US patent for NexBio sialic acid targeting flu drug tech
Vaccines such as Sanofi Pasteur's Fluzone and neuraminidase inhibitors like Roche’s Tamiflu and GlaxoSmithKline’s (GSK) Relenza aim to prevent influenza infection by targeting the virus directly via specific molecular interactions.
This approach, while effective, is prone to the development of resistant strains as mutations during viral replication will inevitably produce viruses that such therapeutic agents cannot attach to, which are known as “escape mutants”.
In contrast, NexBio's technology blocks infection and development of resistant strains by cleaving the invariant sialic acid molecules on epithelial cells in the respiratory tract that the virus would otherwise use as a point of attachment and entry.
NexBio spokesman Mike Havluciyan told in-PharmaTechnologist that the main drivers for the development of the technology, and lead drug candidate Fludase, were “safety, potentially increased efficacy and reduced resistant mutants.”
“Our pre-clinical data shows that Fludase is effective against all forms of influenza on which it was tested, including the current H1N1 and strains of influenza that are resistant to neuriminidase inhibitors like Tamiflu.
He went on to say that: “The advantage of Fludase over vaccines is obvious given that vaccines must be developed anew each year based on the prevailing strain from that year.”
Havluciyan explained that because Fludase is administered via inhalation its action is limited mainly to cells of the upper respiratory tract to which the influenza virus would otherwise bind.
He also said that: “The drug acts only for the duration of time that is needed to fight the virus attempting to invade the body,” and that no serious adverse events resulting from Fludase’s interaction with the sialic acid residues emerged during phase I trials.
Havluciyan also said that Fludase, currently in Phase II development, and the targeting technology on which it is based has attracted a great deal of interest from pharma companies but did not go into details for reasons of confidentiality.
