Chlamydia Vaccines

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Last reviewed
April 17, 2024
Content Overview
Chlamydia is a common STD among women. The U.S. FDA has not approved a vaccine to prevent chlamydia infection.

Chlamydia Vaccines 2024

The U.S. Food and Drug Administration (FDA), the United Kingdom, and the European Medicines Agency (EMA) have not approved a vaccine to prevent chlamydia infections. However, researchers are processing vaccine candidates in clinical trials in April 2024 targeting Chlamydia trachomatis (CT), the most common bacterial sexually transmitted pathogen.

Chlamydia Vaccine Candidates

Statens Serum Institut adjuvanted vaccine candidate (CTH522) has completed clinical phase Ia and Ib clinical testing in The Lancet Infectious Diseases and Research Square. The vaccine antigen CTH522 is a recombinant, engineered version of the C. trachomatis major outer membrane protein, comprising heterologous immunorepeats from four genital C. trachomatis serovars (D, E, F, and G). In April 2024, CTH522, with CAF01 or CAF09b, was found safe and immunogenic in the EU Horizon Program TRACVAC-funded phase 1 clinical trial. 85 μg CTH522-CAF01 induced robust serum IgG binding titers. Intradermal vaccination conferred systemic IgG neutralization breadth, and topical ocular administration increased ocular IgA formation. 

Sanofi's multi-antigen chlamydia vaccine candidate will move to Phase 1/2 in early 2024.

LinKinVax, linked to the Vaccine Research Institute, is conducting pre-clinical research on the Anti.CD40.chlamydia vaccine candidate.

The UNC Chlamydia Vaccine Initiative is funded by the National Institute of Allergy and Infectious Diseases to accelerate the development of a novel vaccine that prevents CT ascension in the female genital tract, eliminating CT-associated PID and infertility.

A safe and effective multi-epitope vaccine was designed using an immunoinformatics approach to prevent C. pneumoniae infection. As of September 12, 2023, the study's results provided novel strategies for developing C. pneumoniae vaccines; however, future experimental validation of this vaccine candidate is needed to determine its efficacy, effectiveness, and safety.

Chlamydia Tests

The U.S. FDA granted marketing authorization to LetsGetChecked for the Simple 2 Test on November 15, 2023. This is the first diagnostic test for Chlamydia and gonorrhea with at-home sample collection to be granted marketing authorization. A new WHO report on the Diagnostics Landscape for Sexually Transmitted (July 2023) Infections highlights diagnostics available to support scale-up of screening for STIs, including Chlamydia.

Chlamydia Overview

On April 21, 2023, the U.S. Centers for Disease Control and Prevention (CDC) announced Chlamydia was the most common sexually transmitted disease (STD) in the U.S. in 2021, with 1,644,416 cases, a 3.9% increase compared with 2020, with 58% of all chlamydia cases occurring among people aged 15 to 24 years. If undetected or left untreated, the STD Chlamydia represents a significant cause of pelvic inflammatory disease and infertility in women. In the United Kingdom, chlamydia diagnoses (all ages) increased by 24.3% to 199,233 in 2022.

Chlamydia News

April 11, 2024 - The Lancet published an Editorial - Immunological responses in a Chlamydia trachomatis vaccine trial.

May 8, 2023 - Australian scientists have begun vaccinating wild koalas against Chlamydia in an ambitious field trial in New South Wales. A Chlamydia vaccine for koalas has shown promise for replacing antibiotic treatment in mild ocular Chlamydia disease. 

April 12, 2023 - Blue Water Vaccines Inc. announced the signing of a Sponsored Research Agreement with The University of Texas Health Science Center at San Antonio to fund a non-human primate study to evaluate the efficacy of BWV-401, a live attenuated, orally delivered Chlamydia vaccine. In this new effort, BWV will fund an NHP study to evaluate the effectiveness of BWV-401 further and provide additional support for development towards human clinical trials.

April 6, 2023—The NEJM journal published the findings from Original Research, which disclosed that the incidence of Chlamydia disease was two-thirds lower following treatment with doxycycline compared to standard care.

March 20, 2023 - Kathryn Frietze, Ph.D., an assistant professor in The University of New Mexico's Department of Molecular Genetics & Microbiology, received a five-year grant from the U.S. NIH for $250,000 per year to support efforts to develop a vaccine for Chlamydia.

February 20, 2023 - Researchers from the University of Washington, Kenya Medical Research Institute, and Hennepin Healthcare Research Institute announced results from a clinical trial demonstrating that doxycycline taken after sex does not prevent bacterial sexually transmitted infections (Chlamydia or gonorrhea) among women. 

May 30, 2022 - The journal Vaccines published: Epitope-Based Vaccines against the Chlamydia trachomatis Major Outer Membrane Protein Variable Domain 4 Elicit Protection in Mice. Immunization with these MS2 VLPs protected from vaginal Chlamydia infection in a murine challenge model. These data suggest that short peptide epitopes targeting the MOMP-VD4 could be appropriate for Ct vaccine design when displayed on an immunogenic bacteriophage VLP vaccine platform.

January 12, 2022 - The journal Vaccines published: Immunogenicity and Protective Capacity of a Virus-like Particle Vaccine against Chlamydia trachomatis Type 3 Secretion System Tip Protein, CT584. These data demonstrate the potential for antibodies against the T3SS to contribute to protection against C. trachomatis and the value of VLPs as a novel platform for C. trachomatis vaccines.

April 28, 2021 - Chlamydia trachomatis vaccines for genital infections: where are we, and how far is there to go? The first Phase, one clinical trial of a C. trachomatis vaccine to protect against genital infections, was completed.