Sylvain Chemtob and France Côté
Credit: Véronique Lavoie, CHU Sainte-Justine
Every year, 15 million babies are born prematurely around the world. For these children, each additional day in the womb can have a decisive impact on their health and quality of life. Now scientists are proposing an effective and affordable solution to prevent premature births.
Led by Universite de Montréal PhD candidate France Côté and supervised by UdeM pharmacology professor Sylvain Chemtob, their study was published earlier this month in EMBO Molecular Medicine.
The research was 15 years in the making and builds on the pioneering discoveries of UdeM biochemist Christiane Quiniou.
Quiniou was the first to design peptides targeting the interleukin-6 (IL-6) receptor, a cytokine that's essential to innate immunity and that helps trigger premature labor. The UdeM scientists developed a peptide called HSJ633 that's a game-changer in how prematurity is managed.
"This peptide is unique: it temporarily inhibits the harmful inflammatory effects of IL-6 while preserving its protective functions, such as cellular defense - it's a real breakthrough," said Chemtob," a neonatologist at the Azrieli Research Centre of the CHU Sainte-Justine.
Easy to produce
Conventional treatments, which aim to slow uterine contractions, are often non-specific and associated with side effects for both mother and fetus. By contrast, HSJ633 is a molecule that is easy to produce, stable, and affordable.
It acts directly on uteroplacental inflammation-the main trigger of premature labor. A treatment could cost significantly less than the anti-IL-6 antibodies currently used in clinical settings (for other medical conditions), making HSJ633 a very promising and safer alternative.
"The idea of targeting IL-6 came from our work on inflammation," Quinio recalled. "When I developed those first peptides, I hoped they might one day make a difference. Seeing that intuition materialize in HSJ633 is deeply rewarding."
Initially designed for other inflammatory diseases, the peptide has shown remarkable potential in preventing prematurity in mice. "This small peptide does exactly what we hoped: it reduces inflammation without harming fetal development," said Côté.
Validated in mice
The effects of HSJ633 were validated in preclinical models (in mice) simulating systemic inflammation. Administered before or after the onset of labor, it prolonged gestation by several days while reducing damage to vital organs such as the lungs and intestines of newborns.
That kind of organ protection is highly desirable and absent in current treatments for prematurity. The results observed with HSJ633 suggest strong and lasting therapeutic potential, the scientists believe.
They'd now like to set up a clinical study in humans. "We hope HSJ633 will become a key tool in preventing prematurity - it's a concrete response to a global issue," said Chemtob.
"It's rare for an innovation to combine so much scientific, clinical, and human potential. Seizing this opportunity is a decisive step for the health of newborns and their families, here and around the world."
About this study
"A novel modulator of IL-6R prevents inflammation-induced preterm birth and improves newborn outcome," by France Côté et al., was published July 3, 2025 in EMBO Molecular Medicine.
