- RiVax®-Vaccinated NHP survival was statistically significantly correlated with an epitope-specific serum assay ("EPICC") prior to challenge
- Correlates of protection are essential to support approval via the FDA "Animal Rule"
PRINCETON, N.J., Dec. 20, 2022 /PRNewswire/ -- 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 publication of preclinical immunogenicity challenge studies for RiVax® (heat stable ricin toxin vaccine) demonstrating statistically significant correlates of protection predicting survival after lethal aerosolized ricin challenge in non-human primates (NHPs). The article titled "Serum antibody profiling identifies vaccine-induced correlates of protection against aerosolized ricin toxin in rhesus macaques" has been accepted for publication in the journal npj Vaccines (available here). The article results from collaborative work lead by the Wadsworth Center of the New York State Department of Health. This same thermostabilization approach is also being advanced in the development of Soligenix's CiVax™ vaccine for COVID-19 and SuVax™ and MarVax™ vaccines for ebola type filovirus infections.
"These published results identifying correlates of protection between NHPs and humans are essential to advancing RiVax® under the U.S. Food and Drug Administration (FDA) Animal Rule," stated Oreola Donini, PhD, Senior Vice President and Chief Scientific Officer of Soligenix. "This, and other ongoing work, has continued to corroborate the efficacy of RiVax® and will facilitate its potential approval."
RiVax® is the Company's vaccine candidate for the prevention of death following exposure to a lethal dose of ricin toxin using a unique antigen that is completely devoid of the toxic activity of ricin. Formulated by Soligenix to have enhanced thermostability, RiVax® has demonstrated up to 100% protection in mice and NHPs subsequently exposed to lethal doses of ricin toxin either systemically or by aerosol. RiVax® has been demonstrated to be stable for at least 12 months of storage at temperatures up to 40 degrees Celsius (104 degrees Fahrenheit). Moreover, mice have been shown to be protected from ricin challenge at 10 times the lethal dose for at least 12 months post-vaccination. These results, coupled with the recent demonstration of statistically significant correlates of protection via the EPICC assay, position RiVax® for additional clinical and pivotal non-clinical studies under the FDA Animal Rule.
About RiVax®RiVax® is Soligenix's proprietary heat stable recombinant subunit vaccine developed to protect against exposure to ricin toxin, the threat of which has been highlighted in the news with an envelope addressed to President Trump that was thought to contain this potent and potentially lethal toxin. With RiVax®, Soligenix is a world leader in the area of ricin toxin vaccine research.
RiVax® contains a genetically altered version of a Ricin Toxin A (RTA) chain containing two mutations that inactivate the toxicity of the ricin molecule which was originally invented at the University of Texas Southwestern. Phase 1 clinical studies to date have demonstrated the safety of the antigen and adjuvant, as well as the generation of ricin neutralizing antibodies which are increased in the presence of the alum adjuvant. In animal studies, the alum formulation of RiVax® also induced higher titers and longer-lasting antibodies than the adjuvant-free vaccine. Vaccination with the thermostabilized alum-adjuvanted RiVax® formulation in a NHP animal model provided 100% protection (p