BioterrorismSoligenix receives European, Canadian patents for its ricin toxin vaccine (RiVax) formulation

Published 13 July 2018

Soligenix, Inc., a late-stage biopharmaceutical company, announced that it has received notice of allowance for European and Canadian patent applications further extending protection around ThermoVax  including coverage of the company’s ricin toxin vaccine, RiVax. RiVax potentially would be added to the Strategic National Stockpile and dispensed in the event of a terrorist attack.

Soligenix, Inc., a late-stage biopharmaceutical company, announced that it has received notice of allowance for European and Canadian patent applications further extending protection around ThermoVax  including coverage of the company’s ricin toxin vaccine, RiVax. ThermoVax is a proprietary vaccine heat stabilization platform technology and the patent, titled “Thermostable vaccine compositions and methods of preparing same,” has been previously allowed in Japan, Australia and New Zealand with applications pending in China, United States, and other jurisdictions.

The company notes that the issued patent is complementary to previous patents, including U.S. patents 8,444,991 granted on 21 May 2013 and 8,808,710 granted on 19 August 2014, which include claims for methods of making stabilized vaccines and their attendant compositions. In this new patent, the main claims cover formulations of Soligenix’s proprietary thermostabilized ricin toxin vaccine, RiVax. The thermostable formulation of RiVax has been shown to be stable for at least 12 months at temperatures up to 40 degrees Celsius (104 degrees Fahrenheit) and to provide 100 percent protection to non-human primates exposed to aerosol ricin challenge in preclinical studies.

Recent developments in the RiVax program have also described immune correlates of protection for the ricin toxin vaccine, which are important to facilitating potential approval of thermostabilized RiVax via the U.S. Food and Drug Administration (FDA) “Animal Rule.” As a biodefense vaccine, RiVax also has the potential to qualify for a priority review voucher (PRV) upon FDA approval. Recent PRVs have sold for as much $350 million.

“Soligenix continues to advance its RiVax program with funding from the U.S. government.” stated Christopher J. Schaber, President and Chief Executive Officer of Soligenix. “Soligenix is a world leader in ricin toxin vaccine development, with a Phase 2 clinical trial planned to begin this year.”

About ricin toxin
Ricin toxin is a lethal plant-derived toxin and potential biological weapon because of its stability and high potency, and the fact it is readily extracted from by-products of castor oil production. Ricin comes in many forms including powder, mist or pellet. Ricin can also be dissolved in water and other liquids. The U.S. Centers for Disease Control and Prevention estimates that the lethal dose in humans is about the size of a grain of salt. Ricin toxin illness causes tissue necrosis and general organ failure leading to death within several days of exposure. Ricin is especially toxic when inhaled. Ricin works by entering cells of the body and preventing the cells from making