after treatment of specific lesions. Prophylactic HPV vaccines have shown benefits in preventing subsequent HPV-related disease when administered before or soon after treatment. Based on our understanding of the HPV life cycle and vaccine mechanism of action, prophylactic HPV vaccination is not expected to clear active persistent HPV infection or unresected HPV-associated dysplastic tissue remaining after surgery.

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Introduction: Human papillomavirus (HPV) infection, which poses significant disease burden, is decreasing following implementation of vaccination programs. Synthesized evidence on HPV vaccine real-world benefit was published in 2016. However, long-term impact of vaccination, and how vaccination programs influence infection rates and disease outcomes, requires further examination.

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Among women aged 27-45 years, the quadrivalent human papillomavirus (qHPV; HPV6/11/16/18) vaccine was generally well tolerated, efficacious, and immunogenic in the placebo-controlled FUTURE III study (NCT00090220; n = 3253). The qHPV vaccine was also generally well tolerated and highly immunogenic in men aged 27-45 years who participated in the single-cohort mid-adult male (MAM) study (NCT01432574; n = 150). Here, we report results of a long-term follow up (LTFU) extension of FUTURE III with up to 10 years follow-up.

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Background: Estimates of the humoral immune response to incident human papillomavirus (HPV) infections are limited.

Methods: In this post hoc analysis of 3875 women aged 16-23 years from a 4-valent HPV vaccine trial (NCT00092482), HPV seroprevalence on day 1 was measured with a 9-valent HPV (HPV 6/11/16/18/31/33/45/52/58) competitive Luminex immunoassay and compared with cervical/external genital HPV detection by polymerase chain reaction. In the control group, among women who were HPV DNA‒negative on day 1, seroconversion following initial HPV detection was estimated using Kaplan-Meier methods.

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Although no human papillomavirus (HPV) vaccine is indicated for single-dose administration, some observational evidence suggests that a 1-dose regimen might reduce HPV infection risk to that achieved with 2 doses. This study estimated the potential health and economic outcomes associated with switching from a 2-dose HPV vaccination program for girls and boys aged 13-14 years to an off-label 9-valent (9vHPV), 1-dose regimen, accounting for the uncertainty of the effectiveness and durability of a single dose. A dynamic HPV transmission infection and disease model was adapted to the United Kingdom and included a probabilistic sensitivity analysis using estimated distributions for duration of protection of 1-dose and degree of protection of 1 relative to 2 doses.

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Background: The quadrivalent human papillomavirus (HPV) vaccine was shown to prevent infections and lesions related to HPV6, 11, 16, and 18 in a randomised, placebo-controlled study in men aged 16-26 years. We assessed the incidences of external genital warts related to HPV6 or 11, and external genital lesions and anal dysplasia related to HPV6, 11, 16, or 18, over 10 years of follow-up.

Methods: The 3-year base study was an international, multicentre, double-blind, randomised, placebo-controlled trial done at 71 sites in 18 countries.

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Background: In men, the incidence of human papillomavirus (HPV)-related cancer is rising, but data regarding male HPV infection and seroprevalence are available from only a few countries.

Methods: This analysis of a global HPV vaccine trial evaluated baseline data from 1399 human immunodeficiency virus-negative heterosexual men (HM) and men who have sex with men (MSM). Key objectives included assessment of HPV prevalence and risk factors for seropositivity to 9-valent HPV (9vHPV) vaccine types (6, 11, 16, 18, 31, 33, 45, 52, and 58), and concordance between seropositivity and prevalent HPV type.

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Background: The extent of cross-protection provided by currently licensed bivalent and quadrivalent HPV vaccines versus direct protection against HPV 31-, 33-, 45-, 52-, and 58-related disease is debated. A systematic literature review was conducted to establish the duration and magnitude of cross-protection in interventional and observational studies.

Methods: PubMed and Embase databases were searched to identify randomized controlled trials (RCT) and observational studies published between 2008 and 2019 reporting on efficacy and effectiveness of HPV vaccines in women against non-vaccine types 31, 33, 45, 52, 58, and 6 and 11 (non-bivalent types).

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Introduction: Studies on the cross-protective effect of HPV bivalent and quadrivalent vaccines demonstrated inconsistent findings against additional HPV types covered by the nonavalent vaccine. The objective of this study was to conduct a systematic literature review to assess the consistency and durability of the cross-protective neutralizing antibody immune responses of the currently licensed bivalent and quadrivalent vaccines to non-vaccine HPV types targeted by the nonavalent vaccine (HPV 6, 11, 31, 33, 45, 52, and 58).

Methods: PubMed and EMBASE databases were searched from 2008 to 2019 to identify studies reporting antibody/immune response after vaccination with either the bivalent, quadrivalent, or nonavalent vaccine.

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Article Synopsis
  • A study evaluated the HPV antibody responses in boys and girls (ages 9-14) who received a 2-dose regimen of the 9-valent HPV vaccine and found their responses comparable to those in young women (ages 16-26) who received a 3-dose regimen, assessed 4 weeks post-vaccination.
  • The study involved different dosing schedules for the vaccines among participants and measured HPV antibody levels over 36 months using advanced immunoassay techniques.
  • Results indicated that antibody levels were highest one month after vaccination, decreased sharply in the following year, but remained sufficient for protection, showing that a 2-dose regimen can ensure long-lasting immunity for at least 2 to 2.5 years.
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Background: The quadrivalent human papillomavirus (qHPV) vaccine prevented vaccine HPV type-related infection and disease in young women in the 4-year FUTURE II efficacy study (NCT00092534). We report long-term effectiveness and immunogenicity at the end of 14 years of follow-up after enrollment in FUTURE II.

Methods: Young women (16-23 years of age) from Denmark, Iceland, Norway, and Sweden who received three qHPV vaccine doses during the randomized, double-blind, placebo-controlled FUTURE II base study were followed for effectiveness for an additional ≥10 years through national registries.

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Objectives: The natural history of human papillomavirus (HPV) infection has been studied extensively in young women; this study investigated HPV infection in adult women.

Methods: Data from 3817 women aged 24-45 years in a global trial of the 4-valent HPV (6/11/16/18) vaccine were used to calculate prevalence of anogenital infections containing 9-valent (9v) HPV vaccine types (6/11/16/18/31/33/45/52/58) and five non-vaccine types (35/39/51/56/59). Incidence of infections and persistent infections was estimated for 989 placebo recipients naive to all 14 HPV types at baseline.

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Post-marketing studies are commonly performed to follow-up on the safety and effectiveness of a drug or vaccine after approval has been obtained. These post-marketing studies may involve the collection of real-world data from registries and clinical biobanks in order to obtain real-world evidence. As this approach can monitor the effects of pharmaceutical products over decades, it is particularly necessary for the development of safe and effective vaccines.

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Background: A quadrivalent human papillomavirus (qHPV) vaccine (HPV6/11/16/18) has demonstrated efficacy and acceptable safety in international studies. However, these studies did not include participants from mainland China, which has a substantial burden of HPV-related disease. This is the first safety report with a follow-up period of up to 90 months from a randomized, double-blind, placebo-controlled trial of qHPV vaccine in Chinese women 20-45 years of age.

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Background: A quadrivalent human papillomavirus vaccine (qHPV; HPV6/11/16/18) has demonstrated efficacy and effectiveness worldwide. We report qHPV vaccine efficacy for up to 6.5 years after first administration among Chinese women 20-45 years of age.

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Objectives: People living with HIV have increased Human Papillomavirus (HPV) related lesions and malignancies. We describe HPV DNA recovered from the cervix and anal canal, explore the effect of vaccination on HPV detection, and examine the durability of vaccine titers in women living with HIV-1 who were vaccinated with the quadrivalent HPV vaccine.

Methods: AIDS Clinical Trials Group A5240 was a prospective study of the quadrivalent HPV (qHPV) vaccine in 315 HIV-1 infected women in three CD4 strata (A: >350, B; 201-350, C: ≤200 cells/mm).

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Objective: To estimate the proportion of vulvar and vaginal low-grade and high-grade squamous intraepithelial lesions (LSILs and HSILs) in females 15-26 years of age attributable to 14 human papillomavirus (HPV) genotypes (6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59).

Methods: A post hoc analysis of prospectively diagnosed vulvar and vaginal LSILs and HSILs among females 15-26 years of age enrolled in the placebo arms of two phase 3, randomized HPV vaccine trials assessed 14 prespecified HPV genotypes associated with cervical cancers or anogenital warts using a type-specific multiplex polymerase chain reaction assay. The frequency of lesions associated with specific HPV genotypes was estimated by proportional and other attribution methods.

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Background: Adults living with human immunodeficiency virus (HIV) are at increased risk for anal and oropharyngeal cancer caused by human papillomavirus (HPV). The efficacy of HPV vaccines in this population is unknown.

Methods: In this phase 3, double-blind, randomized, controlled trial, we assigned HIV-infected adults aged ≥27 years to the quadrivalent HPV (types 6, 11, 16, 18) vaccine or placebo (1:1) stratified by sex and presence of anal high-grade squamous intraepithelial lesions on biopsy (bHSIL).

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Background: The quadrivalent human papillomavirus (HPV) vaccine (qHPV; types 6, 11, 16, 18) is indicated for men and women aged 9 to 26 years to prevent HPV associated anogenital high-grade squamous intraepithelial lesions (HSIL) and cancer. ACTG 5298 was a randomized placebo controlled Phase 3 study in human immunodeficiency virus (HIV)-infected men who have sex with men, and women of qHPV to prevent persistent anal HPV infection. Baseline data are presented here.

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Objectives: We describe the final 10-year data for the long-term follow-up study of the 4-valent human papillomavirus (4vHPV) vaccine in preadolescents and adolescents.

Methods: In the base study (V501-018), 1661 sexually inactive boys and girls received the 4vHPV vaccine (early vaccination group [EVG], managed for 9.9 years) or a placebo at day 1, month 2, and month 6.

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Background: We estimated the proportion of cervical intraepithelial neoplasia (CIN) cases attributed to 14 HPV types, including quadrivalent (qHPV) (6/11/16/18) and 9-valent (9vHPV) (6/11/16/18/31/33/45/52/58) vaccine types, by region METHODS: Women ages 15-26 and 24-45 years from 5 regions were enrolled in qHPV vaccine clinical trials. Among 10,706 women (placebo arms), 1539 CIN1, 945 CIN2/3, and 24 adenocarcinoma in situ (AIS) cases were diagnosed by pathology panel consensus.

Results: Predominant HPV types were 16/51/52/56 (anogenital infection), 16/39/51/52/56 (CIN1), and 16/31/52/58 (CIN2/3).

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