Actio Biosciences has launched a Phase 1b/2 clinical trial of ABS-1230, an investigational precision medicine for KCNT1-related epilepsy.
KCNT1-related epilepsy is a rare, severe and often fatal paediatric developmental epileptic encephalopathy caused by genetic changes affecting the KCNT1 potassium ion channel.
ABS-1230 is being developed as an orally available small molecule inhibitor designed to target the underlying genetic mechanism of the disease.
The KYRON trial will evaluate the safety, tolerability and pharmacokinetics of ABS-1230 in children and young adults aged one month to 21 years with KCNT1-related epilepsy.
The treatment will be administered orally or through a feeding tube.
The study will also assess the effects of ABS-1230 on seizure activity and neurodevelopmental outcomes.
Actio said ABS-1230 has also been accepted into the US Food and Drug Administration’s Rare Disease Evidence Principles process.
The framework is designed to support the development of therapies for ultra-rare, genetically defined diseases by enabling early alignment with the FDA on how to demonstrate substantial evidence of effectiveness.
David Goldstein, CEO of Actio Biosciences, said: “The initiation of the KYRON trial marks a pivotal moment in our mission to bring a potentially disease-modifying, targeted therapy to children living with KCNT1-related epilepsy and their families.
“ABS-1230 is an investigational, precision-designed inhibitor of the overactive KCNT1 potassium ion channel that directly targets the underlying genetic driver of disease, and our preclinical and Phase 1a data reinforce our confidence in its potential to meaningfully reduce seizure burden.
“Acceptance into the FDA’s RDEP process is especially significant, as it provides a collaborative regulatory framework tailored to ultra-rare genetic diseases and may help clarify the path to bringing ABS-1230 to patients who urgently need new treatment options.”
In a Phase 1a trial involving healthy volunteers, all doses of ABS-1230, including multiple 20mg doses, were well tolerated, with no serious adverse events reported.
The KYRON trial will include three parts. The first is a 12-week open-label, single-arm treatment study of ABS-1230.
The second is a 12-week randomised, double-blind, placebo-controlled study in additional participants.
The third is an optional open-label long-term extension for participants who complete part one or part two.
Initial enrolment will include older children and young adults. Progression to younger children and infants will follow evaluation of safety, tolerability and confirmation of an appropriate dose in each age group.
Justin West, co-founder and president of the KCNT1 Epilepsy Foundation, said: “For families in this community, including mine, the focus each day is simple and urgent: keeping our children alive.
“Relentless seizures, medical fragility and profound developmental challenges define daily life.
“The start of Actio’s KYRON trial represents real progress and renewed hope for families who have waited far too long for a treatment designed specifically for KCNT1-related epilepsy.
“We are deeply grateful to the patients, caregivers and investigators who are driving this work forward, and we are encouraged by what this programme could mean for reducing seizure burden and improving quality of life for these children.”
The FDA’s Rare Disease Evidence Principles process was established in September 2025 to support potential approvals for drugs targeting rare diseases with very small patient populations, significant unmet need and a known genetic defect driving disease.
Under the framework, substantial evidence of effectiveness may generally be established through one adequate and well-controlled study, including a single-arm trial, alongside strong confirmatory evidence supporting the treatment effect.