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Testing HPV Vaccine to Prevent Return of Precancerous Lesions in Patients Treated for High-Grade Abnormal Cell Changes Caused by HPV

Fast replyRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This study examines the prevention of disease recurrence in people who have been treated for high-grade squamous intraepithelial lesions, which are abnormal cell changes caused by human papillomavirus infection. These abnormal cells can occur in different areas of the body including the cervix, vagina, vulva, anus, or penis. The treatment being tested is Gardasil 9, a vaccine that protects against nine types of human papillomavirus. Some people in the study will receive the vaccine while others will receive placebo. The vaccine is given as an injection into the muscle.

The purpose of this study is to see if the human papillomavirus vaccine can help prevent these abnormal cells from coming back after treatment. The study will look at how long it takes for the abnormal cells to return in people who receive the vaccine compared to those who receive placebo. The vaccine is designed to work against specific types of human papillomavirus that are known to cause these cell changes.

During the study, people will receive three doses of either the vaccine or placebo over a period of time. They will then be followed for up to five years to check if the abnormal cells come back. The study will also look at whether the vaccine helps clear the human papillomavirus from the body, whether it prevents new abnormal cells from developing in other areas, and whether it reduces the risk of developing cancer related to human papillomavirus. Safety will be monitored throughout the study by tracking any unwanted effects that may occur.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial treatment and enrollment

    Your participation begins after you have received treatment for high-grade squamous intraepithelial lesions, which are abnormal cells caused by human papillomavirus. These lesions may be located on the cervix, vulva, vagina, anus, or penis.

    Before receiving any study medication, a pregnancy test will be performed if you are a woman of childbearing potential. The test must be negative within 24 hours before the first injection.

    You will be randomly assigned to receive either the Gardasil 9 vaccine or a placebo. A placebo is an injection that looks identical but contains no active vaccine. Neither you nor your doctor will know which one you receive during the study.

  2. Step 2

    First injection

    You will receive the first injection of either Gardasil 9 or placebo into your muscle, typically in the upper arm.

    The injection is a liquid suspension that will be administered by a healthcare professional.

    After the injection, you will be observed for any immediate reactions.

  3. Step 3

    Second injection

    You will return to receive the second injection into your muscle.

    The timing of this injection will follow the standard vaccination schedule as determined by the study protocol.

    The same type of injection (vaccine or placebo) that you received during the first visit will be administered.

  4. Step 4

    Third injection

    You will return to receive the third and final injection into your muscle.

    This completes the full course of injections.

    The same type of injection (vaccine or placebo) will be administered as in the previous visits.

  5. Step 5

    Regular monitoring visits during first two years

    You will attend regular follow-up visits to monitor your health and check for any return of abnormal cells at the site where you were originally treated.

    During these visits, examinations and biopsies may be performed if abnormal cells are suspected.

    Samples will be collected to test for the presence of human papillomavirus and to identify which specific types of the virus are present.

    You will be asked about any side effects or health problems you have experienced.

    Information about your sexual health will be collected at specific time points.

    If you are sexually active, you must use appropriate contraception methods throughout this period.

  6. Step 6

    Extended monitoring period from year two to year five

    You will continue to attend follow-up visits, though they may be less frequent than during the first two years.

    The same types of examinations and sample collections will be performed to monitor for any return of abnormal cells or development of cancer related to human papillomavirus.

    Information about your sexual health will be collected again at the end of this period.

    Any side effects or health problems will continue to be recorded.

    Your participation in the study will conclude at the end of the five-year follow-up period.

Who can join the trial?

9 criteria

  • You must be a woman, man, or transgender person between 18 and 55 years old
  • You must have a confirmed diagnosis through biopsy (a small tissue sample) showing HPV-related HSIL (a type of abnormal cell change caused by human papillomavirus) in areas such as the vulva, vagina, cervix, anus, or penis
  • Your general health condition must be good enough to care for yourself, rated as ECOG performance status of 1 or less (this means you are fully active or able to do light work)
  • If you are living with HIV (a virus that affects the immune system), you can participate if you are taking antiretroviral therapy (medications to control HIV) and your viral load (amount of virus in your blood) cannot be detected
  • If you are a woman who can become pregnant, you must have a negative pregnancy test within 24 hours before receiving the first vaccine
  • If you are sexually active, you must agree to use effective birth control methods during the study and until you receive the last vaccine dose
  • You must be able to understand the study, sign the consent form, and follow all study visits and procedures
  • You must have health insurance or be covered by a social security system
  • Your life expectancy (how long doctors expect you to live) must be greater than 5 years

Who cannot join the trial?

9 criteria

  • Pregnancy or breastfeeding: Women who are pregnant or nursing a baby cannot participate in this study.
  • Previous HPV vaccination: People who have already received the HPV vaccine (a vaccine that protects against human papilloma virus) cannot join this study.
  • Weakened immune system: People with conditions that weaken the body's ability to fight infections, such as HIV/AIDS (a virus that damages the immune system) or those taking medicines that suppress the immune system, cannot participate.
  • Cancer diagnosis: People who currently have cancer or have had cancer in the past related to HPV infection cannot join this study.
  • Severe allergic reactions: People who have had serious allergic reactions to vaccines or any components of the HPV vaccine in the past cannot participate.
  • Active infection or illness: People who have a current serious infection or illness that requires treatment cannot join the study at this time.
  • Previous treatment for HSIL: People who have already been treated for HSIL (high-grade squamous intra-epithelial lesions, which are abnormal cells that can develop into cancer) before joining the study cannot participate.
  • Inability to follow study requirements: People who cannot attend regular follow-up visits or complete the required study procedures cannot join.
  • Other medical conditions: People with certain other medical conditions that the study doctor believes would make participation unsafe or affect the study results cannot participate.
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Investigated drugs

  • Nonavalent HPV vaccine

    is a vaccine that protects against nine types of human papillomavirus (HPV). HPV is a virus that can cause abnormal cell changes and lesions in different parts of the body. This vaccine works by helping your immune system recognize and fight these specific types of HPV. In this trial, researchers are studying whether this vaccine can help prevent abnormal cell changes from coming back in patients who have already been treated for HPV-related lesions.

  • Placebo

    is an inactive substance that looks like the real vaccine but contains no active medication. It is used in this trial to compare the effects of the actual HPV vaccine against no treatment, which helps researchers determine if the vaccine is truly effective.

What is already known about the treatment

Nonavalent HPV Vaccine – This vaccine is given as an injection, typically administered in a series of shots into the muscle, and is designed to protect against nine types of human papillomavirus (HPV). Currently approved and widely used in medical practice for primary prevention, this vaccine is being studied in this trial for its potential role in preventing the return of precancerous lesions in patients who have already been treated for HPV-related abnormal cell changes. The vaccine works by introducing proteins that look like parts of the HPV virus into the body, which trains the immune system to recognize and fight these virus types if encountered in the future. It belongs to the class of preventive vaccines and is specifically categorized as a viral vaccine that provides protection against multiple strains of HPV associated with various cancers and precancerous conditions.

Investigated diseases

  • Vulvar Intraepithelial Neoplasia

    This is a condition where abnormal cells develop in the skin of the vulva, which is the outer part of the female genitals. These cells are considered high-grade when they show significant changes but have not yet become cancer. The condition is caused by human papillomavirus infection in most cases. Without treatment, these abnormal cells can persist or potentially progress over time. The lesions may appear as raised or flat areas on the vulvar skin. This condition can occur at any age but is more common in certain groups.

  • Vaginal Intraepithelial Neoplasia

    This condition involves abnormal cell growth in the lining of the vagina. The cells show precancerous changes but remain within the vaginal tissue layers. High-grade vaginal intraepithelial neoplasia indicates more severe cellular abnormalities. Human papillomavirus is the primary cause of this condition. The abnormal areas may not cause noticeable symptoms in many cases. These lesions can persist or develop further if left untreated.

  • Penile Intraepithelial Neoplasia

    This refers to abnormal cell changes occurring on the skin of the penis. The condition represents precancerous changes where cells appear abnormal under microscopic examination but have not invaded deeper tissues. High-grade lesions show more significant cellular abnormalities. Human papillomavirus infection is strongly associated with the development of this condition. The affected areas may appear as patches or spots on the penile skin. These changes can remain stable, regress, or progress over time.

  • Cervical Intraepithelial Neoplasia

    This condition involves abnormal cell growth on the surface of the cervix, which is the lower part of the uterus. High-grade cervical intraepithelial neoplasia means the cells show significant abnormal changes. The condition is primarily caused by persistent human papillomavirus infection. These cellular changes develop gradually over months to years. Most cases do not cause symptoms and are detected through screening tests. The abnormal cells remain on the surface layer of the cervix without spreading deeper.

  • Anal Intraepithelial Neoplasia

    This is a condition characterized by abnormal cell development in the lining of the anal canal. High-grade anal intraepithelial neoplasia indicates significant cellular changes that are precancerous in nature. Human papillomavirus infection is the main cause of this condition. The abnormal cells are confined to the surface layers of the anal tissue. Many people with this condition experience no symptoms. The cellular changes can persist, and without intervention, they may progress over time.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-520140-42-00Protocol code2024/4031Estimated enrolment984 patientsSponsorInstitut Gustave Roussy

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