SecProbe.io

October 17, 2013

Via E-mail
Ms. Rachel King
Chief Executive Officer
GlycoMimetics, Inc.
401 Professional Drive, Suite 250
Gaithersburg, MD 20879

Re: GlycoMimetics, Inc.
Registration Statement on Form S -1
Filed October 4, 2013
  File No. 333-191567

Dear Ms. King :

We have reviewed your registration statement  and have the following comment .

Please respond to this letter by amending your registration statement and providing the
requested information .  If you do not believe our comment applies  to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to this comment , we may have  additional comments.

Note 8: Research and License Agreements, page F -19

1. Please refer to your response to comment 27 and address the following additional
comments:

 Please tell us how e ach potential future development and regulatory milestones are
substantive if you have no further responsibilities for the development of the program
after completion of the Phase 2 clinical trial in April 2013 consistent with your
response to comment 26.   Please refer to ASC 605 -28-25-2a.
 Please revise your disclosure regarding aggregated milestones to disclose the nature
of the various milestone triggering events for each aggregated category of milestones
you disclosure.   Specifically for your regulatory milestones, please clarify whether
these milestones include those only for regulatory approval or whether they also
include milestones for the submission of regulatory filings.
 Notwithstanding your assertion of “information overload,” please revise your
disclosure to separately disclose the triggering event and related contingent
consideration for any individually significant milestone.   If you do not believe that

Ms. Rachel King
GlycoMimetics, Inc.
October 17, 2013
Page 2

 any individual milestone is significant, please demonstrate to us why not by providing
us a br eak-down of all of your individual milestones and an explanation why each is
not significant.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 193 3 and
all applicable Securities  Act rules require.   Since the company and its management are in
possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have  made.

Notwithstanding our comments, in the event you request acceleration of the effective date
of the pending regist ration statement please provide  a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pu rsuant to delegated authority, declare the
filing effective, it does not foreclose the Commission from taking any action with respect
to the filing;

 the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its full responsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company  may not assert staff comments and the declaration of effectiveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding requests for  acceleration .  We will consider a
written request for acceleration of the effective date of the registration statement as confirmation
of the fact that those requesting acceleration are aware of their respective responsibilities under
the Securities Act of  1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Please allow
adequate time  for us to review any amendment prior to the requested effective date o f the
registration statement.

Ms. Rachel King
GlycoMimetics, Inc.
October 17, 2013
Page 3

 You may contact Scott Wuenschell  at (202) 551 -3467  or Mark Brunhofer at (202) 551 -
3638  if you have questions regarding comments on the financial statements and related matters.
Please contact Matthew Jones  at (202) 551 -3786, Dan Greenspan at (202) 551 -3623, or me at
(202) 551 -3715  with any other questions.

Sincerely,

 /s/ Daniel Greenspan for

Jeffrey P. Riedler
Assistant Director

cc:  Brent Siler
Cooley LLP
11951 Freedom Drive
Reston, VA 20190