SecProbe.io

Mail Stop 4546
        March 28 , 2017

Tim Van Hauwermeiren
Chief Executive Officer
argenx N.V.
Willemstraat 5
4811 AH, Breda, the Netherlands

Re: argenx N.V.
Draft Registration Statement on Form F -1
Submitted March 1, 2017
  CIK No. 0001697862

Dear Mr. Van Hauwermeiren :

We have reviewed your draft registration statement  and have the following comments.  In
some of our comments, we may ask you to provide us with information so we may better
understand your disclosure.

Please respond to this letter by providing the requested information and either submitting
an amended draft registration statement or publicly filing your registration statement on
EDGAR.  If you do  not believe our comments apply to your facts and circumstances or do not
believe an amendment is appropriate, please tell us why in your response.

After reviewing the information you provide in response to these  comments  and your
amended draft registra tion statement or filed registration statement,  we may have  additional
comments.

Cover Page

1. We note your statement that the last reported sale price of your ordinary shares on
Euronext Brussels was €__, equivalent to $__ per share . You may  present  the most recent
home market trading price, converted to U.S. dollars at the most recent exchange rate ,
assuming the U.S. IPO price will be largely based on the home market trading price.
However, b ased on your disclosure on page 215, it appears that the IPO price will be
determined by negotiations between you and the representatives of the underwriters using
many factors and that the U.S. IPO price will not be substantially the same as the home
market trading price.  Please revise yo ur cover page to provide bona fide pricing
information.   See Item 501(b)(3) of Regulation S -K.

Tim Van Hauwermeiren
Argenx N.V.
March 28 , 2017
Page 2

 Summary
Overview, page 1

2. We note your disclosure that you commenced a Phase  1/2 clinical trial of ARGX -110 in
combination with azacitidine for the treatment of n ewly diagnose d AML or high -risk
MDS patients  in December 2016  and that you expect to initiate the Phase  2 part of a
Phase  1/2 clinical trial of ARGX -110 for the treatment of cutaneous TCL in March 2017.
Please disclose the requirements for a clinical tria l to be considered a Phase 1/2.

3. Please revise your product pipeline table here and in the Business section to remove
programs that are in the discovery phase.  Because you have not identified a product
candidate for these programs, it is premature to inc lude them in a product pipeline table.

4. Please include a column for Phase 3 in your product pipeline table.

5. We note your disclosure on page 5 that no significant trends in terms of safety were
observed between the dose groups for ARGX -110.  However, we no te that there were
seven patient deaths in the Phase 1 trials and there was one drug -related patient death
attributed to sepsis  in the Phase 1 safety -expansion .  Please balance your disclosure in
this section so that it does not imply that there are no par ticular safety risks related to
ARGX -110.

Implications of Being an Emerging Growth Company, page 8

6. Please supplementally provide us with copies of all written communications, as defined
in Rule 405 under the Securities Act, that you , or anyone authorized to do so on your
behalf , present to potential investors in reliance on Section 5(d) of the Securities Act,
whether or not they retain copies of the communications.

Risk Factors
We rely on third parties to supply and manufacture our p roduct candidates . . ., page 43

7. We note that you rely primarily on Lonza Sales AG for the manufacturing of the drug
substance of all your products.  We further note that you do not have alternative
production plans in place, and in case of a disruption y ou would have to establish
alternative plans which would require substantial capital and you would likely experience
months or years of manufacturing delays.  Please file your manufacturing agreement with
Lonza as an exhibit to the registration statement, or, in the alternative, please tell us why
you do not believe you are required to do so.

Intellectual property rights of third parties . . ., page 47

8. We note that you are aware of certain issued patents held by third parties that may cover
certain aspect s of your pro duct candidates  and if these patents have not expired at the

Tim Van Hauwermeiren
Argenx N.V.
March 28 , 2017
Page 3

 time of approval of your product candidates you may be subject to an infringement
action.  Please disclose the expiration date(s) for the patents at issue.

We have obtained signific ant funding from agencies of the government of the Flemish region . .
., page 57

9. Please revise to disclose what is considered a “fundamental change” to your shareholding
base that could cause Flemish agencies to re -evaluate subsidies granted to you.

Use of Proceeds, page 72

10. We note your disclosure regarding the intended use of funds to expand applications of
ARGX -113 to develop a subcutaneous formulation, including a Phase 1 clinical trial in
healthy volunteers and explore additional indications.  If the  anticipated proceeds will not
be sufficient to fund this use, please disclose the amount and sources of other funds
needed.  Refer to Item 3.C.1 of Form 20 -F.

Management ’s Discussion and Analysis of Financial Condition and Results of Operations
Critical Accounting Policies and Significant Judgments and Estimates
Measurement of Share -Based Payments, page 94

11. Please address the following regarding your disclosure that for grants beginning in 2016,
you only considered the historical volatility of your stock price calculated since your
initial public offering.
 Given the ten year option life and the fact that yo u have been a public company for
approximately two years, please tell us your consideration of B25(b) and B26 in IFRS 2.
 It appears that by limiting your consideration solely to your own share price volatility
data, the volatility assumption used in your  computations dropped to 40% on page F -10
for the options granted during 2016 from 59% as reported on page F -41 for the options
granted during 2015 using peer data.   To the extent you continue to believe that excluding
peer data which would cover a longer historical time period is appropriate, revise your
disclosure here to more clearly discuss the impact of that decision and provide
quantification to the extent possible.

Business , page 98

12. We note your disclosure on page 18 that you do not have any active INDs for your
proposed indications at this time nor have you conducted any of your clinical
development to date in the United States .  Please also disclose this in the Business
section .

Tim Van Hauwermeiren
Argenx N.V.
March 28 , 2017
Page 4

 Phase 1/2 Clinical Trial in Patients with Advanced Malignan cies Expressing CD70, page 118

13. Please disclose the definitions used for Grade 3 and Grade 4 drug -related adverse events.
Please also explain the types of serious adverse events that make up the 20 reported
serious adverse events, the number of patients w ho experienced these events and at which
does levels, and what is meant by “heavily pre -treated.”  Please also disclose the dose
levels for the seven patient deaths.

Collaborations, page 126
License Agreements, page 130

14. For each collaboration agreement  discussed, please present the amount of milestone
payments that the company may receive for each of development, regulatory and
commercial milestones.

15. Please present the royalty amount for the license agreement with Bird Rock Bio., Inc. in a
range t hat does not exceed ten percent  and disclos e the royalty term.

16. Please disclose the following for each of the license agreements, to the extent not already
disclosed:

 Nature and scope of intellectual property transferred;
 Duration of agreement and royalty term;  and
 Payment provisions, including total up front or execution payments received or paid,
aggregate amounts paid or received to date, the annual license maintenance fees,
aggregate future milestone payments , and profit or revenue sharing provisions.

Principal Shareholders, page 170

17. Please revise your disclosure to identify the natural person  or persons who hav e voting
and investment control  of the shares held by LSP IV Management B.V., Forbion Capital
Fund II Cooperatief U.A., Federated Equity Management  Company of Pennsylvania and
Perceptive Advisors LLC.

18. Please include the information required by  Item 7.A.2 of Form 20 -F.

Comparison of Dutch Corporate Law, our Articles of Association and Board By -Laws and U.S.
Corporate Law, page 185

19. We note your disclosure that the summary is subject to Dutch law, including Book 2 of
the Dutch Civil Code and Delaware corporation law, including the Delaware General
Corporation Law.  It is not appropriate to qualify your disclosure by reference to
infor mation that is not included in the prospectus or filed as an exhibit to the registration
statement.  Please revise accordingly.

Tim Van Hauwermeiren
Argenx N.V.
March 28 , 2017
Page 5

 General

20. Please provide us proofs of all graphics, visual, or photographic information you will
provide in the printed prospectus prior to its use, for example in a preliminary prospectus.
Please note that we may have comments regarding this material.

You may contact Sasha Parikh  at (202) 551 -3627 or Kevin Vaughn, Accounting Branch
Chief,  at (202) 551 -3494 if you have qu estions regarding comments on the financial statements
and related matters.  Please contact Ada D. Sarmento  at (202) 551 -3798 or Erin Jaskot, Special
Counsel,  at (202) 551 -3442 with any other questions.

Sincerely,

 /s/ Erin K. Jaskot, for

Suzanne Hayes
Assistant Director
Office of Healthcare and Insurance

cc:  Edwin O’Connor
 Goodwin Procter LLP