argenx to host conference call & webcast to report second quarter business update

Breda, the Netherlands / Ghent, Belgium – 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 it will host a conference call and audio webcast on Thursday, August 2, 2018 at 3:00 p.m. CEST (9:00 a.m. EDT) to discuss financial results for the first half of 2018 and to provide a second quarter business update.

To participate in the conference call, please select your phone number below, and use the confirmation code 7669735. The webcast may be accessed on the homepage of the argenx website at www.argenx.com or by clicking here.

Dial-in numbers:

Please dial in 5–10 minutes prior to 3 p.m. CET/ 9 a.m. EDT using the number and conference ID below.

Confirmation Code: 7669735

United Kingdom:+44 330 336 9411

National free phone – United Kingdom: 0800 279 7204

USA:+1 929 477 0448

National free phone – USA:888 599 8686

France: +33 1 76 77 22 57

National free phone - France:0805 101 278

Belgium:+32 2 400 6926

National free phone - Belgium: 0800 38625

Netherlands: +31 20 703 8261

National free phone - Netherlands: 0800 265 9169

A question and answer session will follow the presentation of the results. Go to www.argenx.com to access the live audio webcast. The archived webcast will also be available (90 days) for replay shortly after the close of the call from the Downloads section of the argenx website.

About argenx

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. The company is 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. argenx’s ability to execute on this focus is enabled by its suite of differentiated technologies. The SIMPLE AntibodyTM Platform, based on the powerful llama immune system, allows argenx to exploit novel and complex targets, and the three antibody engineering technologies are designed to enable expansion of the therapeutic index of the company’s product candidates.

www.argenx.com

For further information, please contact:

Joke Comijn, Director Corporate Communications & Investor Relations (EU)

+32 (0)477 77 29 44

+32 (0)9 310 34 19

info@argenx.com

Beth DelGiacco, VP Investor Relations (US)

+1 518 424 4980

bdelgiacco@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 can be identified by the use of forward-looking terminology, including the terms believes, estimates, anticipates, expects, intends, may, will, or should, and include statements argenx makes concerning the intended results of its strategy and argenx’s advancement of, and anticipated clinical development and regulatory milestones and plans. 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 argenx’s expectations regarding its the inherent uncertainties associated with competitive developments, preclinical and clinical trial and product development activities and regulatory approval requirements; argenx’s reliance on collaborations with third parties; estimating the commercial potential of argenx’s product candidates; argenx’s ability to obtain and maintain protection of intellectual property for its technologies and drugs; argenx’s limited operating history; and argenx’s ability to obtain additional funding for operations and to complete the development and commercialization of its product candidates. A further list and description of these risks, uncertainties and other risks 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 uncertainties, the reader is advised not to place any undue reliance on such forward-looking statements. These forward-looking statements speak only as of the date of publication of this document. 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.