argenx to Present Phase 3 ALKIVIA Results in Autoimmune Myositis as a Late-Breaking Oral Presentation at ACR Convergence 2026
Efgartigimod was well-tolerated, with an observed safety profile consistent with prior studies and its known safety profile.
Sentiment and the balance of points
Rhea-AI Sentiment reads the wording of the document, how positive or negative its language is on a 1 to 5 scale. The balance of points shown with the takes weighs what the document actually discloses, so the two can disagree, for example when a trial that missed its main goal is described in upbeat language.
Rhea-AI Summary
argenx (ARGX) announced that its Phase 3 ALKIVIA trial of efgartigimod in autoimmune myositis met its primary endpoint versus placebo. At Week 52, the combined population with immune-mediated necrotizing myopathy (IMNM) and dermatomyositis (DM) achieved a mean Total Improvement Score (TIS), a measure of disease improvement, of 47.95 versus 32.56. The improvement was 15.4 points greater with efgartigimod (p=0.0011).
Disease activity improvements appeared as early as Week 4 and persisted through 52 weeks, even with steroid tapering. In both subtypes, a greater proportion of patients receiving efgartigimod reached TIS ≥ 40, and the median time to that threshold was shorter than with placebo. The results will be presented in a late-breaking oral session at ACR Convergence 2026 in Orlando on November 11, from 9:15–9:30 a.m. ET.
How this balance works
Rhea-AI gives every point it takes from this document a weight. Minor counts 1, Moderate 3 and Major 9, so one Major point outweighs several Minor ones. The bar adds up the weights on each side, and when neither side holds more than 65% of the total the balance reads Mixed.
It reads the document as published, with the same rules for every company, and it does not look at what the market expected or at how the stock traded, so a point can be objectively good on a day the stock falls.
Rhea-AI Sentiment measures something else, the tone of the wording.
Positive
- Major pointPrimary endpoint met: Week 52 mean TIS improved 15.4 points more than placebo in combined IMNM/DM patients (p=0.0011).
- Minor pointDisease activity improvements appeared as early as Week 4 and persisted through 52 weeks, even with steroid tapering.
- Minor pointTIS ≥ 40 was achieved by a greater proportion of efgartigimod-treated patients versus placebo in both subtypes.
- Minor pointMedian time to TIS ≥ 40 was shorter with efgartigimod versus placebo in both subtypes.
- Minor pointEfgartigimod was well-tolerated, with observed safety consistent with prior studies and its known safety profile.
Negative
- None.
Key Figures
- Greater mean TIS improvement
- 15.4 points
- Efgartigimod versus placebo at Week 52 in the combined IMNM and DM population
- Mean TIS
- 47.95 vs. 32.56
- Efgartigimod vs. placebo at Week 52 in the combined IMNM and DM population
- P-value
- p=0.0011
- Primary endpoint in the combined IMNM and DM population
- Improvement duration
- Week 4 through 52 weeks
- Disease-activity improvements in the combined IMNM and DM population
Key Terms
fcrn medical
immune-mediated necrotizing myopathy medical
dermatomyositis medical
AI-generated analysis. How Rhea-AI works. Not financial advice.
- Results from the global Phase 3 ALKIVIA study, the first registrational study investigating an FcRn blocker in autoimmune myositis, show efgartigimod provides clinically meaningful improvements in IMNM and DM
- Patient improvements observed as early as Week 4 and sustained through 52 weeks
- Late-breaking oral presentation on Wednesday, November 11th, 9:15 – 9:30 AM ET
October 19, 2026, 8:00 AM ET
Amsterdam, the Netherlands – argenx SE (Euronext & Nasdaq: ARGX), the immunology innovation company, today announced that new data from the Phase 3 study evaluating VYVGART® Hytrulo (efgartigimod alfa and hyaluronidase-qvfc) in patients with autoimmune myositis, focused on immune-mediated necrotizing myopathy (IMNM) and dermatomyositis (DM), will be featured as a late-breaking oral presentation (#LB24) during the American College of Rheumatology (ACR) Convergence 2026 from November 6-11, 2026, in Orlando, Florida.
“ALKIVIA provides the first Phase 3 evidence that precisely targeting FcRn with efgartigimod can deliver clinically meaningful benefit for patients living with autoimmune myositis, for which very few treatment options exist, and in the case of IMNM, patients have no approved treatment options at all,” said Luc Truyen, M.D., Ph.D., Chief Medical Officer, argenx. “At ACR, we look forward to sharing ALKIVIA results that deepen the rheumatology community’s understanding of how IgG autoantibodies drive IMNM and DM and advance our ambition to transform the treatment paradigm.”
In the ALKIVIA study, efgartigimod showed rapid, sustained, and clinically meaningful improvements
- The Phase 3 ALKIVIA study met its primary endpoint, achieving a 15.4-point greater improvement in mean Total Improvement Score (TIS) versus placebo at Week 52 in the combined IMNM and DM population (47.95 vs. 32.56; p=0.0011).
- Improvements in disease activity for the combined IMNM and DM population were observed as early as Week 4 and were sustained through the full 52 weeks of treatment, even with steroid tapering.
- A greater proportion of IMNM as well as DM patients achieved a mean total improvement score of 40 or more (TIS ≥ 40) when treated with efgartigimod versus placebo. The median time to reach TIS ≥ 40 was also shorter with efgartigimod for both subtypes and was sustained through the full 52 weeks of treatment.
- Efgartigimod was well-tolerated in the study. The observed safety profile of efgartigimod was consistent with prior studies and the known safety profile of efgartigimod.
Details for the oral presentation are as follows:
- Efgartigimod PH20 SC in Adults With Idiopathic Inflammatory Myopathy: Results From the Phase 3, Randomized, Placebo-Controlled ALKIVIA Trial, LB24
Lead Author: Dr. Rohit Aggarwal
Date: Wednesday, November 11, 9:15 – 9:30 a.m. ET
More information on the data presented at the ACR Convergence 2026 Annual Meeting can be found here.
About the ALKIVIA study
The ALKIVIA trial was a global, randomized, double-blind, placebo-controlled, multicenter, operationally seamless Phase 2/3 study of efgartigimod SC for the treatment of autoimmune myositis across IMNM, DM and PM. The ALKIVIA study randomized 265 patients who had active disease and were on background treatment. Participants were randomized (1:1) to receive weekly injections of efgartigimod PH20 SC or matched placebo PH20 SC. The study was conducted in two phases, with an analysis of the Phase 2 portion of the clinical trial after the first 89 patients completed the study, followed by 176 patients in Phase 3. In the Phase 3 study, 175 patients received treatment. The Phase 3 study included a protocol-mandated corticosteroid taper throughout the study. The primary endpoint of Phase 3 was the mean Total Improvement Score (TIS) at the end of the treatment period of 52 weeks of all treated patients compared to placebo. Prespecified analyses evaluated the combined IMNM and DM population and each subtype separately. Scored from 0-100, TIS is an ACR/EULAR-validated composite endpoint based on six core set measures, including assessment of muscle strength and function; higher TIS values reflect greater overall clinical improvement. A TIS ≥ 40 is regarded by the clinical community as the point at which noticeable improvements in muscle strength, injury and functionality are observed.
ALKIVIA was conducted globally across North America, Europe, and Asia-Pacific, including China and Japan. argenx has an exclusive license agreement with Zai Lab for the development and commercialization of VYVGART and VYVGART Hytrulo in Greater China. Through this agreement, Zai Lab recruited Chinese patients into the ALKIVIA trial.
About Autoimmune Myositis
Autoimmune myositis is a heterogenous disease spectrum with autoimmune-mediated pathophysiology, characterized by chronic inflammation and progressive muscle weakness, and in some subtypes by skin involvement and other extramuscular manifestations. Proximal muscle weakness is a hallmark clinical feature across subtypes.
Approximately 100,000 people in the United States live with autoimmune myositis, including approximately 20,000 with immune-mediated necrotizing myopathy (IMNM) and approximately 40,000 with dermatomyositis (DM). Up to
Advances in the understanding of autoimmune myositis biology have highlighted the central role of antibody-mediated immunity, with pathogenic IgG autoantibodies contributing to muscle fiber damage and extramuscular manifestations across subtypes.
About Efgartigimod and Efgartigimod SC
Efgartigimod (efgartigimod alfa fcab) is a human IgG1 antibody fragment that binds to the neonatal Fc receptor (FcRn), resulting in the reduction of circulating IgG autoantibodies. It is the first approved FcRn blocker for the treatment of generalized myasthenia gravis (gMG) and chronic inflammatory demyelinating polyneuropathy (CIDP) globally, and for primary immune thrombocytopenia (ITP) in Japan. Efgartigimod SC is a subcutaneous combination of efgartigimod alfa and recombinant human hyaluronidase PH20 (rHuPH20), Halozyme’s ENHANZE® drug delivery technology to facilitate subcutaneous injection delivery of biologics.
About argenx
argenx is the immunology innovation company, focused on turning immunology breakthroughs into medicines for patients. The company seeks novel biology wherever it emerges, co-creating with academic researchers through its Immunology Innovation Program (IIP) and investing in promising science, to develop treatments for people living with underserved diseases. By advancing molecules with the potential to reach multiple diseases and patient populations, argenx is building a world-class portfolio. This approach produced the first approved antibody fragment targeting the neonatal Fc receptor (FcRn) and today powers a growing pipeline of early and late-stage programs across several therapeutic areas. For more information, visit www.argenx.com and follow us on LinkedIn, Instagram, Facebook, and YouTube.
Media:
Kate Dion
kdion@argenx.com
Colin McBean
cmcbean@argenx.com
Investors:
Alexandra Roy
aroy@argenx.com
FORWARD LOOKING STATEMENTS
The contents of this announcement include statements that are, or may be deemed to be, “forward-looking statements.” These forward-looking statements generally can be identified by the use of forward-looking words, such as “aim”, “anticipate”, “aspire”, “believe”, “can”, “continue”, “could”, “estimate”, “expect”, “entail”, “forecast”, “future”, “goals”, “hope”, “intend”, “is designed to”, “likely”, “may”, “might”, “objective”, “plan”, “possible”, “potential”, “pursue”, “project”, “predict”, “seek”, “should”, “strategy”, “target”, “will” and other words and terms of similar meaning and expression, including in connection with any discussion of future operating or financial performance. By their nature, forward-looking statements involve risks and uncertainties and readers are cautioned that any such forward-looking statements are not guarantees of future performance. argenx’s actual results may differ materially from those predicted by the forward-looking statements as a result of various important factors, including but not limited to, the results of argenx’s clinical trials; uncertainties associated with the development of novel drug therapies; preclinical and clinical trial and product development risks and setbacks; interpretation of argenx’s clinical trial data by regulatory authorities and argenx’s ability to obtain regulatory approval; the risk that early stage clinical trials may not be predictive of results in later stage or large scale clinical trials; the occurrence of adverse safety events or participant dropouts; the acceptance of its products and product candidates by its patients as safe, effective, and cost-effective; the impact of governmental laws and regulations, including tariffs, export controls, sanctions and other regulations on its business; the impact of healthcare regulations, including rules on reimbursement for argenx’s products; competition in drug discovery, development and commercialization efforts; its reliance on third-party suppliers, service providers and manufacturers; and instability and conflicts in the regions in which the company has suppliers or markets for its products. A further list and description of these and other risks, uncertainties, and factors that could cause actual results to differ materially from those referred to in the forward-looking statements can be found in argenx’s U.S. Securities and Exchange Commission (SEC) filings and reports, including in argenx’s most recent annual report on Form 20-F filed with the SEC as well as subsequent filings and reports filed by argenx with the SEC. Given these risks and uncertainties, the reader is advised not to place undue reliance on such forward-looking statements. These forward-looking statements speak only as of the date of publication of this press release. argenx undertakes no obligation to publicly update or revise the information in this press release, including any forward-looking statements, except as may be required by law.
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
What did argenx's Phase 3 ALKIVIA trial show in autoimmune myositis?
ALKIVIA met its primary endpoint, with efgartigimod producing a 15.4-point greater improvement in mean Total Improvement Score versus placebo at Week 52. Scores were 47.95 versus 32.56 in the combined IMNM and DM population (p=0.0011).
What safety findings did argenx report from the ALKIVIA trial?
Efgartigimod was well-tolerated in ALKIVIA. Its observed safety profile was consistent with prior studies and the known safety profile of efgartigimod.