Chlamydia mRNA vaccine for young adults

A Phase 1/2, Randomized, Placebo-controlled, Multi-arm, Dose-finding Study to Evaluate the Safety, Immunogenicity, and Efficacy of a Chlamydia Trachomatis mRNA Vaccine Candidate in Adults Aged 18 to 29 Years

This study is testing a new Chlamydia mRNA vaccine in young adults aged 18 to 29 to see if it is safe and effective.

Quick facts

• Phase: Phase1; Phase2
• Study type: Interventional
• Enrollment: 1560 (estimated)
• Ages: 18 Years to 29 Years
• Sex: All
• Sponsor: Sanofi (Industry-sponsored)
• Drugs / interventions: chemotherapy, radiation, prednisone
• Locations: 7 sites (Bruce, Australian Capital Territory and 6 other locations)
• Trial ID: NCT06891417 on ClinicalTrials.gov

What this trial studies

This study evaluates the safety, efficacy, and immunogenicity of a Chlamydia mRNA vaccine in adults aged 18 to 29 years. Participants will receive different dose levels of the vaccine, with a focus on assessing safety through three Sentinel Cohorts before moving to a Main Cohort. The study involves follow-up for up to 12 months after the last vaccine administration, making the total duration of participation approximately 18 months.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 to 29 with specific sexual health risk factors, such as new or multiple sex partners or a history of sexually transmitted infections.

Not a fit: Patients who are not sexually active or do not meet the eligibility criteria related to sexual health risk factors may not benefit from this study.

Why it matters

Potential benefit: If successful, this vaccine could significantly reduce the incidence of Chlamydia infections among young adults.

How similar studies have performed: While there have been studies on vaccines for other sexually transmitted infections, this specific mRNA approach for Chlamydia is novel and has not been extensively tested.

Eligibility criteria

Inclusion Criteria:

* Aged 18 to 29 years on the day of inclusion
* 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.

OR

• 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

Exclusion Criteria:

* 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
* Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, 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

Note: The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Where this trial is running

Bruce, Australian Capital Territory and 6 other locations

• Investigational Site Number : 0360002 — Bruce, Australian Capital Territory, Australia (Recruiting)
• Investigational Site Number : 0360006 — Maroubra, New South Wales, Australia (Recruiting)
• Investigational Site Number : 0360005 — Sydney, New South Wales, Australia (Recruiting)
• Investigational Site Number : 0360001 — Albion, Queensland, Australia (Recruiting)
• Investigational Site Number : 0360004 — Morayfield, Queensland, Australia (Recruiting)
• Investigational Site Number : 0360003 — Southport, Queensland, Australia (Recruiting)
• Investigational Site Number : 0360010 — Melbourne, Victoria, Australia (Recruiting)

Study contacts

• Study coordinator: Trial Transparency email recommended (Toll free for US & Canada)

Conditions Chlamydia Trachomatis Immunization; Chlamydia