Publication date: 24/04/2018
argenx (Euronext & Nasdaq: ARGX), a clinical-stage biotechnology company developing a deep pipeline of differentiated antibody-based therapies for the treatment of severe autoimmune diseases and cancer, today announced that it will present complete data from the Phase 2 proof-of-concept trial of efgartigimod (ARGX-113) in generalized myasthenia gravis (MG) patients at the 2018 American Academy of Neurology (AAN) Annual Meeting in Los Angeles, CA. These data will be presented during the Clinical Trial Plenary Session by James F. Howard Jr., M.D., principal investigator on the trial and Distinguished Professor of Neuromuscular Disease, Professor of Neurology, Medicine & Allied Health, and Chief, Neuromuscular Disorders Section, The University of North Carolina School of Medicine.
"We are very encouraged by the full set of data on efgartigimod that will be presented today at AAN, particularly the correlation of total and pathogenic IgG reduction and clinical response. The data show an early separation between treatment and placebo groups on efficacy scores that persisted for the total duration of the study. We believe this may be as a differentiator from current therapies for managing IgG levels, including plasmapheresis, where benefit reversed more rapidly," commented Nicolas Leupin, CMO of argenx. "We continue to learn more about the novel mechanism of action of our drug candidate and look forward to reporting data from two additional indications this year, immune thrombocytopenia and pemphigus vulgaris, which like MG, are diseases mediated by pathogenic IgGs."
The tolerability of efgartigimod remained consistent with findings from the Phase 1 trial in healthy volunteers. The study drug candidate was well-tolerated in all patients with no serious or severe adverse events reported, and most adverse events were characterized as mild and deemed unrelated to the drug candidate.
Key Highlights from Full Phase 2 Dataset
argenx is conducting two additional ongoing Phase 2 clinical trials of efgartigimod in immune thrombocytopenia (ITP) and pemphigus vulgaris (PV). Topline data from the ITP trial and interim data from the PV trial are both expected in the second half of 2018.
An investor workshop is being held today at 1:00 p.m. PT in Los Angeles to discuss the complete efgartigimod clinical data presented by Dr. Howard. A live webcast of the presentation will be available on the Company's website www.argenx.com or by clicking here. A replay of the webcast will be available for 90 days following the presentation.
Phase 2 Trial Design
The Phase 2 trial evaluated 24 MG patients with generalized muscle weakness, and a total MG-ADL score >=5, with more than 50% of the score consisting of non-ocular items. Patients were randomized to receive four weekly doses of either standard of care plus 10 mg/kg of ARGX-113, or standard of care plus placebo. Standard of care therapies included acetylcholinesterase inhibitors, corticosteroids and/or immunomodulatory agents. The primary endpoints of the trial were safety and tolerability. Secondary endpoints included efficacy as measured by the change from baseline of the MG-ADL, QMG, and MGC disease severity scores; impact on quality of life as measured by the MGQoL score; and an assessment of pharmacokinetics (PK) and pharmacodynamic (PD) markers and immunogenicity.
Efgartigimod (ARGX-113) is an investigational therapy for IgG-mediated autoimmune diseases and was designed to exploit the natural interaction between IgG antibodies and the recycling receptor FcRn. ARGX-113 is the Fc-portion of an antibody that has been modified by the argenx proprietary ABDEG(TM) technology to increase its affinity for FcRn beyond that of normal IgG antibodies. As a result, ARGX-113 blocks antibody recycling through FcRn binding and leads to fast depletion of the autoimmune disease-causing IgG autoantibodies. The development work on ARGX-113 is done in close collaboration with Prof. E. Sally Ward (University of Texas Southwestern Medical and Texas A&M University Health Science Center, a part of Texas A&M University (TAMHSC)).
argenx is a clinical-stage biotechnology company developing a deep pipeline of differentiated antibody-based therapies for the treatment of severe auto-immune diseases and cancer. We are focused on developing product candidates with the potential to be either first-in-class against novel targets or best-in-class against known, but complex, targets in order to treat diseases with a significant unmet medical need. Our ability to execute on this focus is enabled by our suite of differentiated technologies. Our SIMPLE AntibodyTM Platform, based on the powerful llama immune system, allows us to exploit novel and complex targets, and our three antibody engineering technologies are designed to enable us to expand the therapeutic index of our product candidates.