DOR BioPharma licensed anthrax toxin analogues for prospective use in vaccines from Harvard College. The one-year exclusive option encompasses an issued U.S. patent that covers engineered variants of protective antigen (PA) developed in the Harvard Medical School laboratory of John Collier. PA is the principal determinant of protective immunity to anthrax and is being developed for second- and third-generation anthrax vaccines.
Several protein variants developed by Dr. Collier have been shown to be more immunogenic than native rPA, according to the company. This is perhaps because they are processed more efficiently by cellular antigen processing pathways, DOR continues. The firm believes that it will be able to develop Dr. Collier’s anthrax vaccine with an improved stability profile, an issue that has proven challenging in the development of other anthrax vaccines.
“Access to the engineered anthrax PA variants as candidate vaccines makes an excellent fit into our biodefense portfolio and should allow us to make key strides in our biodefense development initiatives,” states Christopher J. Schaber, Ph.D., president and CEO. “We believe that the engineered PA variants can be used in platform technologies for delivery of single-use or combination biodefense vaccines and will be useful for generating stable vaccines that induce antibodies in fewer doses than the conventional AVA vaccine or other rPA vaccines currently under development.”
DOR’s biodefense products in development are recombinant subunit vaccines designed to protect against the effects of exposure to ricin toxin, botulinum toxin, and anthrax.