Study of Purified Vero Rabies Vaccine Compared With Two Reference Rabies Vaccines, Given in a Pre-exposure Regimen to Children and Adults and as Single Booster Dose to a Subset of Adults

Investigation of Rabies Vaccination Regimens in Children and Adults

Not Recruiting
1 year or above
All
Phase 3
1708 participants needed

Study Overview

The primary objective of this study is:

To demonstrate the VRVg-2 is non-inferior to Verorab and Imovax Rabies vaccines in each age group (pediatric and adult populations) when administered as a 3-dose PrEP regimen, in terms of proportion of participants achieving a rabies virus neutralizing antibody (RVNA) titer ≥ 0.5 IU/mL at Day 42, ie. 14 days after the 3rd injection (for Primary Series Cohort 1).

The secondary objectives of this study are: First 1-5 with hypotheses testing will be evaluated sequentially - only if the previous objective is achieved, will the next objective be tested

To demonstrate that:

  • the observed proportion of participants in the VRVg2(VRVg) group at D42 is at least 99% with a lower limit of the 95% confidence interval (CI) of at least 97%
  • VRVg is non inferior (NI) to Verorab and Imovax Rabies vaccines (Imovax) in each age group at D28
  • 2-dose VRVg at D28 is NI to 3-dose Imovax at D42 in each age group
  • the observed proportion of participants in the VRVg group at D28 is at least 99% with a lower limit of the 95% CI of at least 97%
  • 2-dose Imovax at D28 is NI to 3-dose Imovax at D42 in overall participants (Cohort1)

To describe:

  • the immune response induced by VRVg versus Verorab and Imovax at D28 and at D42 in all age groups
  • the immune response induced by VRVg at D14 after a booster dose of VRVg administered at M12 (Cohort1) and between M24 up to M36 (Cohort2)
  • the persistence of immune response at M6,12,18, and pre-booster between M24 up to M36 post-primary series vaccination (Cohort2)
  • safety profile of VRVg versus Verorab and Imovax in primary series and after a booster dose of VRVg

Study Details

The duration of each participant's participation in the primary series Cohort 1 of the study will be approximately 7 months (28 day-vaccination period followed by 6-month safety follow-up period). For the subset of adult participants in Booster Phase Cohort 1 who received a single booster dose of VRVg-2 (1 booster dose 365 days after primary series followed by 6-month safety follow-up period), the duration will be approximately 18 months.

For Primary Series Cohort 2, the duration of each participant's participation in the study will be approximately 7 months (one week vaccination period followed by 6-month safety follow-up period).

For the subset of adult participants in Immunogenicity Persistence and Booster Phase Cohort 2 who will be followed-up for evaluation of immunogenicity persistence after primary series (including blood samples collection at M6, M12, M18, and between 24 up to 36 months) and who will receive a single booster dose of VRVg-2 (after the blood sample collection between 24 up to 36 months), the duration will be approximately 30 to 42 months.

Eligibility Criteria

You may be eligible for this study if you meet the following criteria:

  • Conditions: Rabies, Healthy Volunteers
  • Age: 1 year or above
  • Gender: All

Inclusion Criteria:

  • Aged ≥1 year on the day of inclusion
    • Cohort 1 - pediatrics (>1 to 17 years old) and adult (≥18 years old)
    • Cohort 2 - all adults (≥18 years old)
  • Informed consent form has been signed and dated by the participant and /or and

    parent(s) or legally acceptable representative (LAR) and by an independent witness (if required by local regulations), as necessary; and assent form has been signed and dated by the participant, as required

  • Participant (adult ≥18 years) or participant and parent/LAR (1 year to <18 years) are able to attend all scheduled visits and to comply with all study procedures.

Exclusion Criteria:

  • Participant is pregnant, or lactating, or of childbearing potential and not using an effective method of contraception or abstinence from at least 4 weeks prior to the first vaccination until 1 month after each vaccination. To be considered of non-childbearing potential, a female must be pre-menarche or post-menopausal for at least 1 year, or surgically sterile.
  • Participation at the time of study enrollment or, planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure.
  • Receipt of any vaccine in the 4 weeks (28 days) preceding the first study vaccination or planned receipt of any vaccine prior to Visit 5 for pediatric participants and adult participants in Cohort 1, and prior to Visit 4 for adult participants in Cohort 2.
  • Previous vaccination against rabies (in pre- or post-exposure regimen) with either the study vaccines or another vaccine.
  • Bite by, or exposure to a potentially rabid animal in the previous 6 months with or without post-exposure prophylaxis.
  • Receipt of immune globulins, blood or blood-derived products in the past 3 months.
  • Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months).
  • At high risk for rabies exposure during the study.
  • Known systemic hypersensitivity to any of the study/control vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a vaccine containing any of the same substances.
  • Self-reported thrombocytopenia, contraindicating intramuscular vaccination.
  • Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating intramuscular vaccination.
  • Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily.
  • Current alcohol or substance abuse that, in the opinion of the investigator, might interfere with the study conduct or completion.
  • Chronic illness(1) that, in the opinion of the Investigator, is at a stage where it might interfere with study conduct or completion.
  • Moderate or severe acute illness/infection (according to Investigator judgment) on the day of vaccination or febrile illness (temperature ≥ 38.0°C). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided.
  • Personal history of Guillain-Barré syndrome.
  • Identified as an Investigator or employee of the Investigator or study center with direct involvement in the proposed study, or identified as an immediate family member (ie, parent, spouse, natural or adopted child) of the Investigator or employee with direct involvement in the proposed study.
    1. Chronic illness may include, but is not limited to, neurological, cardiopulmonary, gastrointestinal, renal, genitourinary, metabolic, hematologic, auto-immune, or psychiatric disorders or infection

This study investigates the effectiveness of an investigational rabies vaccine compared to two reference rabies vaccines in both children and adults. The purpose is to determine if the investigational vaccine can provide an immune response that is not inferior to the standard vaccines when given as a three-dose pre-exposure regimen. The study will measure the rabies virus neutralizing antibody levels in participants to assess the immune response.

Participants in the study will receive either the investigational vaccine or one of the two reference vaccines. The study will involve multiple blood tests to measure the immune response at different time points. Safety and any side effects will also be monitored throughout the study. Some adult participants will receive a booster dose, and their immune response will be evaluated after this additional dose.

  • Who can participate: Children aged over 1 year and adults are eligible to participate. Key eligibility factors include the ability to attend all study visits and compliance with procedures. Participants must not have previous rabies vaccinations or recent exposure to rabies.
  • Study details: Participants will receive vaccinations and undergo blood tests to monitor immune response. Those in the booster phase will receive an additional dose. The study includes safety monitoring for any side effects.
Updated on 04 Jul 2025. Study ID: NCT04127786