DOR BioPharma Initiates Dosing of RiVax in Phase I Clinical Trial

DOR BioPharma and its academic partner have begun human testing of RiVax, a recombinant vaccine designed to protect against ricin toxin.

After having successfully passed prerequisite animal safety and efficacy evaluations, RiVax (recombinant ricin toxin vaccine) is the first ricin vaccine to be tested in humans. The Phase I trial is a dose-escalating trial in which volunteers will receive three monthly intramuscular doses of vaccine. Three cohorts of five volunteers each will receive low, medium or high doses of RiVax. The five volunteers receiving the lowest dose of vaccine (10 mcg) will be monitored for adverse side effects before receiving the next injection.

The safety outcomes in each of the volunteers will be evaluated one month following the first injection before proceeding to the next dose level. The last cohort of volunteers will receive 100 mcg of RiVax. Blood from the volunteers will be tested for ricin neutralizing antibodies prior to each injection and regularly for six months, with the final measure of immunogenicity/effectiveness one year after the first injection.

The trial is designed to confirm that the vaccine is safe at doses that induce ricin-neutralizing antibodies. The company expects that preliminary interim safety and immunogenicity data will be available as early as the second quarter of 2005.