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Effector and Memory Immune Responses to HPV Vaccination in Vietnamese Women Post Virus Exposure

Phase 2
Not yet recruiting
Conditions
HPV Infection
Cervical Cancer
Anogenital Cancer
Anogenital Warts
Interventions
Registration Number
NCT06681636
Lead Sponsor
National Institute of Hygiene and Epidemiology, Vietnam
Brief Summary

A Study to evaluate if the 3 dose extended schedule (0-6-18 months) for the HPV vaccine Gardasil-9 provide similar immune responses and short term protection against HPV infection compared to the regular 3 dose schedule (0-2-6 months) in high risk women in Vietnam

Detailed Description

Primary objective:

To determine whether antibody geometric mean titer (GMT) to vaccine type HPV16 and HPV18 at 7 months (m) are non-inferior between female sex workers (FSW) aged 18-26 years who received the standard (0, 2m, 6m) and those received the extended 3-dose (at 0, 6m and 18m) 9vHPV schedule and age-matched non-FSW who received an extended 3-dose (at 0, 6m and 18m) 9vHPV schedule. This extended 3-dose schedule is in line with the recommended schedule by the vaccine manufacturer in Vietnam.

Secondary objectives:

1. To compare antibody GMT at 2m, 7m, 18m and 19m between FSW who are HPV DNA+/seropositive with FSW who are HPV DNA-/seronegative at baseline.

2. To compare antibody GMT at 18m and 19m between FSW and non-FSW.

3. To determine cellular immune responses to HPV16 and 18 at baseline, 2m, 7m, 18m and 19m.

4. To measure incidence and 6m/12m/18m persistent HPV infection.

Primary hypothesis:

HPV antibody GMT to HPV16 and 18 in FSW is non-inferior to those of young women of the same age group (non-FSW) at 7m.

Secondary hypothesis:

1. HPV antibody GMT are similar at 2m, 7m, 18m and 19m between FSW who are HPV DNA+/seropositive and HPV DNA-/seronegative at month 0.

2. HPV antibody GMT are similar at 18m and 19m between FSW and non-FSW who received the extended schedule.

3. Cellular immune responses to HPV16 and 18 are similar between FSW and non-FSW at 2m, 7m, 18m and 19m who received the extended schedule.

4. No new vaccine-type HPV infection in FSW and non-FSW in all groups at 6m, 12m, 18m.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
Female
Target Recruitment
300
Inclusion Criteria
  • Is between the reporting ages of 18-26 years at the time of recruitment.
  • Engage in commercial sex in the last 6m (for FSW group) or have engaged in sexual activity (non-FSWs)
  • Willing and able to give written informed consent.
  • Willing to complete the follow-up requirements of the study.

Exclusion criteria

Participants meeting any of the following criteria will be excluded from the trial:

  • Pregnant or possibly pregnant
  • Has received any HPV vaccine previously
  • Has an axillary temperate greater than 38°C
  • Known allergies to any vaccine component
  • incapacity to provide consent
  • Currently receiving immunosuppressive medication or anti-cancer chemotherapy.
  • Known HIV infection.
  • Known Congenital immune deficiency syndrome.
Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Group 1 FSWHuman papillomavirus 9-valent vaccine, Recombinant100 FSWs aged 18-26 years receiving 3 doses of Gardasil-9 vaccine at 0-6-18 months
Group 3 FSWHuman papillomavirus 9-valent vaccine, Recombinant100 FSW aged 18-26 years receiving 3 doses of Gardasil-9 vaccine at 0-2-6 months
Group 2 non-FSWHuman papillomavirus 9-valent vaccine, Recombinant100 non-FSW aged 18-26 years receiving 3 doses of Gardasil-9 vaccine at 0-6-18 months
Primary Outcome Measures
NameTimeMethod
Comparison between antibody responses after the 3rd dose ofregular vaccine schedules among FSW and after the 2nd dose of the extended schedule7 months from the first doses

geometric mean titer (GMT) ratios and 95% confidence intervals (CI) of HPV- specific antibody responses to HPV16 and HPV18 at 7m between FSWs aged 18-26 years who received either the standard (0, 2m, 6m) or extended 3-dose (at 0, 6m and 18m) 3-dose 9vHPV schedule and age-matched non-FSWs who received the extended 3-dose 9vHPV schedule (at 0, 6m and 18m).

Secondary Outcome Measures
NameTimeMethod
Comparison of antibody responses after each doses among FSW according to HPV infection status pre-vaccination19 months after the 1st doses

Antibody GMT at 2m, 7m, 18m and 19m between FSW who are HPV DNA+/seropositive with FSW who are HPV DNA-/seronegative at baseline.

Comparison of antibody response after 3 doses of extended schedule between FSW and non-FSW19 month after the first doses

Antibody GMT at 18m and 19m between FSW and non-FSW.

Celular response after each vaccine dose19 months after the 1st dose

Proportion of HPV16 and 18-specific B/T cells at baseline, 2m, 7m, 18m and 19m.

HPV persistent during 19 month or more among vaccinesat least 19 months after the first dose

4. Incidence (detection of the specific-type HPV DNA at least once during the follow-up period) and persistent HPV infection (defined as detection of the same HPV type in at least 2 samples not interrupted by negative sample during the follow-up period).

Trial Locations

Locations (3)

Murdoch Children Research Institute

🇦🇺

Parkville, Victoria, Australia

Center for Supporting Community Development Initiatives SCDI-Vietnam

🇻🇳

Hai Phong, Vietnam

Hai Phong Center for Disease Control

🇻🇳

Hai Phong, Vietnam

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