Phase 1/2 Study of Chlamydia Trachomatis mRNA Vaccine in Adults Aged 18 to 29 Years

NCT06891417 | Recruiting Phase 1 FDA Drug

• 2 other identifiers: VAV00023U1111-1308-7349
• Study Type: interventional
• Target: 1,560
• Locations: 1 country
• Sites: 7

Brief Summary

The purpose of this study is to evaluate the safety, efficacy, and immunogenicity of different dose levels (low, medium, and high) of Chlamydia messenger ribonucleic acid (mRNA) Vaccine candidate in adult participants aged 18 to 29 years. This study will consist of 3 Sentinel Cohorts and a Main Cohort, with the Sentinel Cohorts assessing the safety of the different dose levels in a stepwise manner. All participants will be followed up to 12 months after the last study intervention administration. Thus, the expected duration of the participant's involvement will be 18 months.

Conditions

Chlamydia Trachomatis Immunization

Keywords

Chlamydia

Outcome Measures

Primary Outcomes (7)

• Presence of immediate unsolicited systemic adverse events (AEs)

  Number of participants with immediate unsolicited systemic adverse events (AEs) reported in the 30 minutes after each vaccine injection.

  Within 30 minutes after each vaccine injection

• Presence of solicited injection site and systemic reactions

  Number of participants with solicited injection site and systemic reactions occurring up to 7 days after each vaccine injection.

  Up to 7 days after each vaccine injection

• Presence of unsolicited AEs

  Participants with unsolicited AEs reported up to 28 days after each vaccine injection.

  Up to 28 days after each vaccine injection.

• Presence of medically attended adverse events (MAAEs)

  Number of participants with MAAEs reported after each vaccine injection and up to 6 months after last vaccine injection.

  Up to 6 months after last vaccine injection

• Presence of all serious AEs (SAEs) and all adverse events of special interest (AESIs)

  Number of participants with SAEs and all AESIs reported after each vaccine injection and up to 12 months after last vaccine injection

  Up to 12 months after last vaccine injections

• Presence of related SAEs, and fatal SAEs

  Number of participants with related SAEs, and fatal SAEs throughout the study

  Throughout the study, appriximatley 18 months

• Presence of out-of-range biological test results (Sentinel Cohort and Safety Subset of Main Cohort)

  Number of participants with out-of-range biological test results up to 7 days after each vaccine injection

  Up to 7 days after each vaccination injections

Secondary Outcomes (2)

• Assessment of serum binding antibodies to specific Chlamydia trachomatis antigens and whole bacteria in immunogenicity subset

  Before each vaccine injection through 1 month after each vaccine injection

• Geometric mean cell-mediated immune response of antigen-specific T helper type 1 (Th1) and T helper type 2 (Th2) cytokine-producing T cells by phenotype

  Before each vaccine injection through 1 month after each vaccine injection

Study Arms (16)

Sentinel Cohort A Group 1: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three low dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort B Group 2: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three medium dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort C Group 3: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three high dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort A, B and C Group 4: Chlamydia trachomatis Seronegative

PLACEBO COMPARATOR

Participants will receive three injections of Placebo

Other: Placebo

Sentinel Cohort A Group 5: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three low dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort B Group 6: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three medium dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort C Group 7: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three medium dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Sentinel Cohort A, B and C Group 8: Chlamydia trachomatis Seropositive

PLACEBO COMPARATOR

Participants will receive three injections of Placebo

Other: Placebo

Main Cohort Group 9: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three low dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 10: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three medium dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 11: Chlamydia trachomatis Seronegative

EXPERIMENTAL

Participants will receive three high dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 12: Chlamydia trachomatis Seronegative

PLACEBO COMPARATOR

Participants will receive three injections of Placebo

Other: Placebo

Main Cohort Group 13: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three low dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 14: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three medium dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 15: Chlamydia trachomatis Seropositive

EXPERIMENTAL

Participants will receive three high dose injections of Chlamydia mRNA Vaccine

Biological: Chlamydia mRNA Vaccine

Main Cohort Group 16: Chlamydia trachomatis Seropositive

PLACEBO COMPARATOR

Participants will receive three injections of Placebo

Other: Placebo

Interventions

Chlamydia mRNA Vaccine BIOLOGICAL

Pharmaceutical Form: Suspension for injection Route of Administration: Intramuscular injection

Main Cohort Group 10: Chlamydia trachomatis Seronegative; Main Cohort Group 11: Chlamydia trachomatis Seronegative; Main Cohort Group 13: Chlamydia trachomatis Seropositive; Main Cohort Group 14: Chlamydia trachomatis Seropositive; Main Cohort Group 15: Chlamydia trachomatis Seropositive; Main Cohort Group 9: Chlamydia trachomatis Seronegative; Sentinel Cohort A Group 1: Chlamydia trachomatis Seronegative; Sentinel Cohort A Group 5: Chlamydia trachomatis Seropositive; Sentinel Cohort B Group 2: Chlamydia trachomatis Seronegative; Sentinel Cohort B Group 6: Chlamydia trachomatis Seropositive; Sentinel Cohort C Group 3: Chlamydia trachomatis Seronegative; Sentinel Cohort C Group 7: Chlamydia trachomatis Seropositive

Placebo OTHER

Pharmaceutical Form: Solution for injection Route of Administration: Intramuscular injection

Main Cohort Group 12: Chlamydia trachomatis Seronegative; Main Cohort Group 16: Chlamydia trachomatis Seropositive; Sentinel Cohort A, B and C Group 4: Chlamydia trachomatis Seronegative; Sentinel Cohort A, B and C Group 8: Chlamydia trachomatis Seropositive

Eligibility Criteria

• Age: 18 Years - 29 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• New sex partner within the past 6 months, or more than one current sex partner, or partner with known previous or coexisting sexually transmitted infection (STI), or inconsistent condom use
• A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies:
• Is of non-childbearing potential. To be considered of non-childbearing potential, a female must be surgically sterile.
• Is of childbearing potential and agrees to use an effective contraceptive method from at least 4 weeks prior to study intervention administration until at least 4 weeks after the last study intervention administration.
• A female participant of childbearing potential must have a negative highly sensitive pregnancy test (urine or serum as required by local regulation) at the screening visit and before each subsequent study intervention administration

You may not qualify if:

• Any screening laboratory parameter with laboratory abnormalities as per local reference range and that are greater than Grade 2 or deemed clinically significant in the opinion of the Investigator
• Participants who are Chlamydia trachomatis (CT) and/or Neisseria gonorrhea (NG) NAAT positive at screening visit
• Self-reported or documented seropositivity for HIV antigen and/or antibodies (Abs), hepatitis B virus surface antigen (HBsAg), hepatitis B core antibodies (HBcAbs), or hepatitis C virus (HCV) Abs infection at screening visit
• 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)
• Known systemic hypersensitivity to any of the study intervention components, or history of a life-threatening reaction to the study intervention(s) used in the study or to a product containing any of the same substances
• Previous history of myocarditis, pericarditis, and/or myopericarditis
• Known history of previous history of Guillain-Barre syndrome and other immune mediated demyelinating conditions that include but are not limited to Multiple Sclerosis (MS), Neuromyelitis Optica (NMO), acute disseminated encephalomyelitis (ADEM), Transverse myelitis
• Screening electrocardiogram (ECG) value that is consistent with possible myocarditis, pericarditis, and/or myopericarditis or screening ECG that demonstrates clinically relevant abnormalities, per investigator, that may affect participant safety or study results
• Self-reported thrombocytopenia, contraindicating intramuscular injection, based on investigator's judgment
• 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 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
• Alcohol, prescription drug, or substance abuse that, in the opinion of the Investigator, might interfere with the study conduct or completion
• Receipt of any mRNA vaccine/product in the 2 months preceding study enrollment or planned receipt of any mRNA vaccine/product within the 2 months following any study intervention administration
• Receipt of any vaccine (other than the study vaccine) in the 4 weeks preceding any study intervention administration or planned receipt of any vaccine (other than the study vaccine) in the 4 weeks following any study intervention administration, except influenza which may be received at least 2 weeks before or 2 weeks after any study vaccination
• Receipt of immune globulins, blood, or blood-derived products in the past 3 months

Sponsors & Collaborators

• Sanofi: lead

Study Sites (7)

Investigational Site Number : 0360002

Bruce, Australian Capital Territory, 2617, Australia

RECRUITING

Investigational Site Number : 0360006

Maroubra, New South Wales, 2035, Australia

RECRUITING

Investigational Site Number : 0360005

Sydney, New South Wales, 2010, Australia

RECRUITING

Investigational Site Number : 0360001

Albion, Queensland, 4010, Australia

RECRUITING

Investigational Site Number : 0360004

Morayfield, Queensland, 4506, Australia

RECRUITING

Investigational Site Number : 0360003

Southport, Queensland, 4222, Australia

RECRUITING

Investigational Site Number : 0360010

Melbourne, Victoria, 3000, Australia

RECRUITING

Related Links

• VAV00023 Plain Language Results Summary

MeSH Terms

Conditions

Chlamydia Infections

Condition Hierarchy (Ancestors)

Chlamydiaceae Infections; Gram-Negative Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections; Sexually Transmitted Diseases, Bacterial; Sexually Transmitted Diseases; Communicable Diseases; Genital Diseases; Urogenital Diseases

Central Study Contacts

Trial Transparency email recommended (Toll free for US & Canada)

CONTACT

800-633-1610; Contact-US@sanofi.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Masking Details: Sentinel Cohorts: modified double-blind * Investigator, participants, and laboratory personnel will be blinded * Clinical site staff preparing / administering the study vaccines will be unblinded * Sponsor study staff involved in the early safety data review (ESDR) will be unblinded at the time of the ESDR Main Cohort: modified double-blind * Investigator, participants, laboratory personnel, and Sponsor study staff will be blinded * Only clinical site staff preparing / administering the study vaccines will be unblinded
• Purpose: PREVENTION
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Sequential (Phase 1) / parallel (Phase 2), dose finding, multi center

Study Record Dates

• First Submitted: March 17, 2025
• First Posted: March 24, 2025
• Study Start: March 27, 2025
• Primary Completion (Estimated): January 3, 2028
• Study Completion (Estimated): January 3, 2028
• Last Updated: April 8, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will share

Locations

AU (7)