Soligenix Announces Publication of Successful Application of its Heat Stabilization Technology to a Human Papillomavirus Vaccine

Princeton, NJ – June 2, 2015 – Soligenix, Inc. (OTCQB: SNGX) (Soligenix or the Company), a late-stage biopharmaceutical company developing products that address unmet medical needs in the areas of inflammation, oncology and biodefense, announced today the publication of data by the University of Colorado demonstrating a heat stable vaccine formulation of a human papillomavirus (HPV) vaccine.  The work was conducted at the University of Colorado, Boulder by Drs. Randolph and Garcea and demonstrated the successful conversion of a commercial virus-like particle (VLP) based vaccine requiring cold-chain storage to a subunit, alum-adjuvanted, vaccine which is stable at ambient temperatures.  This work, funded by a University of Colorado Seed grant and the Specialized Program of Research Excellence (SPORE) in cervical cancer, is the first demonstration of the utility of Soligenix’s ThermoVax™ technology, licensed from the University of Colorado, for the development of a subunit based commercial vaccine.  ThermoVax™ has been previously demonstrated to enhance thermostability of both a ricin vaccine (RiVax™) and an anthrax vaccine (VeloThrax™), demonstrating stability of up to one year at 40 degrees Celsius (104 degrees Fahrenheit) or 16 weeks at 70 degrees Celsius (158 degrees Fahrenheit), respectively.  In this work, the new HPV vaccine formulation was found to be stable for at least 12 weeks at 50 degrees Celsius (122 degrees Fahrenheit), consistent with previous findings.  The results were published online in the European Journal of Pharmaceutics and Biopharmaceutics and are available at:http://www.sciencedirect.com/science/article/pii/S0939641115002416.Soligenix has been developing its heat stabilization technology, ThermoVax™, for use in a variety of vaccine applications, including both biodefense and infectious disease.  This is the first demonstration of the compatibility of the technology with commercial vaccine indications.  In previous studies, vaccination with thermostabilized RiVax™, using the ThermoVax™ technology, protected all animals from acute lethal death due to aerosolized ricin exposure, in contrast to unvaccinated animals that all died within 40 hours.  Importantly, the neutralizing antibody profile produced by the vaccinated NHPs, which were subsequently completely protected against aerosol exposure, matched the profile found in samples from humans previously vaccinated with the RiVax™ vaccine.

In the current study, mice immunized with the ThermoVax-stabilized HPV subunit vaccine were also found to achieve immune responses similar to the commercial HPV vaccine, Cervarix®, as measured by either total antibody levels or neutralizing antibody levels.  Moreover, whereas the immune responses to Cervarix® were drastically reduced after storage for 12 weeks at 50 degrees Celsius, the ThermoVax™ formulated vaccine retained its efficacy. The University of Colorado has filed patent applications for this novel HPV vaccine. Soligenix has not licensed or acquired any rights to these HPV vaccine patent applications filed by the University of Colorado.

“The use of subunit vaccines has always been hindered by concerns about thermostability.  The use of this technology, invented at the University of Colorado, clearly overcomes these concerns and offers broad applicability in many commercial indications.  In addition to the cost-savings incurred for vaccines for the developed world, the use of this technology also offers the opportunity for more effective vaccination in the developing world,” stated Theodore W. Randolph, PhD, Gillespie Professor and Co-Director of the Center for Pharmaceutical Biotechnology and Professor, Department of Chemical and Biological Engineering, University of Colorado, Boulder.

“This is the first application of ThermoVax™, our proprietary thermostabilization system, with a commercial vaccine indication.  This work illustrates the broad applicability of this technology platform,” stated Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix. “We are continuing to develop ThermoVax™ in the context of our RiVax™ vaccine under a recent NIAID contract award of up to $24.7M over 6 years.”

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 as much as 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 with the fewest number of vaccinations.  RiVax™ is extremely labile in 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 has been developed to date 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 Human Papillomavirus (HPV)

Human papillomavirus is one of the most commonly found sexually transmitted infections and has been associated with the majority of incidences of diagnosed cervical cancer (http://www.cdc.gov/std/hpv/stdfact-hpv.htm).  It is also associated with head and neck cancer and other genital tumors.  Vaccines for HPV are commercially available (Cervarix® and Gardasil®) and are recommended for young girls and boys for the prevention of infection and therefore prevention of cancer.  There is no test to determine an individual’s exposure to HPV.

HPV –derived cancers are also very common in the developing world where prevention with commercially available vaccines is more difficult due to the requirement for cold-chain storage for the commercial vaccines.

About Soligenix, Inc. 

Soligenix is a late-stage biopharmaceutical company developing products that address unmet medical needs in the areas of inflammation, oncology and biodefense. Our BioTherapeutics business segment is developing SGX301 as a first-in-class photo-dynamic therapy utilizing safe visible light for the treatment of cutaneous T-cell lymphoma, proprietary formulations of oral beclomethasone 17,21-dipropionate (BDP) for the prevention/treatment of gastrointestinal (GI) disorders characterized by severe inflammation including pediatric Crohn’s disease (SGX203) and acute radiation enteritis (SGX201), and our novel innate defense regulator technology (SGX942) for the treatment of oral mucositis.

Our Vaccines/BioDefense business segment includes active development programs for RiVax™, our ricin toxin vaccine candidate, VeloThrax™, our anthrax vaccine candidate, OrbeShield™, our GI acute radiation syndrome therapeutic candidate and SGX101 and SGX943, our melioidosis therapeutic candidates. The development of our vaccine programs incorporates the use of our proprietary heat stabilization platform technology, known as ThermoVax™.  Currently, this business segment is supported with up to $57 million in government grant and contract funding from the National Institute of Allergy and Infectious Diseases (NIAID) and the Biomedical Advanced Research and Development Authority (BARDA).  Additionally, Soligenix has an exclusive worldwide collaboration with Intrexon Corporation (NYSE: XON) focused on the joint development of SGX101 for the treatment for melioidosis.

For further information regarding Soligenix, Inc., please visit the Company’s website atwww.soligenix.com.

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