Placement Agent Agreement

May 8, 2009

The purpose of this letter agreement (the “Agreement”) is to authorize Rodman & Renshaw, LLC (“Rodman”) to contact one or more institutional investors to explore the degree of interest, if any, of such investors in providing funding to Hemispherx Biopharma, Inc. or its affiliates (the “Company”). This authorization shall be exclusive to Rodman for a period of 30 days.  The Company may terminate Rodman’s authorization to contact investors hereunder at any time upon a 3-day written notice.  If the Company chooses to accept any funding, on terms to be mutually agreed upon by the Company and any such investor(s), then the Company shall pay to Rodman the fees set forth below if there is any funding of the Company (a “Financing”) within 6 months of the date of the termination or expiration of this Agreement by any investors with which Rodman arranged a conference call or a meeting for the Company during the term of this Agreement.

In consideration of the services rendered by Rodman under this Agreement, the Company agrees to pay Rodman a cash fee payable immediately upon the closing of any portion of the Financing equal to 5.5% of the aggregate proceeds raised or committed in such Financing from such investors, plus 5.5% warrant coverage.  In addition, but only if a Financing is consummated, the Company agrees to reimburse Rodman at closing for all reasonable travel and other out-of-pocket expenses incurred in connection with Rodman’s engagement, including the fees and expenses of Rodman’s counsel, not to exceed $25,000 without prior written approval by the Company.

The Company hereby makes to Rodman each of the representations and warranties made by the Company to the Purchasers in the Securities Purchase Agreement, to be entered into in connection with the Financing, as though restated in their entirety herein.

The Company hereby agrees to the indemnification and other agreements set forth in the Indemnification Provisions attached hereto as Addendum A , the provisions of which are incorporated herein by reference and shall survive the termination or expiration of this Agreement.

This Agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to conflicts of law principles.  Any dispute arising out of this Agreement shall be adjudicated in the courts of the State of New York or in the federal courts sitting in the Southern District of New York, and each of the parties hereto agrees that service of process upon it by registered or certified mail at its address set forth herein shall be deemed adequate and lawful.  Any rights to trial by jury with respect to any such dispute are hereby waived by Rodman and the Company. The Company shall indemnify Rodman against any liabilities arising under the Securities Act of 1933, as amended, attributable to any information supplied or omitted to be supplied to any investor by the Company pursuant to this Agreement.  The Company acknowledges and agrees that Rodman is not and shall not be construed as a fiduciary of the Company and shall have no duties or liabilities to shareholders or creditors of the Company or any other person by virtue of this Agreement or the retention of Rodman hereunder, all of which are hereby expressly waived.