Abbisko Therapeutics Co., Ltd. has reported positive preliminary Phase II data for lavengratinib (ABSK061), an investigational oral therapy for achondroplasia, the most common form of dwarfism caused by dysregulated FGFR3 pathway signaling. The early results indicate improved growth velocity in treated children alongside a favorable safety profile.
Achondroplasia results from overactive FGFR3 signaling, which inhibits normal bone development. Lavengratinib is a selective, orally administered small-molecule inhibitor targeting FGFR2 and FGFR3, designed to restore skeletal growth by modulating this pathway.
The ongoing ABSK061-202 trial is a multicenter, open-label, dose-escalation study evaluating once-daily lavengratinib in children aged 3 to 12 years with achondroplasia, with a planned treatment duration of 78 weeks.
In the initial low-dose cohort, seven children aged 6 to 12 years received lavengratinib at 0.064 mg/kg once daily for 27 weeks. Participants achieved a mean annualized height velocity increase of 2.4 cm per year from baseline, with a 100% responder rate—defined as at least a 25% improvement in annualized height velocity. Evaluation of higher-dose cohorts is ongoing.
The treatment was generally well tolerated. No serious adverse events, treatment discontinuations due to adverse events, or class-associated safety concerns—including hyperphosphatemia and corneal toxicity—were observed.
Lavengratinib utilizes Abbisko’s proprietary oral mini-tablet formulation, with tablets under 3 mm in diameter that can be administered with food or liquids, facilitating adherence in pediatric patients.
Preliminary safety reviews across the first three dose cohorts have identified no major concerns. Additional six-month efficacy data from higher-dose cohorts are anticipated by the end of 2026.