SHANGHAI, Sept. 20, 2026 /PRNewswire/ -- 21 September 2026 (Beijing time), Abbisko Therapeutics Co., Ltd. ("Abbisko Therapeutics" hereafter, HKEX code: 02256.HK) today announced positive preliminary efficacy results from the Phase II clinical study of lavengratinib (ABSK061), a selective orally available small-molecule FGFR2/3 inhibitor, in children with achondroplasia (ACH). In the first and lowest dose cohort of 0.064mg/kg QD, children aged 6 years and older with ACH who received lavengratinib for 27 weeks achieved a mean increase of +2.4 cm/year in annualized height velocity (AHV) from baseline, with a 100% responder rate*. Lavengratinib was well-tolerated with no observed FGFR1 or FGFR2-associated adverse events (AEs).
ABSK061-202 is a Phase II, multicenter, open-label, dose-escalation study designed to evaluate the safety and efficacy of lavengratinib (once daily, orally administered) in children aged 3 to 12 years with ACH. All participants will receive lavengratinib for a planned treatment duration of 78 weeks. To date, all seven participants aged 6 to 12 years in cohort 1 have completed six months of treatment and achieved encouraging preliminary results:
- Preliminary data demonstrate positive signals for growth promotion. At Week 27, the seven participants in the first and lowest dose cohort (0.064 mg/kg, once daily) achieved a mean improvement of +2.4 cm/year in AHV from baseline, with a responder rate* of 100%. Participants enrolled in higher dose cohorts are currently ongoing treatment.
- Overall safety and tolerability were favorable. To date, no serious adverse events (SAEs) or treatment discontinuations due to AEs have been reported. No specific safety risks associated with FGFR pathway inhibition have been observed to date, including FGFR1 or FGFR2-associated AEs such as hyperphosphatemia and corneal toxicity.
- Lavengratinib leverages Abbisko's unique oral mini-tablet formulation. Abbisko's unique mini-tablet formulation, with each tablet being less than 3mm in diameter as compared to conventional tablets ~8-10mm in diameter, allows for easy administration with children. Such mini-tablets can be conveniently administered with food and drink.
The ABSK061-202 study has successfully completed the preliminary safety evaluation of the first three dose cohorts, with no safety concerns identified to date. Six-month efficacy and safety results are expected by the end of 2026, providing further evidence to support the evaluation of the clinical potential of lavengratinib in children with ACH.
*Responder is defined as a participant achieving an =25% improvement in AHV from baseline.
About Lavengratinib (ABSK061)
Lavengratinib is a novel, orally bioavailable, highly potent and selective small molecule inhibitor of FGFR2 and FGFR3 independently discovered and wholly-owned by Abbisko Therapeutics. It is the first FGFR2/3 inhibitor to enter clinical trials globally. First-generation pan-FGFR inhibitors demonstrated clinical efficacy in multiple tumors carrying FGFR2/3 variants and have steadily gained regulatory approval globally. However, the therapeutic window of pan-FGFRs and their clinical efficacy have been limited by side effects associated with FGFR1 inhibition. By reducing FGFR1 activity while maintaining potency against FGFR2 and FGFR3, lavengratinib is expected to achieve a wider therapeutic window with improved clinical efficacy as a new-generation of FGFR inhibitors. lavengratinib for the treatment of achondroplasia has received both Rare Pediatric Disease Designation (RPDD) and Orphan Drug Designation (ODD) from the U.S. Food and Drug Administration (FDA), and its Phase II clinical trial is currently ongoing.
SOURCE Abbisko
