[HEMISPHERX LETTERHEAD]



                                                              September 22, 2006



Amy C. Bruckner
Staff Accountant
Division of Corporation Finance
Securities and Exchange Commission
100 F Street, NE
Washington, DC 20549

         Re:      Hemispherx Biopharma, Inc.
                  Item 4.01 Form 8-K Filed September 20, 2006
                  File No. 001-13441


Dear Ms. Bruckner:

Hemispherx  Biopharma,  Inc.  (the  "Company")  hereby  responds to the comments
contained in your September 20, 2006 comment letter. Response numbers correspond
to the comment numbers in your letter.

Item 4.01 Form 8-K Filed September 20, 2006


Comment No. 1 Please revise your filing to specify the exact resignation date of
BDO Seidman,  LLP.  Please also state  explicitly  whether  during your two most
recent  fiscal  years ended  December  31, 2005 and  subsequent  interim  period
through the date of resignation there were any  disagreements  with BDO Seidman,
as described in Item  304(a)(1)(iv)  of Regulation  S-K. You should  specify the
"interim period" as the "interim period through  September 18, 2006," if that is
the actual resignation date.

Response. As disclosed in the Form 8-K, BDO Seidman has not resigned yet and has
informed the Company that it  anticipates  that it will resign no later than the
date of the Company's  filing of its third quarter Form 10-Q. As discussed  with
the Staff,  the Company  has filed an  amendment  to its Form 8-K (the  "8-K/A")
disclosing  that it will  amend the Form 8-K to  disclose  the  resignation  and
update the other information contained therein after BDO actually resigns.

Comment No. 2 Please  amend your  filing to  include,  as Exhibit 16, the letter
from your former accountants, BDO Seidman, LLP, as required by Item 304(a)(3) of
Regulation  S-K. If you do not intend to file an amendment to include Exhibit 16
within ten business days, please tell us why.

Response.  The requisite letter is filed with the 8-K/A. The Company understands
that it will have to obtain and file an updated  letter from BDO Seidman when it
files an  additional  Form 8-K  amendment at the time that BDO Seidman  actually
resigns.

The Company  acknowledges  that:  (i) it is  responsible  for the  adequacy  and
accuracy  of the  disclosure  in the filing;  (ii) staff  comments or changes to
disclosure in response to staff  comments do not foreclose the  Commission  from
taking any action  with  respect to the  filing;  and (iii) the  Company may not
assert staff comments as a defense in any proceeding initiated by the Commission
or any person under the federal securities laws of the United States.


                                                       Very truly yours,

                                                       /s/ Robert Peterson
                                                       -----------------------
                                                       Robert Peterson,
                                                       Chief Financial Officer