CIT-013

Randomized multi-center study designed to assess the efficacy, safety, and tolerability of CIT-013 in patients with moderately active rheumatoid arthritis 2 September 2025 – Citryll, a biotech company pioneering a transformative approach to treating immune-mediated inflammatory diseases by targeting Neutrophil Extracellular Traps (NETs), today announces that the first patient has been successfully dosed in its Phase IIa clinical trial “Citydream”. The trial will evaluate CIT-013, a first-in-class monoclonal antibody, in patients with moderately active rheumatoid arthritis (RA). To support the advancement of the clinical investigations and broader strategy, Citryll has established an RA Clinical Advisory Board, comprising leading experts in the field to provide strategic and scientific guidance throughout the clinical development of CIT-013 in RA and other autoimmune diseases. RA is a chronic autoimmune disease characterized by inflammation of the joints. Its hallmark symptoms include joint pain, stiffness and swelling, resulting in reduced mobility and loss of joint integrity, severely impacting the quality of life. Despite significant advances in treatment options, there remains a high medical unmet need, with a high proportion of patients unable to maintain adequate disease control through current therapies. “The dosing of the first patient in our Phase IIa trial marks a significant milestone in Citryll’s mission to transform the treatment landscape for patients suffering from immune-mediated inflammatory conditions such as rheumatoid arthritis,” said Maarten Kraan, Chief Medical Officer of Citryll. “With a compelling preclinical and clinical data set together with strong backing from a top-tier investor syndicate we are proud to advance our lead programme into Phase 2 trials. Citydream represents an important step in validating the potential of CIT-013 in rheumatoid arthritis and we remain deeply committed to bringing this promising therapy to patients.” “The initiation of the Phase IIa trial of CIT-013 is a critical step in advancing what we believe to be a first-in-class therapeutic approach,” said Rogier Thurlings, MD, PhD, Lead Investigator of Citydream. “By targeting NETs, CIT-013 represents a novel and potentially disease-modifying approach to RA as well as other immune mediated conditions. This mechanism offers a fundamentally different mode of action from current therapies, which often fail to achieve sustained disease control in patients.” Citydream is a Phase IIa, randomized, double-blind, placebo-controlled, multi-center study conducted across multiple sites in Europe. The study is designed to assess the efficacy, safety, and tolerability of CIT-013 in patients with moderately active RA. The trial will enroll 88 patients who will undergo a 6-week treatment period, followed by an open-label extension phase to further assess safety and efficacy. Citydream follows the successful completion of Citryll’s first-in-human Phase 1 study, which included successful repeat dosing of rheumatoid arthritis (RA) patients as well as an €85 million Series B fundraise. An additional Phase IIa trial is also planned in hidradenitis suppurativa (HS) starting later this year. CIT-013 is Citryll’s first-in-class monoclonal antibody targeting Neutrophil Extracellular Traps (NETs), a key driver of inflammation in RA and other immune-mediated diseases, which has yet to be addressed therapeutically. It has a unique dual mechanism of action, which enhances the clearance of existing NETs and inhibits the formation of new NETs. CIT-013 is highly selective for its epitope, minimising off-target effects and representing a potentially transformative therapeutic strategy, going beyond individual pathway management and symptom treatment. Citryll is pioneering a transformative approach to treating inflammatory diseases by targeting Neutrophil Extracellular Traps (NETs), a fundamental component of the inflammatory process that has yet to be addressed therapeutically. Citryll is developing the first NET-targeting therapy and potentially creating a new class of therapeutics with broad applications across immune-mediated inflammatory diseases. Our lead asset, CIT-013, is a first-in-class monoclonal antibody with a unique dual mechanism of action: it enhances the clearance of existing NETs and inhibits the formation of new NETs. By addressing this key driver of inflammation, CIT-013 has the potential to offer a differentiated and comprehensive treatment option for conditions such as rheumatoid arthritis and hidradenitis suppurativa, where current therapies often fall short of providing adequate disease control. The content above comes from the network. if any infringement, please contact us to modify.

CITRYLL ANNOUNCES FORMATION OF SCIENTIFIC ADVISORY BOARD Board comprises world-renowned experts in biology, immunology and pathology Oss, Netherlands – 24 July 2025 – Citryll, a biotech company pioneering a transformative approach to treating immune-mediated inflammatory diseases by targeting Neutrophil Extracellular Traps (NETs), today announces the formation of its Scientific Advisory Board (SAB). The Board will provide strategic guidance and scientific insight as Citryll advances the development of CIT-013, its first-in-class monoclonal antibody, through the clinic. The SAB brings together internationally recognised experts in NET biology, pre-clinical development, and immunology. The founding members include Dr. Tim Hammond, Professor John Hamilton, Dr. Christian Lood and Professor Paul Kubes. “We are honoured to welcome this distinguished group of experts to Citryll’s Scientific Advisory Board,” said Eric Meldrum, Chief Scientific Officer of Citryll. “Their combined expertise will be invaluable as we advance CIT-013 in ongoing trials in rheumatoid arthritis and hidradenitis suppurativa. With their guidance, we aim to unlock the full therapeutic potential of targeting extracellular traps in a range of inflammatory diseases. This is an important step in strengthening our broader advisory network, as we also work to build a Clinical Advisory Board to support our next stage of clinical development.” Members of Citryll’s Scientific Advisory Board include: Dr. Tim Hammond, PhD Tim brings over 35 years of experience in pharmaceutical drug discovery and development. He is currently Head of Safety at various companies and was formerly Vice President of Safety Assessment in the UK for AstraZeneca. He has been an independent consultant since 2012. Tim is a past President of the British Toxicology Society, is a Fellow of the Royal College of Pathologists, is a member of the American Society of Toxicology and was a founding member of the International Safety Pharmacology Society, which awarded him the Distinguished Scientist Award in 2007. He holds a PhD in Pharmacology and Toxicology from the University of Birmingham and an Honorary Professorship from the University of Liverpool. Professor John Hamilton, PhD John is internationally recognised for his expertise in macrophage biology and inflammation, with his research significantly contributing to the understanding of inflammatory mechanisms in diseases such as rheumatoid arthritis. He has received numerous honours, including the Australian Rheumatology Association Distinguished Service Medal, the American College of Rheumatology Distinguished Basic Investigator Award, and the International Association of Inflammation Societies Lifetime Achievement Award. He is a Professor in the Department of Medicine at the University of Melbourne and a Fellow of the Australian Academy of Science. He holds a PhD in Chemistry from the University of Melbourne. Dr. Christian Lood, PhD Christian is a leading researcher in neutrophil function, NET formation, and the role of innate immunity in autoimmune diseases such as systemic lupus erythematosus. His work has provided critical insights into how NETs contribute to autoimmune pathology and therapeutic intervention opportunities. He is currently an Associate Professor, Division of Rheumatology at the University of Washington with a focus in neutrophil biology in inflammatory and autoimmune conditions. He holds a PhD in Biomedicine from Lund University. Professor Paul Kubes, PhD Professor Paul Kubes is known internationally for his expertise in leukocyte recruitment and inflammation, with significant contributions to understanding immune cell function in inflammatory disease and tissue repair. He is a professor at Queen’s University, where he recently accepted a Canada Excellence Research Chair. Prior to this, he was a Professor at the University of Calgary Cumming School of Medicine and the Founding Director of the Snyder Institute for Chronic Disease for 15 years. He also holds a Canada Research Chair in Leukocyte Recruitment in Inflammatory Disease. Professor Paul Kubes has received numerous awards, including the CIHR Investigator of the Year and the Henry Friesen Award, and has published in leading journals such as Cell, Science, and Nature. He holds a B.Sc. (Honours) in Biological Sciences, an M.S. in Physiology, and a Ph.D. in Physiology from Queen’s University. -ENDS- About Citryll Citryll is pioneering a transformative approach to treating inflammatory diseases by targeting Neutrophil Extracellular Traps (NETs), a fundamental component of the inflammatory process that has yet to be addressed therapeutically. Citryll is developing the first NET-targeting therapy and potentially creating a new class of therapeutics with broad applications across immune-mediated inflammatory diseases. Our lead asset, CIT-013, is a first-in-class monoclonal antibody with a unique dual mechanism of action: it enhances the clearance of existing NETs and inhibits the formation of new NETs. By addressing this key driver of inflammation, CIT-013 has the potential to offer a differentiated and comprehensive treatment option for conditions such as rheumatoid arthritis and hidradenitis suppurativa, where current therapies often fall short of providing adequate disease control. Contacts CitryllSjoerd van Gorp, COOEmail: info@citryll.com Citryll Media ContactsICR HealthcareAmber Fennell, Stephanie Cuthbert, Lucy FeatherstoneEmail: citryll@icrinc.com