argenx announces presentation of updated ARGX-110 phase 1 data in TCL at EHA 2016

Breda, the Netherlands / Ghent, Belgium – argenx (Euronext Brussels: ARGX), a clinical-stage biopharmaceutical company focused on creating and developing differentiated therapeutic antibodies for the treatment of cancer and severe autoimmune diseases, today announced the presentation of efficacy and safety data from its Phase 1 expansion study of ARGX-110 in patients with T-cell lymphoma (TCL) during an e-poster session at the European Hematology Association (EHA) Annual Congress (Copenhagen, Denmark).

The data from the Phase 1 expansion study show evidence of clinical and/or biological anti-tumor activity with ARGX-110 in highly refractory cutaneous TCL & peripheral TCL patients with confirmed overexpression of CD70. The abstract can be accessed here.

The data presented today during EHA 2016 are very encouraging and further support the important role of CD70 in the TCL patient population. We are seeing signs of biological activity in both CTCL and PTCL patients that have failed standard therapy, as well as favourable safety profiles, so we are eager to present the full data set later this year in this critical indication, said Tim van Hauwermeiren, Chief Executive Officer of argenx. We remain on track with patient recruitment, which we expect to complete by mid 2016.

About ARGX-110

ARGX-110 is a SIMPLE Antibody™ targeting CD70, an immune checkpoint target involved in hematological malignancies, several solid tumors and severe autoimmune diseases. ARGX-110 works in three ways: i) blocks growth of tumor cells, ii) kills cancer cells and iii) restores immune surveillance against tumors(Silence K. et al. mAbs 2014; 6 (2):523-532). ARGX-110 is currently being evaluated in both hematological and solid tumors.

About argenx

argenx combines the diversity of the llama immune system with antibody engineering to advance a clinical pipeline to treat patients with cancer and autoimmune diseases. Our platforms allow us to unlock novel and complex targets and develop antibody-based drugs designed for greater efficacy and longer duration of effect. The strength of our team, our deep understanding of the biology and our committed collaborations with industry leaders contribute to the success of our journey.

argenx is listed on the Euronext Brussels exchange under the symbol ARGX.

SIMPLE Antibody™, NHance™ and ABDEG™ are trademarks of argenx NV

POTELLIGENT® is a trademark of BioWa Inc.

For further information, please contact:

Joke Comijn, Communications & Investor Relations Manager

+32 (0)477 77 29 44

+32 (0)9 310 34 19

[email protected]

Beth DelGiacco (US IR)

Stern Investor Relations

+1 212 362 1200

[email protected]

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