Vaccine for Ricin to Counter Bioterrorism Use

An exclusive option to license pending patent applications pertaining to the use of novel recombinant ricin A chain mutants as vaccines to protect against aerosolized ricin has been announced by Dor BioPharma, Inc. (Lake Forest, IL, USA). The exclusive option covers the development of intranasal, oral, and inhalable vaccines that can be developed using the proprietary nontoxic mutants of ricin.

Ricin is the second-most potent toxin known. If deployed as a bioterrorist weapon by aerosolization, there is no effective antidote or vaccine approved for human use. Lung damage from inhalation is quick and irreversible. Only recently, an antiterrorist sweep in London found small quantities of ricin among the material of suspects. A novel ricin vaccine has been developed in the laboratory of Dr. Ellen Vitetta, director of the Cancer Immunobiology Center at the University of Texas Southwestern Medical Center (Dallas, USA). Investigators from the US Army Medical Research Institute of Infectious Diseases found that the orally delivered encapsulated ricin toxoid was capable of protecting 100% of animals against lethal challenge to ricin toxin by subsequent inhalation. The results were published in Vaccine.

Further development by Dor will aim towards optimizing an effective formulation. This will be delivered by the oral or intranasal route, using Dor's proprietary Microvax polymer microspheres that encapsulate antigens and usher them into lymphoid tissue in the intestine or nasopharynx. "We envision the development or ricin vaccines using a totally nontoxic portion of ricin as the safest and best choice to combat the potential use of ricin toxin in terrorist attacks or its use on the battlefield.”




Related Links:
Dor BioPharma
Univ. of Texas Southwestern Medical Center