Immunogenicity of 9-valent HPV Vaccine

Study Overview
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Brief Summary
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Human papillomavirus (HPV) causes the most prevalent sexually transmitted infections in the world. The nonavalent HPV vaccine (9vHPV) provides protection against 9 high-risk HPV serotypes, responsible for causing approximately 90% of cervical and other HPV-related anogenital cancers, as well as 90% of genital warts. The risk of cancer is substantially increased among immunocompromised patients. Although studies have demonstrated seroprotection among children and adolescents, boys and girls, with the 9vHPV vaccine, the immunogenicity of this vaccine has been poorly explored in immunocompromised children and adolescents (including transplant patients, and those infected with human immunodeficiency virus (HIV)). Several factors, including the immunological consequences of vertically acquired infection, immunosuppressive therapies and age, could lead to an increased risk of infection in children and adolescents who are immunocompromised. Lower immunogenicity in these populations. These children may have a poor response to vaccines and therefore require additional doses. Markers such as CD4/CD8 or torque teno virus (TTV) replication could be linked to immunogenicity and thus serve as predictors of efficacy for routine clinical practice.

Official Title
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Immunogenicity of 9-valent HPV Vaccine in Immunocompromised Children and Adolescents

Conditions
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Human Papilloma Virus Infection

Intervention / Treatment
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* Biological: 9-valent HPV vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Children or adolescents 9 to <18 years of age Willing to sign consent/assent form If HIV positive, under ART and undetectable viral load and CD4 cell count >200/mm3 (at least 6 months) If the patient has received chemotherapy or is a SOT/HSCT recipient, referred for immunizations after adequate immune reconstitution according to routine clinical practice Exclusion Criteria: Previous history of warts and/or anal cancer. Previous immunization with any HPV vaccine. Age below 9. Patients who for any reason should not be included in the study according to the evaluation of the research team.

Ages Eligible for Study
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Minimum Age: 9 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Two groups of patients: Immunosuppressed Group: N=90 Immunosuppressed patients, consisting of HIV-infected children and adolescents, hematopoietic stem cell transplant (HSCT) recipients, solid organ transplant (SOT) recipients and post-chemotherapy patients (PCT) under follow-up at Hospital La Paz in Madrid Spain. Control Group: N=30 Healthy controls aged 9-14. Both groups receive the 9-valent HPV vaccine.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Immunosuppressed Group<br>N=90 Immunosuppressed patients, consisting of HIV-infected children and adolescents, hematopoietic stem cell transplant (HSCT) recipients, solid organ transplant (SOT) recipients and post-chemotherapy patients (PCT) under follow up at Hospital La Paz in Madrid Spain. 9-valent HPV vaccine: three-dose schedule: Months 0-2-6. | Biological: 9-valent HPV vaccine<br>* All participants will receive the immunization schedule according to guidelines: immunosuppressed patients will receive a three-dose schedule: 0.5 mL intramuscular injection of 9vHPV at entry plus an additional dose at month 2 and month 6. Healthy controls aged 9-14 years will receive a two-dose schedule: 0 and 6 months.<br>|
| Other: Control Group<br>N=30 Healthy controls aged 9-14 9-valent HPV vaccine: two-dose schedule: Months 0-6. | Biological: 9-valent HPV vaccine<br>* All participants will receive the immunization schedule according to guidelines: immunosuppressed patients will receive a three-dose schedule: 0.5 mL intramuscular injection of 9vHPV at entry plus an additional dose at month 2 and month 6. Healthy controls aged 9-14 years will receive a two-dose schedule: 0 and 6 months.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion of subjects from baseline to month 7 (determined by serum anti-HPV antibody titers) | Percentage of subjects seroconverting from baseline to month 7 | From baseline to month 7 | 
| Seroconversion of subjects from baseline to month 12 (determined by serum anti-HPV antibody titers) | Percentage of subjects maintaining antibody titers 12 months after immunization. | From baseline to month 12 | 
| Seroconversion of subjects from baseline to month 18 (determined by serum anti-HPV antibody titers) | Percentage of subjects maintaining antibody titers 18 months after immunization. | From baseline to month 18 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ratio of geometric mean serum antibody titers (GMTs) | GMTs from baseline to month 7 | From baseline to month 7 | 
| Delta of geometric mean serum antibody titers | Delta of geometric mean serum antibody titers from 1 to 12 months after immunization. | From 1 to 12 months | 
| Percentage of subjects seroconverting from baseline to month 7 | Percentage of subjects seroconverting from baseline to month 7 in each of the study populations. | From baseline to month 7 |