argenx Moves Forward with Clinical Trials Of ARGX-119 For Treating Congenital Myasthenic Syndromes

argenx SE, a global immunology company focused on treating severe autoimmune diseases, has announced plans to move forward with a registrational study of ARGX-119, its first-in-class agonist antibody targeting muscle-specific kinase (MuSK). This decision follows the review of topline results from a Phase 1b clinical trial in patients with congenital myasthenic syndromes (CMS). ARGX-119 showed a favorable safety and tolerability profile in the Phase 1b study, successfully meeting its primary endpoint. 

The treatment was also assessed for effectiveness using several secondary and exploratory measures, including the Six-Minute Walk Test (6MWT), Quantitative Myasthenia Gravis (QMG) score, and Myasthenia Gravis Activities of Daily Living (MG-ADL) score. Over the course of the 12-week study, patients with DOK7-CMS who received ARGX-119 showed consistent improvements across these efficacy measures.

Luc Truyen, M.D., Ph.D., Chief Medical Officer of argenx, said in a statement, “The results of our Phase 1b ARGX-119 study in congenital myasthenic syndromes, an ultra-rare disorder that affects patients from birth, builds on our experience and understanding of  myasthenic disorders and aligns with our aspiration to serve even more patients living with these debilitating  diseases.”

Peter Ulrichts, Ph.D., Chief Scientific Officer of argenx, stated, “ARGX-119 is the sixth molecule developed through our Immunology Innovation Program to show proof-of-concept, reflecting the strength of our innovation model where our deep knowledge of the biology and expertise in antibody engineering come together to push the boundaries of what’s possible. argenx remains focused on uncovering new biological insights into misunderstood diseases to meaningfully change the lives of patients who have long-been underserved.”

Detailed findings from the trial will be shared at an upcoming medical conference. The company’s decision to advance ARGX-119 into a registrational study marks a key step in its efforts to develop new treatment options for individuals living with rare neuromuscular conditions like CMS.