July 24, 2018

John Simard
President and Chief Executive Officer
XBiotech Inc.
8201 E. Riverside Drive, Bldg. 4, Suite 100
Austin, TX 78744

       Re: XBiotech Inc.
           Form 10-K for the Fiscal Year Ended December 31, 2017
           Filed March 16, 2018
           File No. 001-37347

Dear Mr. Simard:

       We have limited our review of your filing to the financial statements
and related
disclosures and have the following comment.

        Please respond to the comment within ten business days by amending the
filing or advise
us as soon as possible when you will respond. If you do not believe our comment
applies to your
facts and circumstances, please tell us why in your response.

       After reviewing your response to the comment, we may have additional
comments.

Form 10-K for the Fiscal Year Ended December 31, 2017

Exhibits

1.     Please amend your filing to provide the Exhibit 31 certifications
exactly as stipulated in
       Item 601(b)(31) of Regulation S-K. In this regard:
         Your introductory language in paragraph 4 does not refer to internal
control over
           financial reporting (ICFR); and
         You exclude paragraph 4(b) on ICFR in its entirety.
       This comment also applies to the certifications in your March 31, 2018
Form 10-Q.
 John Simard
XBiotech Inc.
July 24, 2018
Page 2

       In closing, we remind you that the company and its management are
responsible for the
accuracy and adequacy of their disclosures, notwithstanding any review,
comments, action or
absence of action by the staff.

       You may contact Keira Nakada at 202-551-3659 or Jim Rosenberg at
202-551-3679 with
any questions.

FirstName LastNameJohn Simard
Comapany NameXBiotech Inc.
                                                          Division of
Corporation Finance
July 24, 2018 Page 2                                      Office of Healthcare
& Insurance
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