Soligenix Announces Issuance of US Patent for its ThermoVax™ Technology

Princeton, NJ – May 22, 2013 – Soligenix, Inc. (OTCQB: SNGX) (Soligenix or the Company), a clinical stage biopharmaceutical company focused on developing products to treat inflammatory diseases and biodefense countermeasures where there remains an unmet medical need, announced today that the US Patent and Trademark Office granted patent 8,444,991 entitled “Method of Preparing an Immunologically-Active Adjuvant-Bound Dried Vaccine Composition.”  The new patent’s claims encompass composition of matter and method claims for ThermoVax™, the vaccine thermostabilization technology exclusively licensed to Soligenix by the University of Colorado.

The main patent claims describe methods of preparing an immunologically-active adjuvant-bound, thermostable, freeze dried vaccine composition in which the vaccine utilizes conventional adjuvants comprised of aluminum salts, as well as claims covering the adjuvant-bound composition itself.  Aluminum salts are commonly used as adjuvants in many vaccines, including those administered to children. ThermoVax™ was developed specifically to overcome the problems that are encountered with freeze-drying vaccines that contain aluminum adjuvants while simultaneously engineering them to withstand extremes of temperature.

“The granting of the thermostabilization patent is a significant milestone for the ThermoVax™ program and is a critical component in our commercialization strategy for vaccines that can avoid the increased costs and logistical burdens associated with cold chain storage and distribution,” stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix. “We expect that the introduction of an effective technology for long-term stabilization of vaccines has the potential to be a major advance in the national effort to develop effective countermeasures and therapies for significant biothreats and emerging pathogens. We have initiated discussions with a number of vaccine companies and non-profit organizations regarding the potential for collaboration on heat stable versions of their vaccine candidates.”

About ThermoVax™

ThermoVax™, is a novel method of rendering aluminum salt (known colloquially as Alum), adjuvanted vaccines stable at elevated temperatures. Alum is the most widely employed adjuvant technology in the vaccine industry. The value of ThermoVax™ lies in its potential ability to eliminate the need for cold-chain production, transportation, and storage for Alum adjuvanted vaccines. This would relieve companies of the high costs of producing and maintaining vaccines under refrigerated conditions.  Based on historical reports from the World Health Organization and other scientific reports, a meaningful proportion of vaccine doses globally are wasted due to excursions from required cold chain temperature ranges. This is due to the fact that most aluminum adjuvanted vaccines need to be maintained at between 2 and 8 degrees Celsius and even brief excursions from this temperature range (especially below freezing) usually necessitates the destruction of the product or the initiation of costly stability programs specific for the vaccine lots in question.  The savings realized from the elimination of cold chain costs and related product losses would in turn significantly increase the profitability of vaccine products. Elimination of the cold chain would also further facilitate the use of these vaccines in the lesser developed parts of the world. ThermoVax™ has the potential to facilitate easier storage and distribution of strategic national stockpile vaccines in emergency settings.

ThermoVax™ development is being supported pursuant to our $9.4 million NIAID grant enabling development of thermo-stable ricin (RiVax™) and anthrax (VeloThrax™) vaccines. Proof-of-concept preclinical studies with ThermoVax™ indicate that it is able to produce stable vaccine formulations using adjuvants, protein immunogens, and other components that ordinarily would not withstand long temperature variations exceeding customary refrigerated storage conditions. These studies were conducted with our aluminum-adjuvanted ricin toxin vaccine, RiVax™, made under precise lyophilization conditions using excipients that aid in maintaining native protein structure of the ricin A chain, the immunogenic compound of the vaccine. When RiVax™ was kept at 40 degrees Celsius for six months, all of the animals vaccinated with the lyophilized RiVax™ vaccine developed potent and high titer neutralizing antibodies. Confirmatory results have extended the stability to six months when the vaccine is kept at 40 degrees Celsius. In contrast, animals that were vaccinated with the liquid RiVax™ vaccine kept at 40 degrees Celsius did not develop neutralizing antibodies and were not protected against ricin exposure. The ricin A chain is extremely sensitive to temperature and rapidly loses the ability to induce neutralizing antibodies when exposed to temperatures higher than 8 degrees Celsius.

The underlying lyophilization technology was discovered by Drs. John Carpenter and Theodore Randolph at the University of Colorado, the inventors of the technology underlying the ThermoVax™ products.  The vaccine technology is being developed with support from NIH/NIAID under cooperative grant agreement U01 AI 082210.

About Soligenix, Inc.

Soligenix is a clinical stage biopharmaceutical company developing products to treat serious gastrointestinal diseases where there remains an unmet medical need, as well as developing several biodefense vaccines and therapeutics. Soligenix is developing proprietary formulations of oral BDP (beclomethasone 17,21-dipropionate) for the prevention/treatment of gastrointestinal disorders characterized by severe inflammation, including pediatric Crohn’s disease (SGX203), acute radiation enteritis (SGX201) and chronic Graft-versus-Host disease (orBec®), as well as developing its novel innate defense regulator (IDR) technology for the treatment of oral Mucositis (SGX942).

Through its BioDefense Division, Soligenix is developing countermeasures pursuant to the Biomedical Advanced Research and Development Authority (BARDA) Strategic Plan of 2011-2016 for inclusion in the US government’s Strategic National Stockpile. Soligenix’s lead biodefense products in development are a recombinant subunit vaccine called RiVax™, which is designed to protect against the lethal effects of exposure to ricin toxin and VeloThrax™, a vaccine against anthrax exposure. RiVax™ has been shown to be well tolerated and immunogenic in two Phase 1 clinical trials in healthy volunteers. Both RiVax™ and VeloThrax™ are currently the subject of a $9.4 million National Institute of Allergy and Infectious Diseases (NIAID) grant supporting development of Soligenix’s new vaccine heat stabilization technology known as ThermoVax™. Soligenix is also developing OrbeShield™ for the treatment of gastrointestinal acute radiation syndrome (GI ARS) under a $600,000 NIAID Small Business Innovation Research (SBIR) grant. OrbeShield™ has previously demonstrated statistically significant preclinical survival results in two separate canine GI ARS studies funded by the NIH. Recently, Soligenix announced a worldwide exclusive collaboration with Intrexon Corporation that will focus on the joint development of a treatment for Melioidosis, a high priority biothreat and an area of unmet medical need.

For further information regarding Soligenix, Inc., please visit the Company’s Website at www.soligenix.com.

This press release contains forward-looking statements that reflect Soligenix, Inc.’s current expectations about its future results, performance, prospects and opportunities. Statements that are not historical facts, such as “anticipates,” “believes,” “intends,” “potential,” or similar expressions, are forward-looking statements. These statements are subject to a number of risks, uncertainties and other factors that could cause actual events or results in future periods to differ materially from what is expressed in, or implied by, these statements. Soligenix cannot assure you that it will be able to successfully develop or commercialize products based on its technology, particularly in light of the significant uncertainty inherent in developing vaccines against bioterror threats conducting preclinical and clinical trials of vaccines, obtaining regulatory approvals and manufacturing vaccines, that product development and commercialization efforts will not be reduced or discontinued due to difficulties or delays in clinical trials or due to lack of progress or positive results from research and development efforts, that it will be able to successfully obtain any further funding to support product development and commercialization efforts,  including  grants and awards, maintain its existing grants which are subject to performance, enter into any biodefense procurement contracts with the US Government or other countries, that it will be able to compete with larger and better financed competitors in the biotechnology industry, that changes in health care practice,  third party reimbursement limitations and Federal and/or state health care reform initiatives will not negatively affect its business,  or that the US Congress may not pass any legislation that would provide additional funding for the Project BioShield program.  In addition, our near and long-term prospects depend on our ability to obtain and maintain patents, protect trade secrets and operate without infringing upon the proprietary rights of others. We could incur substantial costs in litigation if we are required to defend ourselves in intellectual property infringement suits brought by third parties, with or without merit, or if we are required to initiate litigation against others to protect or assert our intellectual property rights,  and we may not be successful in defending our proprietary rights in such litigation  These and other risk factors are described from time to time in filings with the Securities and Exchange Commission, including, but not limited to, Soligenix’s reports on Forms 10-Q and 10-K. Unless required by law, Soligenix assumes no obligation to update or revise any forward-looking statements as a result of new information or future events.