SecProbe.io

May 22 , 2013

Via E -mail
Geert Cauwenbergh, Dr. Med. Sc.
President and Chief Executive Officer
RXi Pharmaceuticals Corporation
1500 West Park Drive, Suite 210
Westborough, MA 01581

Re: RXi Pharmaceuticals Corporation
  Registration Statement on Form S-1
Filed  May 10 , 2013
  File No.  333-188539

Dear Dr. Cauwenbergh :

We have limited our review of your registration statement to those issues we have
addressed in our 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 amending your registration statement and providing the
requested information .  Where 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 any amendment to your registration statement and the information you
provide in response to these  comments , we may have  additional comments.

General

1. We are currently processing your  request s for conf idential treatment .  Please be advised
that we will not be in a position to declare this registration statement effective until we
resolve all issues concerning the pending confidential treatment request s.

2. Please either update your financial statements to reflect the most recent quarterly
financial results or revise the prospectus to specifically  incorporate by reference the Form
10-Q filed on May 15, 2013.  Please refer to Gen eral Instruction VII and Item 12 of Form
S-1 and  Question 113.05 of the Securities Act Forms Compliance a nd Disclosure
Interpretations for more information on incorporation by reference.

Geert Cauwenbergh, Dr. Med. Sc.
RXi Pharmaceuticals Corporation
May 22 , 2013
Page 2

 Selling Stockholders, page 23

3. Please e xpand this section to specifically state, if true, that at the time of the purchase of
the se curities to be resold, no selling stockholder  had any agreements or understandings,
directly or indirectly, with any person to distribute the securities.

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 registration statement please provide a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pursuant to delegated authority, declare the
filing effective, it does not foreclose the Commissi on 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 acc uracy 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 thei r 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 rev iew any amendment prior to the requested effective date of the
registration statement.

Geert Cauwenbergh, Dr. Med. Sc.
RXi Pharmaceuticals Corporation
May 22 , 2013
Page 3

 Please contact Austin Stephenson at (202) 551 -3192 , Bryan Pitko at (202) 551 -3203 , or
me at (202) 551 -3715 with any  questions.

Sincerely,

 /s/ Bryan J. Pitko for

 Jeffrey P. Riedler
Assistant Director

cc: Via E -mail
Ryan A. Murr , Esq.
Ropes & Gray LLP