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ProQR® Source : ProQR Therapeutics N.V. September 09 , 2026 08:00 ET ProQR Announces First Participant Dosed in Phase 1 Study of AX - 0811 and Virtual Investor and Analyst Educational Event on September 30 , 2026 LEIDEN , Netherlands & CAMBRIDGE , Mass . , Sept. 09 , 2026 ( GLOBE NEWSWIRE ) -- ProQR Therapeutics N.V. ( Nasdaq : PRQR ) ( ProQR ) , a clinical - stage company dedicated to changing lives through transformative RNA therapies based on its proprietary ADAR - mediated Axiomer ™ RNA editing technology platform , today announced that the first participant has been dosed in the Phase 1 clinical trial of AX - 0811 in healthy volunteers . AX - 0811 is ProQR's next - generation , Al - discovered investigational RNA editing oligonucleotide ( EON ) designed to modulate NTCP , with preclinical data demonstrating greater potency and a longer half - life compared with AX - 0810 . AX - 0811 is being developed as a potential disease- modifying treatment for cholestatic liver diseases , including biliary atresia . The Phase 1 study is designed to evaluate the safety , tolerability , pharmacokinetics ( PK ) , and pharmacodynamic ( PD ) biomarkers of AX - 0811 in healthy volunteers and builds on ProQR's clinical experience with AX - 0810 . Phase 1 target engagement data for the first two cohorts are expected in early January 2027 . ProQR will also host a virtual Investor and Analyst educational event : " NTCP Modulation in Biliary Atresia via Liver - Targeted RNA Editing " . The event will take place on September 30 , 2026 beginning at 11am ET , and will feature presentations by ProQR management and Gideon Hirschfield , MA ( Oxon ) , MB BChir ( Cantab ) , FRCP , PhD , Professor of Gastroenterology and Hepatology at the Toronto Centre for Liver Disease . The event will provide an in - depth review of the role of bile acids and NTCP modulation in cholestatic liver disease , with a focus on biliary atresia . ProQR will review the recently reported AX - 0810 Phase 1 target engagement data and discuss the translational rationale and clinical development strategy for NTCP modulation in biliary atresia , including the framework for evaluating upcoming next - generation AX - 0811 Phase 1 data and its potential to treat cholestatic disease .