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A Phase III Control Study of the Safety and Immunogenicity of vYF in Pediatric Population

Not Applicable
Recruiting
Conditions
Yellow Fever Immunization
Interventions
Biological: Yellow fever vaccine (live)
Biological: Measles, combinations with mumps and rubella, live attenuated
Registration Number
NCT07103148
Lead Sponsor
Sanofi
Brief Summary

The purpose of this study is to determine whether vYF (investigational vaccine) is safe and can help the body to develop antibodies (immunogenicity) compared with Stamaril vaccine and YF-VAX vaccine (both licensed vaccines) and when they are co-administered with Measles Mumps Rubella (MMR) vaccines in infants aged 11-15 months.

Number of Participants:

A total of 2440 participants is planned to be enrolled in VYF04 study.

Study Arms and Duration:

Eligible participants will be randomized in 2 independent groups (9-24 months, 2-5 years) to receive 1 dose of either vYF or Stamaril or YF-VAX in a 2:1:1 ratio within each age group. An additional group with participants of 11-15 months of age will also receive at the same vaccination visit vYF and a single dose of MMR vaccine.

For the 2nd step (YF booster vaccine administration in a subset), at the Year (Y) 3 visit, a subset of 120 participants of the 9-24 months of age group who did receive a YF vaccine on Day(D) 01 will be invited to join a booster dose assessment (booster dose administered after the Y3 visit blood sample has been taken). Participants aged 11 to 15 months at the time of the concomitant administration of vYF and MMR will not be eligible for receiving a booster dose.

The duration of each participation will be approximately 3 years for all participants (including participants co-administered on D01 with vYF and MMR), and 6 more months post-booster dose administration for the participants enrolled in the booster subset.

Detailed Description

The duration of each participant's participation will be up to approximately 3 years (not including booster phase in a subset)

The Phase III VYF04 is the first study to be carried out with the investigational vYF in pediatric populations.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
2440
Inclusion Criteria
  • Aged 9 months to 5 years on the day of inclusion*

    * "9 months to 5 years" means from the day of the 9th month after birth to the day before the 6th year birthday

  • Aged 11 to 15 months* on the day of inclusion for participants enrolled in the MMR co-administration group

    * "11 to 15 months" means from the day of the 11th month after birth to the day before the 16th month birthday

  • Participants who are healthy as determined by medical evaluation including medical history and physical examination

  • For infants*, born after a gestation period of 27 through 36 weeks and medically stable as assessed by the investigator, based on the following definition: "Medically stable" refers to the condition of premature infants who do not require significant medical support or ongoing management for debilitating disease and who have demonstrated a clinical course of sustained recovery by the time they receive the first dose of study intervention

    * Infants aged 9 months to 11 months up to the day before the 12th month birthday

  • Participant and parent/LAR are able to attend all scheduled visits and to comply with all study procedures

  • ICF has been signed and dated by the parent(s) or other LAR (and by an independent witness if required by local regulations)

Exclusion Criteria

Participants are excluded from the study if any of the following criteria apply:

  • Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy irradiation 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)

  • Known history of FV infection

  • Known systemic hypersensitivity to any of the study intervention components, eggs or history of a life-threatening reaction to the study interventions used in the study or to a product containing any of the same substances

  • Moderate or severe acute illness/infection (according to Investigator judgment) or febrile illness (temperature ≥ 38.0°C [≥ 100.4°F]) on the day of study intervention administration. A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided.

  • Chronic illness* that, in the opinion of the Investigator, is at a stage where it might interfere with study conduct or completion , including malignancy, such as leukemia, or lymphoma

    *Chronic illness may include, but is not limited to, cardiac disorders, renal disorders, auto-immune disorders, diabetes, psychiatric disorders or chronic infection

  • History of central nervous system disorder or disease, including seizures and febrile seizures

  • Receipt of any vaccine in the 4 weeks preceding the study intervention administration or planned receipt of any vaccine in the 4 weeks following the study intervention administration. Vaccine to be administered as part of the National Immunization Schedule will be postponed after the D29 visit

  • Previous vaccination against a FV disease at any time including YF with an investigational or marketed vaccine

  • Receipt of immune globulins, blood or blood-derived products in the past 6 months

  • Administration of any anti-viral within 2 months preceding the study intervention administration and up to the 6 weeks following the study intervention administration

  • For participants enrolled in the MMR co-administration group: previous vaccination against measles, measles/mumps/rubella

  • For participants enrolled in the MMR co-administration group: history of measles, mumps, rubella confirmed either clinically, serologically, or microbiologically

  • Known history or laboratory evidence of HIV infection

  • Known history of hepatitis B or hepatitis C seropositivity

  • Personal or family history of thymic pathology (thymoma, thymectomy, or myasthenia)

  • Participation at the time of study enrollment (or in the 4 weeks preceding the study intervention administration) or planned participation during the first year of the 3-year follow-up in another clinical study investigating a vaccine, drug, medical device, or medical procedure. Enrollment in another study after the first 6 months of follow-up is permitted, assuming it does not exclude participation in this study.

  • In an emergency setting, or hospitalized involuntary

  • Identified as a natural or adopted child of the Investigator or employee with direct involvement in the proposed study

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Group 1 (9-24 months)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of vYF vaccine at Day 1 Booster phase: 1 injection of vYF vaccine at Year 3 (in a subset)
Group 2 (9-24 months)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of Stamaril vaccine at Day 1 Booster phase: 1 injection of Stamaril vaccine at Year 3 (in a subset)
Group 3 (9-24 months)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of YF-VAX vaccine at Day 1 Booster phase: 1 injection of YF-VAX vaccine at Year 3 (in a subset)
Group 7 (approximately 11-15 months)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of MMR vaccine at Day 1 in a cohort of 11 to 15 months of age vaccinated with vYF
Group 7 (approximately 11-15 months)Measles, combinations with mumps and rubella, live attenuatedPrimary vaccination phase: 1 injection of MMR vaccine at Day 1 in a cohort of 11 to 15 months of age vaccinated with vYF
Group 4 (2-5 years)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of vYF vaccine at Day 1
Group 5 (2-5 years)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of Stamaril vaccine at Day 1
Group 6 (2-5 years)Yellow fever vaccine (live)Primary vaccination phase: 1 injection of YF-VAX vaccine at Day 1
Primary Outcome Measures
NameTimeMethod
Percentage of participants with seroconversion to YF virus after 1 dose of vYF compared to seroconversion after 1 dose of the Stamaril in YF-naive participants (9-24 months)At Day 29, 28 days post-vaccination (on Day 01) with vYF or Stamaril

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the pre-vaccination value

Percentage of participants with seroconversion to YF virus after 1 dose of vYF compared to seroconversion after 1 dose of the YF-VAX in YF-naive participants (9-24 months)At Day 29, 28 days post-vaccination (on Day 01) with vYF or YF-VAX

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the pre-vaccination value

Percentage of participants with seroconversion to YF virus after 1 dose of vYF compared to seroconversion after 1 dose of the Stamaril in YF-naive participants (2-5 years)At Day 29, 28 days post-vaccination (on Day 01) with vYF or Stamaril

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the pre-vaccination value

Percentage of participants with seroconversion to YF virus after 1 dose of vYF compared to seroconversion after 1 dose of the YF-VAX in YF-naive participants (2-5 years)At Day 29, 28 days post-vaccination (on Day 01) with vYF or YF-VAX

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the pre-vaccination value

Secondary Outcome Measures
NameTimeMethod
Percentage of participants, by age group, with seroconversion to YF virus in all investigational vaccine groups before (Day 01) and after investigational vaccine administration at various timepointsBefore and 28 days after the coadministration of MMR with vYF

Seroconversion is defined for measles, mumps and rubella respectively in participants seronegative at baseline as an antibody titer reaching the following thresholds for seropositivity:

* Anti-measles antibody concentrations ≥ 255 mIU/mL

* Anti-mumps antibody concentrations ≥ 10 (AbU)/mL

* Anti-rubella antibody concentrations ≥ 10 IU/mL

Percentage of participants, by age group, with seroprotection to YF virus in all investigational vaccine groups before (Day 01) and after investigational vaccine administration at various timepointsAt Day 01 and at Day 11 (in a subset), Day 15 (in a subset), Day 29, Month 6, and yearly from Year 1 to Year 3

Seroprotection is defined as NAb titers ≥ 10 (1/dil) at the corresponding timepoint

Geometric Mean Titers (GMTs) of neutralizing antibodies against YF virus in all investigational vaccine groups, by age group, before (Day 01) and after investigational vaccine administration at various timepointsAt Day 01 and at Day 11 (in a subset), Day 15 (in a subset), Day 29, Month 6, and yearly from Year 1 to Year 3

Antibody titers are expressed as geometric mean titers

Geometric Mean Titers Ratio (GMTRs) of neutralizing antibodies against YF virus in all investigational vaccine groups, by age group, before (Day 01) and after investigational vaccine administration at various timepointsGMTRs Day 11/Day 01 (subset only), Day 15/ D01 (subset only), Day 29/Day 01, Month 6/Day 01, Year 1/Month 6, Year 2/Year 1, Year 3/Year 2

At Day 01 and at Day 11 (in a subset), Day 15 (in a subset), Day 29, Month 6, and yearly from Year 1 to Year 3

Percentage of participants with seroconversion to YF virus in all investigational vaccine groups 28 days after the co-administration of vYF with measlescontaining vaccine in the MMR group and at successive timepoints28 days after the coadministration of MMR with vYF At Month 6 and yearly from Year 1 to Year 3

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the prevaccination value

Percentage of participants with seroprotection to YF virus in all investigational vaccine groups 28 days after the co-administration of vYF with measlescontaining vaccine in the MMR group and at successive timepoints28 days after the coadministration of MMR with vYF At Month 6 and yearly from Year 1 to Year 3

Seroprotection is defined as NAb titers ≥ 10 (1/dil) at the corresponding timepoint

GMTs of neutralizing antibodies against YF virus in all investigational vaccine groups 28 days after the co-administration of vYF with measlescontaining vaccine in the MMR group and at successive timepoints28 days after the coadministration of MMR with vYF At Month 6 and yearly from Year 1 to Year 3

Antibody titers are expressed as geometric mean titers

GMTRs of neutralizing antibodies against YF virus in all investigational vaccine groups 28 days after the co-administration of vYF with measlescontaining vaccine in the MMR group and at successive timepoints28 days after the coadministration of MMR with vYF At Month 6 and yearly from Year 1 to Year 3

GMTRs Day 29/Day 01, Month 6/Day 01, Year 1/Month 6, Year 2/Year 1, Year 3/Year 2

Percentage of participants with seroprotection to MMR before and 28 days after the coadministration of MMR with vYF in the MMR groupBefore and 28 days after the coadministration of MMR with vYF
GMTs of neutralizing antibodies against MMR virus before and 28 days after the coadministration of MMR with vYF in the MMR groupBefore and 28 days after the coadministration of MMR with vYF

Antibody titers are expressed as geometric mean titers

GMTRs of neutralizing antibodies against MMR virus before and 28 days after the coadministration of MMR with vYF in the MMR groupBefore and 28 days after the coadministration of MMR with vYF

GMTRs Day 29/Day 01

Percentage of participants with seroconversion to YF virus before the booster dose administration at Y3, then 10 days and 28 days after a vYF booster dose in the booster subsetAt Day 11 and Day 29 after booster dose

Seroconversion rates will be assessed using a YF MN assay Seroconversion is defined as a 4-fold increase in NAb titers as compared to the prevaccination value

Percentage of participants with seroprotection to YF virus before the booster dose administration at Y3, then 10 days and 28 days after a vYF booster dose in the booster subsetAt Day 11 and Day 29 after booster dose

Seroprotection is defined as NAb titers ≥ 10 (1/dil) at the corresponding timepoint

GMTs of neutralizing antibodies against YF virus before the booster dose administration at Y3, then 10 days and 28 days after a vYF booster dose in the booster subsetAt Day 11 and Day 29 after booster dose

Antibody titers are expressed as geometric mean titers

GMTRs of neutralizing antibodies against YF virus before the booster dose administration at Y3, then 10 days and 28 days after a vYF booster dose in the booster subsetAt Day 11 and Day 29 after booster dose

GMTRs Day 11/D01 and Day 29/Day 01

Percentage of participants with seroconversion to YF up to Day 29 will be described depending on the FV status at baseline (YF, Dengue, Zika) by age groupUp to Day 29

YF and Zika NAbs will be measured using a qualified MN assay Quantitation of human IgG antibodies against dengue virus (DENV) nonstructural protein 1 (NS1) in human sera will be determined using a qualified ELISA assay. Seroconversion is defined as a 4-fold increase in NAb titers as compared to the prevaccination value

Percentage of participants with seroprotection to YF up to Day 29 will be described depending on the FV status at baseline (YF, Dengue, Zika) by age groupUp to Day 29

Seroprotection is defined as NAb titers ≥ 10 (1/dil) at the corresponding timepoint

GMTs of neutralizing antibodies against YF up to Day 29 will be described depending on the FV status at baseline (YF, Dengue, Zika) by age groupUp to Day 29

Antibody titers are expressed as geometric mean titers

GMTRs of neutralizing antibodies against YF up to Day 29 will be described depending on the FV status at baseline (YF, Dengue, Zika) by age groupUp to Day 29

GMTRs Day 29/Day 01

Number of participants with immediate adverse eventsWithin 30 minutes after each vaccination

Immediate adverse events are any unsolicited systemic adverse events reported in the 30 minutes after vaccination

Number of participants with solicited injection site reactionsWithin 7 days after each vaccination

Solicited injection site reactions:

* for participants \< 24 months include: injection site tenderness, injection site erythema, injection site swelling

* for participants aged ≥ 2 years and \< 5 years include: injection site pain, injection site erythema and injection site swelling

Number of participants with solicited systemic reactionsWithin 14 days after each vaccination

Solicited systemic reactions:

* for participants \< 24 months include: fever, vomiting, crying abnormal, drowsiness, appetite lost, irritability

* for participants aged ≥ 2 years and \< 5 years include: fever, headache, fatigue and myalgia

Number of participants with unsolicited adverse events (AEs)Within 28 days after each vaccination

Unsolicited (spontaneously reported) AEs, not fulfilling criteria for solicited adverse reactions

Number of participants with medically attended adverse events (MAAEs)From Day 01 to Day 29

MAAEs will be collected as part of the unsolicited AEs

Number of participants with serious adverse events (SAEs) and adverse events of special interest (AESIs)From Day 01 to Month 6 and from Year 3 to Year 3 + 6 Months for the booster subset

SAEs and AESIs

Hematology in a subset of participants 9-24 months of age and in a subset of participants aged 2-5 yearsAt Day 01 and at Day 05

Blood samples will be taken for the determination of hematology

Biochemistry in a subset of participants 9-24 months of age and in a subset of participants aged 2-5 yearsAt Day 01 and at Day 05

Blood samples will be taken for the determination of biochemistry

YF vaccinal viremia in each vaccine groups (vYF, Stamaril and YF-VAX) in a subset of participants 9-24 months of ageAt Day 01 and at Day 05

YF vaccinal viremia will be measured by YF-specific quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay

Trial Locations

Locations (1)

Investigational Site Number : 4840013

🇲🇽

Cuernavaca, Morelos, Mexico

Investigational Site Number : 4840013
🇲🇽Cuernavaca, Morelos, Mexico

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