arGEN-X N.V. (Euronext Brussels: ARGX), a clinical-stage biopharmaceutical company focused on creating and developing differentiated therapeutic antibodies for the treatment of cancer and severe autoimmune diseases, has completed enrolment of the first expansion cohort of 15 patients with CD70-positive hematological malignancies, part of an ongoing open-label Phase 1b trial with ARGX-110, a novel anti-CD70 therapeutic antibody.