Soligenix, Inc., 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, has reported 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 programme 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."

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.

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 Dr John Carpenter and Dr 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.