Centers for Disease Control Urges Preparation for an Active Seasonal Flu Season

Hemispherx Biopharma Accelerates Program to Evaluate Ampligen(R)/FluMist(R) Combination as Potential Intranasal Influenza Vaccine Against Pandemic Flu Strains


PHILADELPHIA, Dec. 16, 2013 (GLOBE NEWSWIRE) -- Hemispherx Biopharma, Inc. (NYSE MKT:HEB) (the "Company" or "Hemispherx") announced that the company will accelerate its experimental program for a new intranasal influenza vaccine combination following a media briefing by the Centers for Disease Control (CDC) urging Americans, especially young children and the elderly, to get vaccinated for the emerging flu season immediately (CDC, December 12, 2013), coincidental with National Influenza Vaccination Week.

According to the CDC, Flu vaccination prevented an estimated 6.6 million influenza-associated illnesses, 3.2 million medically attended illnesses, and 79,000 hospitalizations during the 2012-2013 flu season," as reported in the Morbidity and Mortality Weekly Report (MMWR). "CDC also reported today that despite the benefits of flu vaccination, only 40% of Americans 6 months and older had reported getting a flu vaccine this season as of early November 2013."

"The estimated benefits of vaccination for the 2012-2013 season are higher than any other season for which CDC has produced similar estimates. These high numbers are attributable to the severity of the season. The report estimates that last season there were a total of 31.8 million influenza-associated illnesses, 14.4 million medically attended illnesses, and 381,000 hospitalizations in the United States."

The CDC also reported that children have already died from the flu this season. While the current approved vaccines are not completely effective against all known seasonal influenza strains, officials said they wouldn't know the effectiveness of the current seasonal vaccines until flu season ends.

Hemispherx recently announced that its Phase 1/2 clinical trial at the University of Alabama Vaccine Research Clinic of intranasally administered Ampligen ® and FluMist ® is now being expanded based on an analysis of safety results to date conducted by both the Food and Drug Administration ("FDA") and a Data Monitoring Committee, the latter group comprised of a team of independent clinical, basic research, and statistical professionals. Ampligen® is an experimental immunotherapeutic and FluMist® is a live attenuated seasonal influenza vaccine.

FluMist®, the only commercially available seasonal influenza vaccine available in the USA for intranasal use, was approved by the FDA in 2003. Given alone, it has (as expected) no known activity against any strains of pandemic influenza. With respect to efficacy in its primary target population (adults age 18-49), FluMist® (given alone) only reduces the febrile illness occurrence rate from 10.9 to 23.7% over placebo treatment (Belshe R et al. 2004, CID 39:920-927). In another study of FluMist intranasal vaccination, 9% of the treated group had a 4-fold or greater increase in the accepted therapeutic surrogate endpoint in serum called "HAI", while thirty-three percent of treated subjects increased potentially protective antibody (IgA) in the nose (Barria M, et al. 2013, JID 207 (1): 115-124 ). Going forward, new experiments ongoing at the University of Alabama are designed to test in populations of healthy young volunteers whether FluMist® administered with Ampligen® can dramatically increase the percentage of responders. 

The ongoing clinical study is the first extension to humans of preclinical studies, previously published in the peer-reviewed literature, indicating that the combination of Ampligen® (an experimental therapeutic) with commercially available seasonal influenza vaccine when applied intranasally, may provide enhanced protection against certain potentially pandemic influenza strains (Ichinohe T, et al. 2007, JID 196:1313-1320).

It is hoped that FluMist® combined with an effective immune adjuvant may be able to provide easily administered protection in humans even against mutated strains of flu virus including both H7N9 and H5N1 strains (please see Hemispherx release dated December 9, 2013). Successful enhancement of immune responses in the current study group of young adults by Ampligen®, an experimental therapeutic, would provide justification for extension of studies to the elderly who, as a group, could benefit greatly from more effective vaccines.

Avian H5N1 and H7N9 viruses are highly pathogenic in humans. Human disease has been limited thus far by the inability of these viruses to infect the upper airways of humans – although there has been concern that viral mutations could provide this capacity. The Company believes that the expanded human trial at the University of Alabama will provide the first data in humans as to whether the epitope expansion observed by Dr. Hasegawa in experimental animals occurs in humans. Successful animal experimentation does not necessarily predict clinical effectiveness and no assurance can be given that the projected clinical tests will demonstrate either acceptable safety or efficacy.

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 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. 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.

Forward-Looking Statements

The foregoing release contains forward-looking statements that can be identified by words such as "will be, investigative, interim, potential" or similar terms, or by express or implied discussions regarding potential efficacy for Hemispherx's Ampligen®, or regarding potential future revenues from Ampligen®. You should not place undue reliance on these statements. Such forward-looking statements are based on the current beliefs and expectations of Management regarding future events, and are subject to significant known and unknown risks and uncertainties. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those set forth in the forward-looking statements. There can be no guarantee that Ampligen® will receive regulatory approval or be commercially successful in the future. In particular, management's expectations regarding Ampligen® could be affected by, among other things, the uncertainties inherent in research and development, including unexpected clinical trial results and additional analysis of existing clinical data and failure of the clinical results to confirm the predictions of the animal studies; unexpected regulatory actions or delays or government regulation generally; the Company's ability to obtain or maintain proprietary intellectual property protection; general economic and industry conditions; global trends toward health care cost containment, including ongoing pricing pressures; unexpected manufacturing issues, and other risks and factors 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 on file with the U.S. Securities and Exchange Commission, and in the Disclosure Notice below. Hemispherx is providing the information in this press release as of this date and does not undertake any obligation to update any forward-looking statements contained in this press release as a result of new information, future events or otherwise.

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 or in other countries. The production of new Alferon® API inventory will not commence until the capital improvement and 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.



            

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