Kaerus Bioscience secures orphan drug designation for fragile x syndrome treatment

FDA recognises KER-0193 as a potential therapy for rare paediatric disease

Kaerus Bioscience has received orphan drug and rare paediatric drug designations from the FDA for KER-0193, its lead candidate targeting fragile x syndrome (FXS). The announcement follows a successful phase 1 trial confirming the drug’s safety and promising pharmacokinetics.

FXS is the most common cause of inherited autism and intellectual disability, affecting approximately 1 in 7,000 males and 1 in 11,000 females. There are currently no approved treatments for the condition.

Dr Robert Ring, CEO of Kaerus Bioscience, said: “The FDA’s granting of orphan drug designation and rare paediatric drug designation for KER-0193 is an important step towards our objective of delivering an effective treatment for people with fragile x syndrome.”

KER-0193 is a novel, orally bioavailable small molecule designed to address hyper-excitability of brain function associated with FXS. It targets BK channels, which regulate excitability across the nervous system, and whose reduced function is directly linked to the condition.

A pre-planned sub-study in the phase 1 trial investigated KER-0193’s effects on brain activity using electroencephalography. The results confirmed the drug enters the brain and produces pharmacodynamic effects in regions often implicated in FXS patients, replicating findings from preclinical animal studies.

Kaerus believes KER-0193 has potential to address the diverse behavioural, sensory and cognitive challenges affecting individuals with FXS. The company is finalising preparations for a phase 2 proof-of-concept study.

Beyond FXS, reduced BK channel activity has been linked to several other neurological conditions, including epilepsy and rare genetic epileptic encephalopathies. Kaerus is exploring opportunities to expand the therapeutic potential of its BK modulator platform to these indications.