Soligenix Announces Positive One-Year High-Temperature Stability Results with ThermoVax™ Vaccine Heat Stabilization Technology

Princeton, NJ – January 15, 2014 – Soligenix, Inc. (OTCQB: SNGX) (Soligenix or the Company), a clinical stage biopharmaceutical company focused on developing products to treat serious inflammatory diseases where there remains an unmet medical need, as well as developing several biodefense vaccines and therapeutics, announced today significant steps forward in the development of ThermoVax™, its proprietary vaccine thermostabilization platform technology.  Recent studies have demonstrated the potential for heat-sensitive vaccines formulated using this technology to withstand temperatures exceeding 40 degrees Celsius (104 degrees Fahrenheit) for up to one year. The underlying work has been conducted with the Company’s proprietary ricin toxin vaccine (RiVax™) as part of a continuing program to evaluate the effectiveness of protein subunit vaccines to withstand extremes of temperature and other environmental stress conditions. These studies amplify and extend former evaluations that indicated retention of potency for at least six months at temperatures as high as 40 degrees Celsius, outside the range of typical vaccine storage conditions.  The research and development of ThermoVax™ is currently being supported by a $9.4 million National Institute of Allergy and Infectious Disease (NIAID) grant to Soligenix for biodefense vaccines to prevent ricin toxin and anthrax exposure.

These results underline the potential for long-term stability of subunit vaccines stored under ambient conditions or at high temperatures. Vaccines are almost always stored refrigerated because of vulnerability to heat exposure, resulting in loss of potency and efficacy. By employing ThermoVax™ during final formulation of RiVax™, which is extremely unstable in its liquid form, a stable and potent vaccine is produced that is capable of withstanding temperatures at least as high as 40 degrees Celsius for up to one year.  The most recent studies, which employed a combination of sensitive techniques to evaluate the structure of the vaccine and the resulting immunogenicity, demonstrated that the vaccine retained original levels of potency after one year of storage at 40 degrees Celsius. RiVax™, formulated with ThermoVax™, has the potential to facilitate easier storage and distribution in a national stockpile for emergency situations.

In addition to RiVax™, the Company has previously reported that its proprietary anthrax vaccine, VeloThrax™, formulated with ThermoVax™ and subsequently exposed to temperatures as high as 70 degrees Celsius (158 degrees Fahrenheit) for at least one month, retained full potency in animals as well as other characteristics such as receptor binding indicative of full structural integrity. The combination of ThermoVax™ and VeloThrax™ along with a potent secondary adjuvant resulted in rapid onset of antibodies correlated to protection against anthrax in animal models.  Additional studies have confirmed longer term stability of VeloThrax™ at 40 degrees Celsius for up to four months.

“The success attained thus far with both ThermoVax™ formulated RiVax™ and ThermoVax™ formulated VeloThrax™ further demonstrates the robustness and broad applicability of the ThermoVax™ technology,” stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix.  “We believe that ThermoVax™ could be applied to a wide variety of vaccines and adjvuants to eliminate the need for refrigeration and cold chain distribution.

Dr. Schaber continued, “We believe ThermoVax™ is a significant step forward in vaccine technology and has the potential to lead to major cost savings in the distribution and storage of currently marketed vaccines and could further facilitate their use in the developing world.  We remain excited about the potential utility of the ThermoVax™ platform and 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 technology that is designed to eliminate the standard cold chain production, distribution and storage logistics required for most vaccines. Cold chain requirements add considerable cost to the production and storage of current conventional vaccines. According to the Biopharma Cold Chain Sourcebook of 2010, 98% of all vaccines (with a total value of $20.6 billion) require shipment through cold chain. Elimination of the cold chain would also enhance the utility of these vaccines for emerging markets and for other applications requiring but lacking reliable cold chain capabilities. Further, the World Health Organization (WHO) reports that 50% of all global vaccine doses are wasted because they are not kept within required temperature ranges. NIAID has also highlighted the priority of technologies for biodefense vaccines that focus on broad spectrum approaches including vaccine adjuvants and temperature stabilization for long shelf life, rapid onset of immunity, and surge capacity for production.  For vaccines that are intended for long-term stockpiling, such as for use in biodefense or in pandemic situations, the utilization of ThermoVax™ has the potential to facilitate easier storage and distribution of strategic national stockpile vaccines in emergency situations.

The technology utilizes precise lyophilization of protein immunogens with conventional aluminum adjuvants in combination with secondary adjuvants for rapid onset of protective immunity where protective immunity is desired with the fewest number of vaccinations.  RiVax™ and Velothrax™ are extremely labile in their liquid form requiring careful management under refrigerated conditions at 4 degrees Celsius (39 degrees Fahrenheit).  By employing ThermoVax™ during their final formulation, it is possible to produce stable and potent vaccines that are capable of withstanding temperatures at least as high as 40 degrees Celsius (104 degrees Fahrenheit) for up to one year.

The underlying technology has been developed by Drs. John Carpenter and Theodore Randolph at the University of Colorado. The vaccine technology is being developed in collaboration with SRI International, the University of Kansas, the Wadsworth Center of the New York State Department of Health, and the Tulane National Primate Research Center under the sponsorship of the cooperative grant from NIAID.

About Soligenix, Inc.

Soligenix is a clinical stage biopharmaceutical company developing products to treat serious inflammatory 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 SGX942 for the treatment of oral mucositis.

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 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 BARDA contract award valued up to $26.3 million and a NIAID contract award valued up to $6.4 million. OrbeShield™ has previously demonstrated statistically significant preclinical survival results in a canine model of GI ARS funded by the NIAID.  Additionally, Soligenix has an exclusive worldwide collaboration with Intrexon Corporation (NYSE: XON) focused 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, including but not limited to, potential market sizes, patient populations and clinical trial enrollment.  Statements that are not historical facts, such as “anticipates,” “estimates,” “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, achieve regulatory approval for or commercialize products based on its technologies, 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 requirements, 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.  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.