Hemispherx: U.S. Army Scientists (USAMRIID) Find Ampligen(R) Produces 100% Survival Rate in Ebola Virus Rodent Study

Placebo Group Had a 100% Death Rate


PHILADELPHIA, Feb. 2, 2015 (GLOBE NEWSWIRE) -- Hemispherx Biopharma, Inc. (NYSE MKT:HEB) (the "Company" or "Hemispherx"), announced today the results of a new efficacy study of Ampligen® in a mouse model of Ebola virus (EBOV) infection performed by scientists at the U.S. Army Medical Research Institute of Infectious Disease (USAMRIID).

Ampligen® (rintatolimod), an experimental therapeutic, was utilized with a mouse adapted Ebola virus using multiple groups of mice with varying dosage schedules of Ampligen® given every other day. The most effective dose, resulting in 100% percent survival, corresponded to a human dose of approximately 400 mg, which has been used clinically approximately 50,000 times and has been generally well-tolerated when administered twice weekly. When higher doses of Ampligen® were used in the Ebola-infected mice, the survival rate dropped to 90%. The Ebola-infected mice treated with placebo had a 100% death rate by Day 7 post-infection.

Ebola virus disease appears to be a double-stranded RNA (dsRNA) deficiency disease in which the lethal sequelae stem from the inability of the host (mouse or human) to mount an effective innate immune response. As such, Ampligen®, an experimental therapeutic (and synthetic dsRNA), appears to directly address the underlying molecular deficiency in bio available dsRNA.

Ampligen® has a second property, potentially relevant to durable benefit in Ebola disease, in that it is believed to be insensitive to changes in viral structure and changes in molecular sequences. In a new publication in the journal mBio (Kugelman, et al. mBio 2015;6(1):e02227-14), scientists at the U.S. Army Medical Research Institute of Infectious Disease (USAMRIID), Harvard University, and Massachusetts Institute of Technology (MIT) studied genetic changes in the Ebola virus (EBOV) circulating in West Africa and concluded that genomic drift of the EBOV over time may be sufficient to block the action of otherwise potential therapies that target EBOV genetic sequences. The types of potential drugs at risk include monoclonal antibodies and small-interfering RNA (siRNA) which are scheduled to be evaluated during the current outbreak.

The two platform drugs of Hemispherx, Alferon® N and Ampligen®, both experimental therapeutics in a setting of Ebola disease, have recently both demonstrated anti-EBOV activity in culture (see Hemispherx' Press release dated November 3, 2014 http://www.hemispherx.net/content/investor/default.asp?goto=805) and have mechanisms of action which are multifaceted by working through cellular "molecular cascades" rather than by targeting viral protein or genetic sequences vulnerable to mutational change (Kugelman, et al. mBio 2015;6(1):e02227-14). Cellular antiviral pathways of innate immunity are not subject to the mutational pressures of rapidly dividing viruses, which suggests that - even in the face of viral mutation – biological modifier products activating innate immunity are likely to continue to show sustained biological activity.

Although none of the experimental drugs have been approved by the U.S. Food and Drug Administration (FDA), certain of the experimental therapeutics discussed in the USAMRIID/Harvard/MIT report, are being used to treat small numbers of patients under a World Health Organization (WHO) emergency protocol. The potential impact of genomic drift on development of therapeutics for EBOV disease has already been realized for other pathogenic human virus, such as HIV and influenza. The large genetic and antigenic diversity seen in HIV has been a "major stumbling block" for development of preventative vaccines (Ndung'u and Weiss. AIDS 2012;26(10):1255-60).

In a highly mutational rate setting, use of antiviral drugs that target genomic or protein sequences, may accelerate the onset of drug resistant viral strains, as has been reported previously with influenza and application of Tamiflu (Chao, et al. J R Soc Interface 2012;9(69):648-56), thus the proposed use of experimental drugs whose action is sequence specific is not without additional theoretical risks.

Additional potentially favorable properties of Ampligen® are its well-studied and documented adverse event profile, which provides over 600 patient years of patient safety data and a proven record at manufacturing at a scale to treat more than 1,000 human subjects with this experimental therapeutic.

About Alferon® N

Alferon® N is the only natural source, multi-species alpha interferon currently approved for sale in the U.S. Alferon® N is approved in the U.S. for the treatment of refractory or recurring external genital warts caused by human papilloma virus in patients 18 years of age, or older. Positive results against Ebola in vitro have been reported to the Company by the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID). Clinical trial data will be necessary to establish human efficacy of Alferon® N for Ebola virus.

About Ampligen®

Ampligen®, an experimental therapeutic, is a new class of specifically-configured ribonucleic acid (RNA) compounds targeted as potential treatment of diseases with immunologic defects and/or viral causation. Ebola virus specifically inhibits the dsRNA within cells via a sequestration process. Such RNA would otherwise cause a robust antiviral response to be mounted: Ampligen may be able to overcome this deficiency in host response. Positive results against Ebola in vitro have been reported to the Company by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) and other research/academic institutions in the US and abroad. Clinical protocol development is being pursued. Clinical trial data will be necessary to establish human efficacy of Ampligen® for Ebola viruses.

About U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID)

USAMRIID's mission is to provide leading edge medical capabilities to deter and defend against current and emerging biological threat agents. Research conducted at USAMRIID leads to medical solutions—vaccines, drugs, diagnostics, and information—that benefit both military personnel and civilians. The Institute plays a key role as the lead military medical research laboratory for the Defense Threat Reduction Agency's Joint Science and Technology Office for Chemical and Biological Defense. USAMRIID is a subordinate laboratory of the U.S. Army Medical Research and Materiel Command.

About Hemispherx Biopharma

Hemispherx Biopharma, Inc. is an advanced specialty pharmaceutical company engaged in the manufacture and clinical development of new drug entities ("biological modifiers") for treatment of seriously debilitating disorders especially life-threatening viruses. Hemispherx's flagship products include Alferon® N Injection® and the experimental therapeutics Ampligen® and Alferon® LDO. Ampligen® 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 including cancers. Because both Ampligen® 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 Injection® approval in Argentina includes the use of Alferon N Injection® (under the 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.

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 production of new Alferon® API inventory will not commence until validation phases are complete. While the facility is approved by FDA under the Biological License Application ("BLA") for Alferon®, this status will need to be reaffirmed upon the completion of the facility's enhancements prior to commercial sale of newly produced inventory product. 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. 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. 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. For instance, the strategies and operations of Hemispherx involve risk of competition, changing market conditions, changes 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. The final results of these efforts could vary materially from Hemispherx's expectations. Findings from animal studies may not correlate with results from humans. Clinical trial data will be necessary to establish human efficacy of Ampligen® or Alferon® for Ebola virus disease.

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, above, 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. No evidence is suggested that Alferon® N, Alferon® LDO and/or Ampligen will ever be commercially approved for the new potential treatment indications mentioned in this release.



            

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