Actio Biosciences Announces Initiation of KYRON Phase 1b/2 Trial of ABS-1230 for the Treatment of KCNT1-Related Epilepsy and Acceptance into FDA’s Rare Disease Evidence Principles Process

Actio launches dedicated patient resource to support families seeking information about the KYRON clinical trial at ActioTrials.com

SAN DIEGO--(BUSINESS WIRE)--Actio Biosciences, a clinical-stage biotechnology company advancing the translation of genetic insights into novel precision medicines, today announced the initiation of the KYRON Phase 1b/2 clinical trial of ABS-1230 for the treatment of KCNT1-related epilepsy, a rare, severe and often fatal pediatric developmental epileptic encephalopathy. ABS-1230 is designed to be a potent and selective orally available small molecule KCNT1 inhibitor that addresses the underlying genetic mechanism of disease.

In addition, ABS-1230 for the treatment of KCNT1-related epilepsy has been accepted into the FDA’s Rare Disease Evidence Principles (RDEP) process, a framework designed to facilitate development of certain therapies for ultra-rare, genetically defined diseases by aligning early with FDA on approaches to demonstrate substantial evidence of effectiveness.

“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,” said David Goldstein, Ph.D., CEO of Actio Biosciences. “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.”

“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,” said Justin West, M.D., co-founder and president of the KCNT1 Epilepsy Foundation. “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 program could mean for reducing seizure burden and improving quality of life for these children.”

In the Phase 1a healthy volunteer trial, all doses of ABS-1230, including multiple doses of 20 mg, were well tolerated with no serious adverse events reported.

The KYRON Phase 1b/2 study will evaluate the safety, tolerability and pharmacokinetics of ABS-1230 administered orally or via feeding tube in children and young adults aged one month through 21 years with KCNT1-related epilepsy. This study will also assess the effects of ABS-1230 on seizure activity and neurodevelopmental outcomes. The trial consists of three parts:

• Part 1: a 12-week open-label single-arm treatment study of ABS-1230;
• Part 2: a 12-week randomized, double-blind, placebo-controlled study in additional participants; and
• Part 3: an optional open-label long-term extension for participants completing Part 1 or 2.

Initial enrollment will include older children and young adults. Progression to younger children and infants will be determined following evaluation of safety, tolerability and confirmation of an appropriate dose in each age group.

For additional information about trial, eligibility and trial locations, please visit ActioTrials.com.

About the Rare Disease Evidence Principles Process

The Rare Disease Evidence Principles Process (RDEP) process was established in September 2025 to facilitate the approval of drugs to treat rare diseases with very small patient populations with significant unmet medical need and with a known genetic defect that is the major driver of the pathophysiology. Eligible investigative therapies must specifically address the genetic defect in question and target a very small, rare disease population or subpopulation facing rapid deterioration in function leading to disability or death, for whom no adequate alternative therapies exist. For investigational therapies admitted into the RDEP framework, FDA expects that substantial evidence of effectiveness may generally be established based on one adequate and well-controlled study, including a single-arm trial, together with strong confirmatory evidence supporting the drug’s treatment effect.

About KCNT1-Related Epilepsy

KCNT1-related epilepsy is a rare and often fatal pediatric epileptic encephalopathy. Patients with KCNT1-related epilepsy experience frequent treatment-resistant seizures that typically begin in early infancy and are accompanied by profound developmental delays and neurological impairments. General antiepileptic drugs have limited benefit in patients with this genetic epilepsy and are often associated with debilitating side effects.

About ABS-1230

ABS-1230 is designed to be a potent and selective orally available small molecule KCNT1 inhibitor for the treatment of KCNT1-related epilepsy. In preclinical studies, ABS-1230 inhibited all tested pathogenic mutations in the KCNT1 gene, indicating potential to treat all patients with KCNT1-related epilepsy. ABS-1230 has the potential to provide patients with the convenience of an at-home, orally administered therapy. ABS-1230 has FDA Fast Track, Rare Pediatric Disease and Orphan Drug designations and has been accepted into the Rare Disease Evidence Principles process.

About Actio Biosciences

Actio Biosciences is a clinical-stage biotechnology company advancing the translation of genetic insights into novel small molecule precision medicines. The company applies deep expertise in Mendelian genetics, drug discovery and data science to identify targets whose biology underlies rare diseases with high unmet need and hold promise for the treatment of more prevalent indications. By precisely targeting the root causes of rare diseases, Actio generates biological insights to enable expansion of development into more prevalent indications.

The company is advancing two clinical-stage programs: ABS-1230 for the treatment of KCNT1-related epilepsy, and ABS-0871 for the treatment of Charcot-Marie-Tooth disease type 2C including other TRPV4-related neuromuscular disorders (collectively, CMT2C). Actio will also pursue development of both programs in more prevalent indications such as additional genetic epilepsies for ABS-1230 and overactive bladder for ABS-0871. In addition, the company has launched a third program for a rare genetic epilepsy as well as a common central nervous system disorder. For more information, please visit ActioBiosciences.com and follow the company on LinkedIn and X.