Benzinga | Aug 23, 2021 07:34AM EDT

Soligenix Announces Publication Demonstrating Successful Formulation and Heat Stabilization of Filovirus Vaccine Platform for Ebola and Marburg Virus Diseases

Soligenix, Inc. (NASDAQ:SNGX) (Soligenix or the Company), a late-stage biopharmaceutical company focused on developing and commercializing products to treat rare diseases where there is an unmet medical need, announced today a publication describing the formulation of single-vial platform presentations of monovalent (single antigen), bivalent (two antigens) and trivalent (three antigens) combinations of filovirus vaccine candidates. In collaboration with University of Hawaii at Mnoa (UHM) and University of Colorado (UC) co-authors, the manuscript entitled "Single-Vial Filovirus Glycoprotein Vaccines: Biophysical Characteristics and Immunogenicity after Co-lyophilization with Adjuvant", has been published in Vaccine.

The antigens and adjuvants used in this study have been previously demonstrated to protect non-human primates (NHPs) from subsequent infection. Lyophilization of the antigens within monovalent vaccine formulations has also been demonstrated to thermostabilize the antigens at temperatures as high as 40 degrees Celsius (104 degrees Fahrenheit) for up to 12 weeks, enabling storage at ambient temperature. No currently licensed lyophilized vaccine that contains adjuvant is presented in a single-vial format and there are few reports of successfully using nano-emulsions in these lyophilized formulations. The published paper describes the use of a single-vial platform to co-lyophilize antigen(s) and a nano-emulsion adjuvant, CoVaccine HT(tm), maintaining key adjuvant stability characteristics including particle size and colloidal stability. Further, antibody responses previously shown for monovalent vaccines were maintained in both mice and NHPs for the trivalent single-vial co-lyophilized vaccine candidates. Most recently, one of these trivalent formulations has also been shown to protect 75% of vaccinated NHPs against subsequent Sudan ebolavirus challenge, with further development to test efficacy against other filovirus infections ongoing.

"Filoviruses such as Zaire ebolavirus, Sudan ebolavirus and Marburg marburgvirus are some of the most lethal viruses known, and they are endemic in areas of the world where the power supply and distribution network can be uncertain. A thermostabilized vaccine in a single-vial format would significantly enhance any public health response to a new outbreak, at its source," stated Axel Lehrer, PhD, Associate Professor, Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine (JABSOM), UHM. "Our work to date has demonstrated the feasibility of rapid and efficient manufacturing, as well as the ability to thermostabilize multiple antigens that can then be stored at temperatures exceeding 100 degrees Fahrenheit. Having a vaccine platform available such as this has the potential to accelerate worldwide vaccination campaigns addressing future health emergencies, including another global pandemic like the one we are unfortunately experiencing with COVID-19."

"Our combined vaccine platform includes three major components: a robust protein manufacturing process that has been demonstrated on multiple protein antigens, a novel nano-emulsion adjuvant which induces broad immunity and a formulation procedure which enables thermostabilization of the combination of adjuvant and antigen in a single vial," stated Oreola Donini, PhD, Senior Vice President and Chief Scientific Officer of Soligenix. "Elements of this vaccine platform have been utilized in our ricin toxin, filovirus and COVID-19 vaccine candidates, indicating its broad applicability. The ability to package the vaccine candidates in a single-vial platform further adds to their developability, whether as a multivalent or individual monovalent vaccine, particularly against Marburg marburgvirus and Sudan ebolavirus where there are currently no available vaccines."

Under the Company's Public Health Solutions business segment, ongoing collaborations with Dr. Lehrer, as well as work conducted by Theodore Randolph, PhD, Professor, Center for Pharmaceutical Biotechnology, Department of Chemical and Biological Engineering at the University of Colorado, Boulder have demonstrated the feasibility of developing thermally-stable subunit protein vaccine formulations for filoviruses. The thermostabilized filovirus vaccine program is continuing to advance with the support of a National Institute of Health (NIH) grant R01-AI132323 (awarded to the University of Hawaii) and a Small Business Innovation Research grant (#1R44AI157593-01; awarded to Soligenix, Inc.). Work to date has demonstrated the compatibility of lyophilizing both antigen and adjuvant in the same vial, with reconstitution with sterile water for injection immediately prior to use. This simple delivery format, as well as the compatibility with ambient storage, enables vaccines that significantly reduce the logistical hurdles that have been required for addressing the current pandemic or deployment of other Ebola virus vaccines in recent outbreaks in Central and West Africa.