Soligenix Demonstrates Positive Proof of Concept with its Proprietary Vaccine Thermostabilization Technology

Soligenix Demonstrates Positive Proof of Concept with its Proprietary Vaccine Thermostabilization Technology

Research Conducted under Existing $9.4 Million NIAID Thermostability Grant

PRINCETON, N.J., Feb. 6, 2012 /PRNewswire/ -- Soligenix, Inc. (Soligenix or the Company), a development stage biopharmaceutical company, announced today results from preclinical studies of its proprietary vaccine thermostabilization technology indicating that Soligenix 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 Soligenix's aluminum-adjuvanted ricin toxin vaccine, RiVaxTM, 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 RiVaxTM was kept at 40 degrees C for over one month, all of the animals vaccinated with the lyophilized RiVaxTM vaccine developed potent and high titer neutralizing antibodies. In contrast, animals that were vaccinated with the liquid RiVaxTM vaccine kept at 40 degrees C 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 C.

These studies were performed by Theodore W. Randolph, PhD, Professor of Pharmaceutical Biotechnology at the University of Colorado Boulder and John Carpenter, PhD, Professor of Pharmaceutical Biotechnology at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of Colorado Anschutz Medical Campus. Dr. Randolph stated, "Early indications from the ongoing stability evaluation of the ricin vaccine stored at elevated temperatures are very encouraging for a protein immunogen that is otherwise so inherently unstable."

"We are very excited about these results as the achievement of extended stability under elevated temperature represents a significant step forward in vaccine technology," stated Robert N. Brey, PhD, Chief Scientific Officer of Soligenix. "These studies successfully establish the proof of concept that our vaccine thermostabilization technology works and now allows for the potential to apply this technology to other conventional vaccines that require refrigeration. Cold chain requirements add considerable cost to the production and storage of current conventional vaccines. Further, lack of long-term stability is a significant problem in vaccines for use in emergency situations and especially for vaccines used in the developing world where the cold storage chain is difficult to maintain. We believe that this technology has the potential to add value to many existing and developing vaccines."

The removal of water from pharmaceutical preparations by lyophilization is often used to confer extended shelf life to therapeutic protein products, but vaccines often lose potency during lyophilization, especially if they are formulated with aluminum salt adjuvants that are commonly used in vaccines. Therefore, most aluminum-adjuvanted vaccines must be refrigerated or frozen because of the sensitivity of vaccine components to room temperature or higher. Soligenix has been developing its thermostabilization technology under a license agreement from the University of Colorado that was initiated to support the technology development efforts funded by a $9.4 million grant from the National Institute of Allergy and Infectious Diseases (NIAID). The license agreement has an expanded scope for thermostable vaccines for biodefense as well as all potential vaccine indications. The novel technology involves the use of several unique process and formulation steps that fix sensitive vaccine ingredients in the correct, native configuration. For biodefense indications, the company is using the stabilization technology to advance RiVaxTM, its subunit vaccine against ricin toxin, as well as its DNI rPA anthrax subunit vaccine. The underlying technology has been developed by Drs. Amber Clausi, John Carpenter and Theodore Randolph at the University of Colorado.

The World Health Organization (WHO) reports that 50% of all global vaccine doses are wasted because vaccines are not kept within required temperature ranges. Aluminum-adjuvanted vaccines usually need to be maintained between 2-8 degrees C and often times even brief excursions from this temperature range (especially those which result in freezing) necessitates the destruction of the product or the initiation of costly long-term stability programs. The savings realized from the elimination of cold chain costs and related product losses would significantly increase the profitability of vaccine products. 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. For vaccines that are intended for long term stockpiling, such as for use in biodefense or in pandemic situations, the utilization of Soligenix's thermostability technology has the potential to facilitate storage and distribution of strategic national stockpile vaccines in emergency settings. It may also enable preparation of otherwise difficult multivalent (protective against multiple pathogens) formulations.

About Soligenix, Inc.

Soligenix is a development stage biopharmaceutical company developing products to treat life-threatening side effects of cancer treatments and serious gastrointestinal diseases, and vaccines for certain bioterrorism agents. Soligenix's lead product, orBec® (oral beclomethasone dipropionate), is a potent, locally acting corticosteroid that has been initially developed for the treatment of acute gastrointestinal Graft-versus-Host disease (GI GVHD), a common and potentially life-threatening complication of hematopoietic cell transplantation. Soligenix is also conducting a National Cancer Institute (NCI)-supported Phase 1/2 clinical trial of SGX201 in the prevention of acute radiation enteritis. Additionally, Soligenix is developing SGX203 for the treatment of pediatric Crohn's disease.

Through its Biodefense Division, Soligenix is developing countermeasures pursuant to the Project BioShield Act of 2004. Soligenix's biodefense products in development are a recombinant subunit vaccine called RiVaxTM, which is designed to protect against the lethal effects of exposure to ricin toxin and SGX204, a vaccine against anthrax exposure. RiVaxTM has been shown to be well tolerated and immunogenic in a Phase 1 clinical trial in normal volunteers. Both RiVaxTM and SGX204 are currently the subject of a $9.4 million National Institute of Allergy and Infectious Disease (NIAID) grant supporting development of new heat stable vaccines. Soligenix is also developing SGX202 for the treatment of gastrointestinal acute radiation syndrome (GI ARS) and has demonstrated positive preliminary preclinical results in a canine GI ARS model.

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," 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, including orBec®, SGX201, SGX202, SGX203, SGX204, RiVaxTM, and LPMTM, particularly in light of the significant uncertainty inherent in developing vaccines against bioterror threats, manufacturing and conducting preclinical and clinical trials of vaccines, and obtaining regulatory approvals, that its cash expenditures will not exceed projected levels, 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 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 the US Congress may not pass any legislation that would provide additional funding for the Project BioShield program, that it will be able to patent, register or protect its technology from challenge and products from competition or maintain or expand its license agreements with its current licensors, or that its business strategy will be successful. Important factors which may affect the future use of orBec® for gastrointestinal GVHD include the Data Safety Monitoring Board's recent determination disclosed in our Form 8-K dated September 15, 2011 recommending that Soligenix stop its confirmatory Phase 3 clinical trial of orBec® in acute GI GVHD and the likelihood that: the FDA will require that Soligenix conduct additional clinical trials to demonstrate the safety and efficacy of orBec® which will take a significant amount of time and money to complete and positive results leading to regulatory approval cannot be assumed; Soligenix is dependent on the expertise, effort, priorities and contractual obligations of third parties in the clinical trials, manufacturing, marketing, sales and distribution of its products; orBec® may not gain market acceptance if it is eventually approved by the FDA; and others may develop technologies or products superior to orBec®. Factors affecting the development and use of SGX201, SGX202, SGX203, SGX204, RiVaxTM and LPMTM are similar to those affecting orBec®. These and other 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.

SOURCE Soligenix, Inc.