Exhibit 99.1

Company/Investor Contact:

Charles Jones

CJones & Associates Public Relations

888-557-6480

305-987-7418

cjones@cjonespr.com

Hemispherx Biopharma Announces 1-for-12 Reverse Stock Split

PHILADELPHIA – August 17, 2016 - Hemispherx Biopharma (NYSE MKT: HEB) (the “Company), announced today that it will effect a 1-for-12 reverse stock split of its common stock.

At the annual meeting of the Company's stockholders held earlier today, the stockholders approved an amendment to the Company's Certificate of Incorporation to effect the reverse stock split at a ratio in the range of 1-for-8 to 1-for-12. After the meeting, the Board of Directors approved the implementation of the reverse stock split at a ratio 1-for-12. The Company anticipates that the reverse stock split will be effective on August 26, 2016, and the Company's common stock will begin trading on a split-adjusted basis on August 29, 2016.

The reverse stock split will reduce the number of shares of the Company's common stock currently outstanding from approximately 248,932,220 shares to approximately 20,744,352 shares. All resulting fractional shares will be rounded up to the next whole share. Proportionate adjustments will be made to (i) the per share exercise price and the number of shares of common stock that may be purchased upon exercise of outstanding stock options granted by the Company and warrants issued by the Company and (ii) the number of shares of common stock issuable under the Company's 2009 Equity Incentive Plan. The number of authorized shares of the Company's common stock will remain unchanged.

The reverse stock split is intended to increase the per share trading price of the Company’s common stock to permit the Company to regain compliance with the continued listing requirements for the NYSE MKT. The Company's common stock will continue to trade on NYSE MKT under the symbol "HEB". A new CUSIP number of 42366C 301 has been assigned to the common stock in connection with the reverse stock split.

Information for Stockholders

Upon the effectiveness of the reverse stock split, each twelve (12) shares of the Company's common stock issued and outstanding will be automatically combined and converted into one share of common stock, par value $0.001 per share. No fractional shares will be issued in connection with the reverse stock split. Any fractional share of common stock that would otherwise have resulted from the reverse stock split will be rounded up to the nearest whole share.

The Company's transfer agent, Continental Stock Transfer & Trust., will act as exchange agent for the reverse stock split, and will provide stockholders of record holding certificates representing pre-split shares of the Company's common stock as of the effective date with a letter of transmittal providing instructions for the exchange of stock certificates for post-split shares. Stockholders owning shares via a broker or other nominee will have their positions automatically adjusted to reflect the reverse stock split, subject to the broker's or nominee's particular procedures for processing the reverse stock split, and will not be required to take any action in connection with the reverse stock split. Continental Stock Transfer & Trust can be contacted at (212) 509-4000.

Additional information about the reverse stock split can be found in the Company's definitive proxy statement filed with the Securities and Exchange Commission on June 27, 2016, a copy of which is available at www.sec.gov and at www.hemispherx.net under the SEC Filings tab located on the Investor Relations page.

About Hemispherx Biopharma

Hemispherx Biopharma, Inc. is an advanced specialty pharmaceutical 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^® and the experimental therapeutics rintatolimod (tradenames Ampligen^® or Rintamod^®) and Alferon^® LDO. Rintatolimod is an experimental RNA nucleic acid being developed for globally important debilitating diseases and disorders of the immune system, including Chronic Fatigue Syndrome. Hemispherx’s platform technology includes components for potential treatment of various severely debilitating and life threatening diseases. Because both Rintatolimod and Alferon^® LDO are experimental in nature, they are not designated safe and effective by a regulatory authority for general use and are legally available only through clinical trials. Hemispherx has patents comprising its core intellectual property estate and a fully commercialized product (Alferon N Injection^®), approved for sale in the U.S. and Argentina. The FDA approval of Alferon N Injection® is limited to the treatment of refractory or recurrent external genital warts in patients 18 years of age or older. The Company’s Alferon N approval in Argentina includes the use of Alferon N Injection (under the pending brand name “Naturaferon”) for use in any patients who fail or become intolerant to recombinant interferon, including patients with chronic active hepatitis C infection. 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.

Forward-Looking Statements

To the extent that statements in this press release are not strictly historical, all such statements are forward-looking, and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as “intends,” “plans,” and similar expressions are intended to identify forward-looking statements. The inclusion of forward-looking statements should not be regarded as a representation by Hemispherx that any of its plans will be achieved. These forward-looking statements are neither promises nor guarantees of future performance, and are subject to a variety of risks and uncertainties, many of which are beyond Hemispherx’s control, which could cause actual results to differ materially from those contemplated in these forward-looking statements. Examples of such risks and uncertainties include those set forth in the Disclosure Notice, below, as well as the risks described in Hemispherx’s filings with the Securities and Exchange Commission, including the most recent reports on Forms 10-K, 10-Q and 8-K. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and Hemispherx undertakes no obligation to update or revise the information contained in this press release, whether as a result of new information, future events or circumstances or otherwise revise or update this release to reflect events or circumstances after the date hereof.

Disclosure Notice

The information in this press release includes certain "forward-looking” statements including without limitation statements about additional steps which the FDA may require and Hemispherx may take in continuing to seek commercial approval of the Ampligen^® NDA for the treatment of Chronic Fatigue Syndrome in the United States. The final results of these and other ongoing activities could vary materially from Hemispherx’s expectations and could adversely affect the chances for approval of the Ampligen^® NDA in the United States and other countries. The clinical studies referenced herein have been previously reviewed by the FDA and are not, in and of themselves, a sufficient basis for approval in the United States. Any failure to satisfy the FDA regulatory requirements or the requirements of other countries could significantly delay, or preclude outright, approval of the Ampligen^® NDA in the United States and other countries.

Information contained in this news release, other than historical information, should be considered forward-looking and is subject to various risk factors and uncertainties including, but not limited to, general industry conditions and competition; general economic factors; the Company’s ability to adequately fund its projects; the impact of pharmaceutical industry regulation and healthcare legislation in the United States and internationally; trends toward healthcare cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the Company’s ability to accurately predict the future market conditions; manufacturing difficulties or delays; dependence on the effectiveness of the Company’s patents and other protections for products; and the exposure to litigation, including patent litigation, and/or regulatory actions; and numerous other factors discussed in this release and in the Company’s filings with the Securities and Exchange Commission. The production of new Alferon® API inventory will not commence until the validation phase is complete. While the facility is approved by FDA under the Biological License Application ("BLA”) for Alferon®, this status will need to be reaffirmed by a successful Pre-Approval Inspection by the FDA prior to commercial sale of newly produced inventory product. The validation phase is delayed until we are able to repair the damage caused by a flood that occurred on January 5, 2016 at the facility. While we have made progress in repairing the damage at the facility, we cannot assure when all repairs required to be made prior to seeking Pre-Approval Inspection by the FDA. If and when we obtain a reaffirmation of FDA BLA status and have begun production of new Alferon® API, we will need FDA approval as to the quality and stability of the final product to allow commercial sales to resume. With regard to our NDA for Ampligen® to treat CFS, we note that there are additional steps which the FDA has advised us to take in our seeking approval. The final results of these efforts and/or any other activities could vary materially from Hemispherx’s expectations. Any failure to satisfy the FDA regulatory requirements or the requirements of other countries could significantly delay, or preclude outright, approval of Ampligen® in the United States and other countries. No evidence is suggested that Ampligen® will be commercially approved for any treatment or that Alferon N Injection® will be commercially approved for potential new treatment indications or for new manufacturing procedures. Approval of Ampligen^® for CFS in the Argentine Republic does not in any way suggest that the Ampligen^® NDA in the United States will obtain commercial approval. Also, it is noted that ANMAT approval is only an initial, but important, step in the overall successful commercialization. Namely, additional steps required for commercialization in Argentina will require, among others, an appropriate reimbursement level, appropriate marketing strategies, completion of manufacturing preparations for launch (including possible requirements for approval of final manufacturing, etc., and there are no assurances as to whether or when such multiple subsequent steps will be successfully performed to result in an overall successful commercialization and product launch. No assurance can be given as to whether the reverse stock split will alleviate the current NYSE MKT continued listing deficiency or what effect the reverse split will have on the trading price of our common stock.