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Highlights:

  • ARGX receives EC approval for VYVGART SC to treat adult CIDP after prior therapies.
  • The company’s ADHERE study showed 61% relapse risk reduction versus placebo.
  • ARGX’s subcutaneous injection now approved in all EU member states and three EEA countries. 

argenx SE (Euronext & Nasdaq: ARGX) is a biopharmaceutical company focused on the development of antibody-based treatments for severe autoimmune diseases. Through collaborations with academic researchers, argenx aims to build a portfolio of immune-mediated therapies. The company is advancing its FcRn blocker, efgartigimod, across multiple indications and stages of clinical development. 

The company has received approval from the European Commission (EC) for its subcutaneous formulation of VYVGART (efgartigimod alfa) 1000 mg. The treatment is authorised as a monotherapy for adults with progressive or relapsing active chronic inflammatory demyelinating polyneuropathy (CIDP), following previous treatment with corticosteroids or immunoglobulins. The approval allows administration via vial or prefilled syringe and may be performed by the patient, caregiver, or healthcare professional. 

The dosing begins with a weekly regimen, which may be adjusted to every other week based on a physician’s assessment. 

CIDP is a rare autoimmune disorder of the peripheral nervous system that causes pain, weakness, and impaired mobility. The condition often progresses over time and can lead to severe disability. According to patient organisations, the EC approval represents a meaningful development for the CIDP community, which has had limited treatment options for decades. 

The decision by the EC follows a positive recommendation from the Committee for Medicinal Products for Human Use (CHMP) and is supported by data from the ADHERE trial, — the largest global study in CIDP to date. In the double-blind, placebo-controlled trial, 66.5% (214 out of 322) of patients receiving VYVGART SC showed clinical improvement in function, strength, and mobility. 

The trial met its primary endpoint with a statistically significant reduction in relapse risk compared to placebo (hazard ratio: 0.39, p<0.0001). Clinical benefits were observed across various patient subtypes, regardless of their prior treatment history. Additionally, 99% of participants in the trial opted to continue into the open-label extension phase. 

Safety results from ADHERE were consistent with prior studies of efgartigimod SC. The approval applies across all 27 EU member states, as well as Iceland, Liechtenstein, and Norway. argenx stated that it is coordinating with regulatory agencies in these regions to facilitate access. 

The EC’s authorization of VYVGART SC for CIDP follows an earlier approval for the same product in the treatment of generalized myasthenia gravis (gMG) in antibody-positive adults. VYVGART SC becomes the first new therapy with a novel mechanism of action for CIDP approved in more than three decades. 

ADHERE was conducted in two parts: an open-label Stage A and a randomised, placebo-controlled Stage B. Participants in Stage A were confirmed to have active CIDP and showed disease progression after withdrawal of ongoing therapies. Clinical improvement was required to enter Stage B, where patients were randomized to receive either VYVGART SC or placebo for up to 48 weeks. The primary measure was time to relapse, defined as deterioration on the adjusted INCAT scale. 

Beyond CIDP, efgartigimod SC is currently being investigated in over 15 autoimmune diseases linked to IgG antibodies. The compound is a fragment of a human IgG1 antibody that targets the neonatal Fc receptor (FcRn), disrupting the recycling of pathogenic IgG. This mechanism reduces levels of circulating autoantibodies involved in autoimmune conditions. 

Efgartigimod SC is marketed under various names globally: VYVGART Hytrulo in the United States and China, VYVDURA in Japan, and VYVGART in the EU and other countries. In Europe, the latest approval expands its therapeutic reach to CIDP, joining the previously approved indication for gMG.