Solutions

NexBio currently has three R&D programs focusing on influenza and other key
respiratory viruses: Fludase®, Inviridin(TM), and Viracidin(TM). All are being
supported by grants from the NIH. Each program is aimed at generating
novel, broad-spectrum influenza therapeutics that may fundamentally solve the
problems of current vaccines and antiviral drugs. Notably, because of their
unique mechanisms, of action these candidates have the potential to be
effective not only against influenza viruses, but against other clinically
important respiratory viruses as well.

Fludase® is a recombinant fusion protein which blocks influenza virus
infection by eliminating the only cell surface receptors available to these
viruses on the cell surface. Fludase® potentially confers broad-spectrum
protection against all subtypes and strains of influenza viruses (including the
potential pandemic virus H5N1), and without the need for annual updates. It
has built-in features that enable long drug retention on the airway surface, and
is engineered to be nonimmunogenic to humans. It is very stable, and
manufactured cost-effectively through bacterial fermentation and a simple
purification process. Since Fludase® targets a stable and dispensable host
cell component rather than the virus, the likelihood of selecting resistant
strains is greatly diminished. Fludase® has demonstrated broad and potent
anti-influenza efficacy in tissue culture and in two animal models. The CDC
and the NIH have performed tests on Fludase® and both reported the drug
candidate to be highly effective against the clinical isolates of H5N1 viruses.
Additionally, Fludase® has also been shown to effectively inhibit parainfluenza
virus, a virus that causes significant serious respiratory infections and against
which there is currently no vaccine or specific treatment. Fludase® treatment
has been demonstrated to be safe and has a high therapeutic index in animal
studies. In future clinical use it will be delivered to the human airway surface
as an oral inhalant. The treatment effect of a single dose is expected to last
many days; therefore, no more than three treatments are projected for a
clinical therapeutic course.

Viradin(TM) and Inviridin(TM) are also recombinant fusion proteins, and exert
dual antiviral and anti-inflammatory effects. In tissue culture, Viradin and
Inviridin effectively inhibited a broad range of influenza viruses. In addition,
some candidates have also demonstrated inhibitory efficacy against
respiratory syncytial virus (RSV) as well as some paramyxoviruses. Viradin
program has now entered the phase of animal testing.

By having completely novel and different mechanisms of action, Fludase®,
Viradin(TM) and Inviridin(TM) are suited for overlapping, yet distinct clinical
indications. Together, Fludase®, Viradin(TM), and Inviridin(TM) may provide
comprehensive protection against influenza and other serious respiratory viral
infections at various clinical stages.