Prof. Dr. Ahmet Özen
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In 2017, Dr. Özen discovered CD55 deficiency (CHAPLE disease), linking CD55 mutations to congenital protein-losing enteropathy due to primary intestinal lymphangiectasia and to deep-seated thrombosis. He established complement dysregulation as the core disease mechanism and a therapeutically actionable target. In 2021, his work showed marked clinical benefit with the complement inhibitor eculizumab and combined proteomic, microbiome, and pharmacologic analyses to deepen understanding of disease biology. He then led the global development of pozelimab (Veopoz), a C5-blocking monoclonal antibody that became the first targeted therapy for CHAPLE and received FDA approval in 2023. This discovery-to-therapy pathway—completed in roughly seven years and driven from Turkey—catalyzed international collaboration and positioned him as a global authority in congenital PLE, including an invited genomics-era framework review in NEJM (2023). His contributions have broadened the field to complement-mediated lymphatic and vascular disorders (including an invited JACI article in 2025) and to additional monogenic IBD phenotypes such as IRHOM2, ST6GALNAC1, PIK3R1, and IL-37 deficiencies. His honors include the EFIS Publication Award (2021), the TÜSEB Aziz Sancar Distinguished Service Award (2022), the Eastern Star Award (2024), and the TÜBİTAK Science Award (Health) in 2025.