BioWorld International Correspondent

LONDON - A UK start-up has reached proof of concept in an animal model for a flu vaccine that would provide year-round protection regardless of mutations in the virus, and would be effective against animal flu viruses such as the avian H5N1 strain also.

The vaccine, based on six peptides, can be manufactured by semi-synthetic routes avoiding the need for the time-consuming process of producing vaccine in chicken eggs.

The product, FLU-v, is based on six highly conserved epitopes that are common to all recorded human and animal flu viruses over the past 60 years. The six were selected from the field of conserved epitopes because they are known to elicit a cytotoxic T-cell response. The company behind the development, PepTcell Ltd., claims FLU-v will be effective against all strains of the virus, including pandemic strains.

The High Wycombe-based company honed in on those epitopes using proprietary algorithms. While there is a range of techniques for singling out conserved epitopes, PepTcell claims none are as fast and effective, or have the ability to single out epitopes that will elicit a cytotoxic T cell response.

"A number of elements came together to enable us to achieve this," Stuart Robinson, head of business development told BioWorld International. "There is an explosion of knowledge and understanding in immunology, with a huge amount of new data being added."

"This comes together with [the company's] novel insights as to how antigens bind to cytotoxic T cells," he said.

The preclinical data, presented this week at the 2007 Options for Control of Influenza conference in Toronto, showed transgenic mice vaccinated with FLU-v had a significantly increased survival rate when challenged with a lethal dose of virus, compared to mice given a control vaccine.

In another experiment, the spleen was removed and tested against a range of different flu viruses. "They were all constrained," Robinson said.

PepTcell is due to talk to the UK regulator to discuss the design of a Phase I trial and aims to start it in 2008. Work to scale up manufacturing is under way.

The algorithm potentially can be applied to all rapidly mutating viruses to find immunogenic regions that are conserved. PepTcell's second project is in HIV, where Robinson said the company now has experimental data to support the formulation of a vaccine.

The concept is relevant to autoimmune diseases such as Crohn's disease and rheumatoid arthritis also, and Robinson said PepTcell has done some early stage work.

The company, founded in 2004, is funded by high net worth individuals and has not disclosed how much money it has raised to date.

Robinson said there is sufficient cash to progress FLU-v to Phase II. PepTcell wants to find a partner for Phase III and commercialization, but is prepared to do a deal sooner to get access to strategic advice on the earlier development pathway.