Immunogenicity and Safety Study of an Investigational Quadrivalent Meningococcal Conjugate Vaccine Administered in Healthy Infants and Toddlers in China

A Phase 3, Modified-double Blind, Multi-center Study of the Immunogenicity and Safety of an Investigational Quadrivalent Meningococcal Conjugate Vaccine Administered in Healthy Infants and Toddlers (2 to 23 Months of Age) in China

The purpose of this study is to describe the safety and immunogenicity of MenACYW conjugate vaccine compared with locally-licensed meningococcal vaccines in healthy infants and toddlers in China.

Study details include:

• Study duration (including 6-month safety follow-up after the last dose): - Cohort I (Groups 1 and 2): approximately 211 or 271 days (approximately 7 or 9 months) - Cohort II (Groups 3 and 4): up to 18 months - Cohort III (Groups 5 and 6): up to 21 months - Cohort III (Group 7): approximately 16 months
• Vaccination Visits Period:
• Cohort I (Groups 1 and 2): a 2-dose vaccination at V01 (D01) and V02 (D31) or V03 (D91). Two blood samples are collected pre-vaccination (D01) and 30 days post the 2nd dose of vaccination (D61 or D121). Telephone calls (TCs) are planned on the 4th, the 9th, and the 21st day after each vaccination, and 5 TCs (1 TC/month) are planned for the 5 months post the last on-site visit for safety follow-up. For participants receiving the second vaccination with a 3-month interval: an on-site visit is planned 30 days post the 1st dose of vaccination (V02, D31) for participant diary collection.
• Cohort II (Groups 3 and 4): a 2-dose vaccination at V01 (D01) and V02 (D31) or V03 (D91). A 1-dose booster is planned for Group 3 only at 18 MoA (within the 18th month from the participant's birth date). Up to 4 blood samples will be collected. In the primary vaccination period, blood samples are collected before the first primary vaccination (D01) and 30 days post the 2nd dose of primary vaccination (D61 or D121). A blood sample will be collected from all participants at 18 MoA. A post-booster blood sample will be collected from participants in Group 3, 30 days post their booster vaccination. Telephone calls are planned on the 4th, the 9th, and the 21st day after each vaccination (including the booster dose), and 5 TCs (1 TC/month) are planned for the 5 months post the last on-site visit of the primary and the booster vaccination periods, respectively, for safety follow-up. For participants receiving the second vaccination with a 3-month interval: an on-site visit is planned 30 days post the 1st dose of vaccination (V02, D31) for participant diary collection. - Cohort III - Groups 5 and 6: a 3-dose primary vaccination at V01 (D01), V02 (D31) and V03 (D61), a 1-dose booster at 12 MoA (within the 12th months from the participant's birth date) on V05 or at 18 MoA (within the 18th months from the participant's birth date) on V06.

In total 4 blood samples are to be collected. In the primary vaccination period, blood samples are to be collected before the first primary vaccination (D01) and 30 days post the 3rd dose of primary vaccination (D91); in the booster vaccination period, blood samples are to be collected before booster vaccination at V05 (for participants receiving the booster at 12 MoA) or V06 (for participants receiving the booster at 18 MoA), and 30 days post booster vaccination (V05 + 30 days or V06 + 30 days). Telephone calls are planned on the 4th, the 9th, and the 21st day after each vaccination (including the booster dose), and 5 TCs (1 TC/month) are planned for the 5 months post the last on-site visit of the primary and the booster vaccination periods respectively for safety follow-up.

- Cohort III - Group 7: a 3-dose primary vaccination at V01 (D01), V02 (D61) and V03 (D121), a 1-dose booster at V05 at 12 MoA (within the 12th months from the participant's birth date).

In total 4 blood samples are to be collected. In the primary vaccination period, blood samples are to be collected before the first primary vaccination (D01) and 30 days post the 3rd dose of primary vaccination (D151); in the booster vaccination period, blood samples are to be collected before booster vaccination at V05 and 30 days post booster vaccination (V06). Telephone calls are planned on the 4th, the 9th, and the 21st day after each vaccination (including the booster dose), and 5 TCs (1 TC/month) are planned for the 5 months post the last on-site visit of the primary and the booster vaccination periods (ie, V04 and V06), respectively, for safety follow-up. A safety visit is planned on the 9th day after the first vaccination for the ESDR participants (the first 30 participants in this group).

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy Volunteers; Meningococcal Infection
• Intervention / Treatment: Biological: MenQuadfi® (Meningococcal Polysaccharide [Serogroups A, C, W, and Y] Tetanus Toxoid Conjugate Vaccine) (Sanofi Pasteur Inc., Swiftwater, PA, USA); Biological: Menhycia® (ACYW135 Meningococcal Conjugate Vaccine [CRM197]) (CanSino Biologics Inc., China)

• Study Type: Interventional
• Enrollment (Estimated): 4568
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Trial Transparency email recommended (Toll free for US & Canada); Phone Number: option 6 800-633-1610; Email: Contact-US@sanofi.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• For Cohort I: Aged 12 months through 23 months on the day of inclusion. For Cohort II: Aged 6 months through 11 months on the day of inclusion. For Cohort III: Aged 2 months through 5 months on the day of inclusion - Born at full term of pregnancy (≥37 weeks) or born after a gestation period of 27 through 36 weeks and medically stable as assessed by the investigator - Informed consent form has been signed and dated by the parent(s) or other LAR (and by an independent witness if required by local regulations). - Participant and parent/LAR are able to attend all scheduled visits and to comply with all study procedures. Exclusion Criteria:
• Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy; or long-term systemic corticosteroid therapy - History of meningococcal infection - History of any neurological disorders - History of Guillain-Barré syndrome - History of an Arthus-type hypersensitivity reaction after a previous dose of tetanus toxoid-containing vaccine - At high risk for meningococcal infection during the study - Known systemic hypersensitivity to any of the study intervention components, 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 - Self-reported thrombocytopenia, contraindicating intramuscular injection - Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating intramuscular injection - Chronic illness 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) or febrile illness (axillary temperature ≥37.5°C [99.5℉]) 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. - Receipt of any live vaccines within 14 days preceding the trial vaccination or planned receipt of any live vaccines in 14 days following trial vaccination, and receipt of any inactivated vaccines in 8 days preceding the trial vaccination or planned receipt of any live vaccines in 8 days following trial vaccination - For Cohort I (12 to 23 MoA): receipt of any other meningococcal vaccine except the meningococcal group A polysaccharide vaccine included in the NIP. The time since last vaccination of meningococcal group A or groups A and C polysaccharide vaccine of 6 months or less should be excluded. - For Cohorts II (6 to 11 MoA) and III (2 to 5 MoA): a vaccination history of any meningococcal vaccine. - Receipt of immune globulins, blood or blood-derived products in the past 3 months. - Receipt of oral or injectable antibiotic therapy within 72 hours prior to the first blood draw. - Participation at the time of study enrollment (or in the 4 weeks preceding the study intervention administration) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure. - In an emergency setting, or being hospitalized - Identified as a natural or adopted child of the Investigator or employee with direct involvement in the proposed study The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

7

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort I: Group 1MenACYW 2-dose schedule; 2 doses of MenACYW conjugate vaccine to participants aged 12 through 23 MoA	Biological: MenQuadfi® (Meningococcal Polysaccharide [Serogroups A, C, W, and Y] Tetanus Toxoid Conjugate Vaccine) (Sanofi Pasteur Inc., Swiftwater, PA, USA); Pharmaceutical form:Liquid solution-Route of administration:IM injection; Other Names: 395
Active Comparator: Cohort I: Group 2 MenACYW135, CanSino 2-dose schedule; 2 doses of MenACYW135, CanSino conjugate vaccine to participants aged 12 through 23 MoA	Biological: Menhycia® (ACYW135 Meningococcal Conjugate Vaccine [CRM197]) (CanSino Biologics Inc., China); Pharmaceutical form:Lyophilized powder (MenAC conjugate vaccine) and liquid solution (MenYW135 conjugate vaccine)-Route of administration:IM injection
Experimental: Cohort II: Group 3MenACYW 2-dose primary vaccination + 1-dose booster schedule; 2-dose primary vaccination and 1-dose booster of MenACYW conjugate vaccine to participants aged 6 through 11 MoA	Biological: MenQuadfi® (Meningococcal Polysaccharide [Serogroups A, C, W, and Y] Tetanus Toxoid Conjugate Vaccine) (Sanofi Pasteur Inc., Swiftwater, PA, USA); Pharmaceutical form:Liquid solution-Route of administration:IM injection; Other Names: 395
Active Comparator: Cohort II: Group 4 MenACYW135, CanSino 2-dose schedule; 2-dose primary vaccination and 1-dose booster of MenACYW135, CanSino conjugate vaccine to participants aged 6 through 11 MoA	Biological: Menhycia® (ACYW135 Meningococcal Conjugate Vaccine [CRM197]) (CanSino Biologics Inc., China); Pharmaceutical form:Lyophilized powder (MenAC conjugate vaccine) and liquid solution (MenYW135 conjugate vaccine)-Route of administration:IM injection
Experimental: Cohort III: Group 5 MenACYW 3-dose primary vaccination + 1-dose booster schedule; 3-dose primary vaccination and 1-dose booster of MenACYW conjugate vaccine to participants aged 3 through 5 MoA	Biological: MenQuadfi® (Meningococcal Polysaccharide [Serogroups A, C, W, and Y] Tetanus Toxoid Conjugate Vaccine) (Sanofi Pasteur Inc., Swiftwater, PA, USA); Pharmaceutical form:Liquid solution-Route of administration:IM injection; Other Names: 395
Active Comparator: Cohort III: Group 6 MenACYW135, CanSino 3-dose primary vaccination + 1-dose booster schedule; 3-dose primary vaccination and 1-dose booster of MenACYW135, CanSino conjugate vaccine to participants aged 3 through 5 MoA	Biological: Menhycia® (ACYW135 Meningococcal Conjugate Vaccine [CRM197]) (CanSino Biologics Inc., China); Pharmaceutical form:Lyophilized powder (MenAC conjugate vaccine) and liquid solution (MenYW135 conjugate vaccine)-Route of administration:IM injection
Experimental: Cohort III: Group 7 MenACYW 3-dose primary vaccination + 1-dose booster schedule; 3-dose primary vaccination and 1-dose booster of MenACYW conjugate vaccine to participants aged 2 MoA	Biological: MenQuadfi® (Meningococcal Polysaccharide [Serogroups A, C, W, and Y] Tetanus Toxoid Conjugate Vaccine) (Sanofi Pasteur Inc., Swiftwater, PA, USA); Pharmaceutical form:Liquid solution-Route of administration:IM injection; Other Names: 395

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participants 12 through 23 MoA (Cohort I): Vaccine seroresponse to meningococcal serogroups A, C, Y, and W	30 days post-2nd vaccination rSBA titer ≥1:8 for participants with pre-vaccination rSBA titer <1:8, or At least 4-fold increase in rSBA titer from pre- to 30 days post-2nd vaccination for participants with pre-vaccination rSBA titer ≥1:8	30 days post 2nd vaccination (up to Day 121)
Participants 12 through 23 MoA (Cohort I): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W measured by rSBA	30 days (+10 days) post-2nd vaccination with MenACYW conjugate vaccine or MenACYW135, CanSino conjugated vaccine	30 days post 2nd vaccination (up to Day 121)
Participants 6 through 11 MoA (Cohort II): Vaccine seroresponse to meningococcal serogroups A, C, Y, and W	30 days post-2nd vaccination rSBA titer ≥1:8 for participants with pre-vaccination rSBA titer <1:8, or At least 4-fold increase in rSBA titer from pre- to 30 days post-2nd vaccination for participants with pre-vaccination rSBA titer ≥1:8	30 days post 2nd vaccination (up to Day 121)
Participants 6 through 11 MoA (Cohort II): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA	30 days (+10 days) post-2nd vaccination of the primary series with MenACYW conjugate vaccine or MenACYW135, CanSino conjugated vaccine	30 days post 2nd vaccination (up to Day 121)
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Vaccine seroresponse to meningococcal serogroups A, C, Y, and W	30 days post-3rd vaccination rSBA titer ≥1:8 for participants with pre-vaccination rSBA titer <1:8, or At least 4-fold increase in rSBA titer from pre- to 30 days post-3rd vaccination for participants with pre-vaccination rSBA titer ≥1:8	Day 91
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA	30 days (+10 days) post-3rd vaccination of the primary series with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine	Day 91
Participants 2 through 5 MoA (Cohort III - Groups 7 and 6): Vaccine seroresponse to meningococcal serogroups A, C, Y, and W	30 days post-3rd vaccination rSBA titer ≥1:8 for participants with pre-vaccination rSBA titer <1:8, or At least 4-fold increase in rSBA titer from pre- to 30 days post-3rd vaccination for participants with pre-vaccination rSBA titer ≥1:8	Day 151
Participants 2 through 5 MoA (Cohort III - Groups 7 and 6): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA	30 days (+10 days) post-3rd vaccination of the primary series with MenACYW conjugate vaccine (Group 7) or MenACYW135, CanSino conjugate vaccine (Group 6)	Day 151

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with immediate adverse events (AEs)	Unsolicited systemic AEs that occur within 30 minutes after vaccination	Within 30 minutes post-vaccination
Presence of solicited injection site reactions	(pre-listed in the participant diary and CRF)	for 8 days, including the day of each study vaccination.
Presence of solicited systemic reactions	(pre-listed in the participant diary and CRF)	for 8 days, including the day of each study vaccination.
Presence of unsolicited AEs		for 30 days including the day of each study vaccination.
Presence of SAEs		Approximately 7 months to 9 months for Group 1 and Group 2; up to 18 months for participants from Group 3 and Group 4; up to 21◦months for participants from Group 5 and Group 6; Approximately 16 months for participants from Group 7
Presence of AEs leading to study discontinuation		Approximately 7 months to 9 months for Group 1 and Group 2; up to 18 months for participants from Group 3 and Group 4; up to 21◦months for participants from Group 5 and Group 6; Approximately 16 months for participants from Group 7
Participants 12 through 23 MoA (Cohort I) Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA 30 days (+10 days) post-2nd vaccination with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine.		30 days post 2nd vaccination (up to Day 121)
Participants 6 through 11 MoA (Cohort II) Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA	30 days (+10 days) post-2nd vaccination of the primary series with MenACYW conjugate vaccine or MenACYW135, CanSino conjugated vaccine.	30 days post 2nd vaccination (up to Day 121)
Participants 6 through 11 MoA (Cohort II) Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA pre-booster dose at 18 MoA.		at 18 MoA (up to Day 394)
Participants 6 through 11 MoA (Cohort II) Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA pre-booster dose at 18 MoA		at 18 MoA (up to Day 394)
Participants 6 through 11 MoA (Cohort II) Antibody titers (in terms of GMTs) against booster meningococcal serogroups A, C, Y, and W, measured by rSBA 30 days (+10 days) post-booster vaccination with MenACYW conjugate vaccine given at 18 MoA.		at 18 MoA (up to Day 424)
Participants 6 through 11 MoA (Cohort II) Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA 30 days (+10 days) after one dose of booster vaccination of MenACYW conjugate vaccine		at 18 MoA (up to Day 424)
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA	30 days (+10 days) post-3rd vaccination of the primary series with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine.	D91
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA	pre-booster dose at 12 and 18 MoA with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine	at 12 and 18 MoA (up to Day 484)
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W, measured by rSBA	pre-booster dose at 12 and 18 MoA with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine	at 12 and 18 MoA (up to Day 484)
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA	30 days (+10 days) post-booster vaccination at 12 and 18 MoA with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine	30 days after 12 and 18 MoA (up to Day 514)
Participants 3 through 5 MoA (Cohort III -Groups 5 and 6): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W, measured by rSBA	30 days (+10 days) post-booster vaccination at 12 and 18 MoA with MenACYW conjugate vaccine or MenACYW135, CanSino conjugate vaccine	30 days after 12 and 18 MoA (up to Day 514)
Participants 2 MoA (Cohort III - Group 7): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W measured by rSBA 30 days (+10 days) post-3rd vaccination of the primary series with MenACYW conjugate vaccine (Group 7).		D151
Participants 2 MoA (Cohort III - Group 7): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA pre-booster dose at 12 MoA (Group 7) with MenACYW conjugate vaccine		at 12 MoA (up to Day 333)
Participants 2 MoA (Cohort III - Group 7): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W, measured by rSBA pre-booster dose at 12 MoA (Group 7) with MenACYW conjugate vaccine		at 12 MoA (up to Day 333)
Participants 2 MoA (Cohort III - Group 7): Antibody titers (in terms of GMTs) against meningococcal serogroups A, C, Y, and W, measured by rSBA 30 days (+10 days) post-booster vaccination with MenACYW conjugate vaccine at 12 MoA (Group 7)		30 days after 12 MoA (up to Day 363)
Participants 2 MoA (Cohort III - Group 7): Antibody titers ≥1:8 and ≥1:128 against meningococcal serogroups A, C, Y, and W, measured by rSBA 30 days (+10 days) post-booster vaccination with MenACYW conjugate vaccine at 12 MoA (Group 7)		30 days after 12 MoA (up to Day 363)

Collaborators and Investigators

• Sponsor: Sanofi

Study record dates

Study Major Dates

• Study Start (Estimated): August 20, 2026
• Primary Completion (Estimated): March 13, 2028
• Study Completion (Estimated): July 26, 2029

Study Registration Dates

• First Submitted: July 13, 2026
• First Submitted That Met QC Criteria: July 13, 2026
• First Posted (Actual): July 17, 2026

Study Record Updates

• Last Update Posted (Actual): July 17, 2026
• Last Update Submitted That Met QC Criteria: July 13, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Infections; Bacterial Infections; Bacterial Infections and Mycoses; Gram-Negative Bacterial Infections; Neisseriaceae Infections; Meningococcal Infections; CRM197 (non-toxic variant of diphtheria toxin)
• Other Study ID Numbers: MEQ00093; U1111-1316-0126 (Registry Identifier: ICTRP)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No