PARIS ¿ The French drug-delivery company Biovector Therapeutics SA has signed separate feasibility agreements with Chiron Corp., of Emeryville, Calif., and Bayer Corp., of Pittsburgh, for the assessment of Biovector¿s proprietary DNA delivery technology platforms in DNA vaccine applications and the expression of blood-circulating proteins, respectively.

Chiron will conduct a 12-month to 15-month study testing Biovector¿s Neutraplex system in novel DNA-based vaccines, and Bayer will assess the ability of Biovector¿s Lipoplex systems to allow functional circulating protein expression (Factor VIII). The objective of the latter, six-month study is to obtain long-lasting expression at high enough rates to permit the development of new treatments for hemophilia.

Biovector¿s Lipoplex system is formed by combining lipids and plasmid DNA, giving them an organizational structure similar to a virus. The company has two types of Lipoplex systems ¿ one of which, the DLS, it licensed from the National Institutes of Health, and the other, the Neutraplex, it developed itself. Both these patented vectors may be administered by intramuscular or intravenous injection, and can freely circulate within the organism.

Altogether, Biovector, which is based near Toulouse, in southwestern France, has patented four families of proprietary systems for the delivery of active ingredients or therapeutic genes, and is using them mainly for developing modern vaccines in partnership with pharmaceutical companies. The company will have four products in clinical development by the fourth quarter of 1999, having completed its first Phase I trial last October.

Biovector¿s president and CEO, Emile Loria, said that, in addition to these feasibility studies, Biovector is funding several research programs on DNA delivery at university laboratories, which ¿could lead to exclusive licenses and enlargement of our product portfolio.¿ The company is collaborating with the University of Zurich, in Switzerland, on the development of a DNA vaccine for influenza, and with the Institute of Human Virology at the University of Maryland on the development of a DNA vaccine for HIV, using the Lipoplex vector. This program is expected to result in a highly reproducible in vivo delivery system.

In addition, a collaboration with the University of Michigan gives Biovector access to a large number of plasmid constructions corresponding to circulating proteins (Factor IX).