argenx SE

Report Publication Announcement • Aug 17, 2017

argenx to host conference call & webcast to report second quarter business update and half year 2017 financial results on August 24, 2017

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 24, 2017 at 3:00 p.m. CEST (9:00 a.m. EDT) to discuss financial results for the first half of 2017 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 3427020. The webcast may be accessed on the homepage of the argenx website at www.argenx.com or clicking here.

About argenx

argenx is a clinical-stage biotechnology company developing a deep pipeline of differentiated antibodybased therapies for the treatment of severe autoimmune diseases and cancer. We are focused on developing product candidates with the potential to be either first-in-class against novel targets or best-inclass 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 Antibody(TM) 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. www.argenx.com

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: 3427020

United Kingdom: +44 20 3427 1903 National free phone - United Kingdom: 0800 279 5004 USA: +1646 254 3367 National free phone - USA: 1877 280 2342 France: +33 1 76 77 22 22 National free phone - France: 0805 631 579 Belgium: +32 2 620 0138 National free phone - Belgium: 0800 58032 Netherlands: +31 20 716 8295 National free phone - Netherlands: 0800 020 2577

A question and answer session will follow the presentation of the results. The archived webcast will also be available for replay shortly after the close of the call from the "Downloads" section of the argenx website

For further information, please contact:

Joke Comijn, Corporate Communications Manager +32 (0)477 77 29 44 +32 (0)9 310 34 19 info@argenx.com

Beth DelGiacco (US IR) Stern Investor Relations +1 212 362 1200 beth@sternir.com

Forward-looking Statements

The contents of this announcement include statements that are, or may be deemed to be, "forwardlooking 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; its financial condition, results of operation and business outlook; the sufficiency of its cash, cash equivalents and current financial assets; and the momentum of its product candidate pipeline as well as the advancement of, and anticipated clinical development and regulatory milestones and plans related to, argenx's product candidates and preclinical and clinical trials. 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 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 the final prospectus related to argenx's initial U.S. public offering filed with the SEC pursuant to Rule 424(b) of the Securities Act of 1933, as amended, 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.