Sanofi Accelerates Chlamydia Prevention with Fast Tracked mRNA Vaccine

Sanofi Accelerates Chlamydia Prevention with Fast Tracked mRNA Vaccine

(IN BRIEF) Sanofi’s mRNA vaccine candidate for chlamydia has been granted fast track designation by the US FDA, reflecting its promising potential to address a significant public health issue. Designed to protect against primary and recurrent infections caused by Chlamydia trachomatis, the vaccine is set to undergo a phase 1/2 clinical trial in adults aged 18 to 29, with the study scheduled to begin shortly. This initiative is driven by the urgent need to prevent the long-term complications of chlamydia infections, such as pelvic inflammatory disease, pregnancy complications, and infertility, particularly given that over 80% of cases are asymptomatic. The development effort is part of a collaborative partnership through the Translational Science Hub, uniting researchers from Australia and Sanofi’s international teams, and aims to make chlamydia a preventable condition through innovative vaccination strategies.

(PRESS RELEASE) PARIS, 26-Mar-2025 — /EuropaWire/ — The US Food and Drug Administration has recently granted fast track designation to Sanofi’s innovative mRNA vaccine candidate aimed at preventing chlamydia infections. This decision comes in response to the vaccine’s potential to tackle a serious public health issue by addressing an unmet need for effective prevention measures against chlamydia—a common bacterial infection known to trigger pelvic inflammatory disease, pregnancy complications, and infertility in women.

Sanofi’s chlamydia vaccine candidate is specifically engineered to guard against both primary genital tract infections and subsequent reinfections caused by the bacterium Chlamydia trachomatis. Building on encouraging outcomes from a robust pre-clinical program, the company is preparing to launch a phase 1/2 randomized clinical study. This trial will assess both the immunogenicity and safety of the vaccine in healthy adults aged 18 to 29, with the study set to commence in the coming days.

Jean-François Toussaint, Global Head of Vaccines R&D, commented, “Millions of people currently live with undiagnosed chlamydia, including cases where no symptoms are present but severe long-term health effects can develop if left untreated. With antibiotics falling short in curbing the rising infection rates, our program is dedicated to making chlamydia a preventable disease through vaccination.”

Chlamydia, transmitted by Chlamydia trachomatis, remains a prevalent threat to reproductive health. In 2020 alone, an estimated 129 million adults between the ages of 15 and 49 were affected worldwide, with the highest incidence noted among adolescents and young adults. Although treatable with antibiotics when detected, the asymptomatic nature of more than 80% of cases often results in missed diagnoses, prolonged infection, and unintended transmission. Existing prevention strategies have not been sufficient to stem the tide of infections, underscoring the critical need for a preventive vaccine.

This vaccine development effort is part of the broader Translational Science Hub initiative, a collaborative partnership that brings together leading researchers from the Queensland Government, Griffith University, and the University of Queensland with Sanofi’s teams in France and the United States. This alliance aims to accelerate the translation of cutting-edge scientific research into tangible public health solutions.

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Sandrine Guendoul | +33 6 25 09 14 25 | sandrine.guendoul@sanofi.com
Evan Berland | +1 215 432 0234 | evan.berland@sanofi.com
Nicolas Obrist | +33 6 77 21 27 55 | nicolas.obrist@sanofi.com
Léo Le Bourhis | +33 6 75 06 43 81 | leo.lebourhis@sanofi.com
Victor Rouault | +33 6 70 93 71 40 | victor.rouault@sanofi.com
Timothy Gilbert | +1 516 521 2929 | timothy.gilbert@sanofi.com

Investor Relations
Thomas Kudsk Larsen |+44 7545 513 693 | thomas.larsen@sanofi.com
Alizé Kaisserian | +33 6 47 04 12 11 | alize.kaisserian@sanofi.com
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Yun Li |+33 6 84 00 90 72 | yun.li3@sanofi.com

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SOURCE: Sanofi