Hemispherx Biopharma Announces $16 Million Public Equity Offering

PHILADELPHIA, May 19, 2009 (GLOBE NEWSWIRE) -- Hemispherx Biopharma (NYSE
Amex:HEB) announced today that it has agreed to sell up to $16 million in common
stock and warrants in a registered offering to two institutional investors. The
investors will purchase for $16 million cash, 11,906,976 common shares of its
stock at $1.34375 per share.

Investors will also receive warrants to purchase 4,167,442 shares of Hemispherx
Biopharma, Inc.'s common stock. The warrants have an exercise price of $1.31 per
share and are exercisable at any time after the closing of the transaction and
before the fifth anniversary of such initial issuance date.

The closing of the offering is expected to take place subject to the
satisfaction of customary closing conditions, including the approval of an
application for the listing of additional shares by the NYSE Amex exchange.
Hemispherx Biopharma, Inc. plans to use the net proceeds from the offering to
fund commercialization of Alferon N and for other research and development and
general corporate purposes.

Rodman & Renshaw, LLC, a subsidiary of Rodman & Renshaw Capital Group, Inc.
(Nasdaq:RODM), acted as the exclusive placement agent for this transaction.

A shelf registration statement relating to the Common Stock and warrants to be
issued in the offering, and to the common stock underlying the warrants, has
been filed with the Securities and Exchange Commission. Copies of the prospectus
supplement and accompanying base prospectus may be obtained directly from
Hemispherx Biopharma, 1617 JFK Boulevard, Philadelphia, PA 19103. This
announcement is neither an offer to sell nor a solicitation of an offer to buy
any of our common stock or associated warrants. No offer, solicitation or sale
will be made in any jurisdiction in which such offer, solicitation or sale is
unlawful.

About Hemispherx Biopharma

Hemispherx Biopharma, Inc. is a specialty pharma company engaged in the
manufacture and clinical development of new drug entities for treatment of
seriously debilitating disorders. Hemispherx's flagship products include Alferon
N Injection(r) (FDA approved for a category of sexually transmitted diseases)
and the experimental therapeutics, Ampligen(r) and Oragens. Ampligen(r) and
Oragens represent experimental RNA nucleic acids being developed for globally
important debilitating diseases and disorders of the immune system. Hemispherx's
platform technology includes large and small agent components for potential
treatment of various severely debilitating and life threatening diseases.
Hemispherx has in excess of 50 issued patents comprising its core intellectual
property estate and a fully commercialized product (Alferon N Injection(r)). The
Company wholly owns and exclusively operates a GMP certified manufacturing
facility in the United States for commercial products. For more information
please visit www.hemispherx.net.

Information contained in this news release other than historical information,
should be considered forward-looking and is subject to various risk factors and
uncertainties. For instance, the strategies and operations of Hemispherx involve
risk of competition, changing market conditions, change in laws and regulations
affecting these industries and numerous other factors discussed in this release
and in the Company's filings with the Securities and Exchange Commission. Any
specifically referenced investigational drugs and associated technologies of the
Company (including Ampligen(r), Alferon LDO and Oragens) are experimental in
nature and as such are not designated safe and effective by a regulatory
authority for general use and are legally available only through clinical trials
with the referenced disorders. The forward-looking statements represent the
Company's judgment as of the date of this release. The Company disclaims,
however, any intent or obligation to update these forward-looking statements.
Clinical trials for other potential indications of the approved biologic Alferon
N Injection(r) do not imply that the product will ever be specifically approved
commercially for these other treatment indications; similarly, the completion of
the NDA filing process with Ampligen(r) does not imply that the product will
ever be approved commercially.

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CONTACT: Hemispherx Biopharma, Inc.
Dianne Will
518-398-6222
ir@hemispherx.net

CCG Investor Relations
Investor Contact:
Mark Collinson
310-477-9800