Pharmaceutical company Servier committed a $450 million investment in Kaerus' therapy targeting Fragile X Syndrome.

Servier Acquires Fragile X Syndrome Therapy Candidate from Kaerus Bioscience

In a significant development, French pharmaceutical company Servier has announced an agreement to acquire KER-0193, a potential therapy for fragile X syndrome, from Kaerus Bioscience. The specific terms of the deal were not provided.

KER-0193, an investigational small-molecule drug, has shown promise in preclinical studies, improving behavioural, sensory, and cognitive symptoms related to fragile X syndrome. The drug is designed to be orally available and has received both orphan drug and rare pediatric drug designations from the FDA for fragile X syndrome.

Servier's acquisition of KER-0193 comes after a recent partnership with IDEAYA Biosciences, where Servier invested $210 million upfront for the investigational kinase inhibitor darovasertib for uveal melanoma. This partnership includes up to $210 million in commercial milestones, up to $100 million in regulatory milestones, and royalties.

Meanwhile, Servier has also entered a deal with Black Diamond, licensing BDTX-4933 for $70 million upfront and promising $710 million in development and sales milestones, with royalties included. However, BDTX-4933, which is in early-stage development for solid tumors, was deprioritized in October 2024 due to cash constraints.

Kaerus completed a Phase I study of KER-0193 in March, and under the agreement with Servier, Kaerus could receive up to $450 million. The planned Phase II study by Servier for KER-0193 is expected to start in the first half of 2026, with trials taking place in both America and Europe.

Fragile X syndrome is a rare genetic condition affecting approximately 1 in 7,000 males and 1 in 11,000 females worldwide. Characterised by cognitive and developmental delays, crossed eyes, behavioural problems, and mental health conditions such as anxiety and depression, the condition can significantly impact the quality of life for those affected.

The underlying genetic cause of fragile X syndrome is associated with impaired BK channel function. KER-0193 is a modulator of BK channels, calcium-activated ion channels, which makes it a promising candidate for treating fragile X syndrome.

As Servier moves forward with the development of KER-0193, the company is hopeful that this potential therapy will bring new hope to those affected by fragile X syndrome. The acquisition of KER-0193 from Kaerus Bioscience marks an important step in the journey towards finding a treatment for this debilitating condition.