Acambis starts clinical testing of universal influenza vaccine

Acambis plc (Acambis) (LSE: ACM), a leading vaccines company, announced today that it has initiated a Phase 1 clinical trial of its universal influenza vaccine candidate, ACAM-FLU-A.

ACAM-FLU-A is designed to target all 'A' strains of the influenza virus. As such, it has the potential to be both a universal pandemic influenza vaccine and a part of a universal seasonal vaccine. Historically, influenza pandemics have been caused by 'A' strains of the virus; seasonal vaccines target both 'A' and 'B' strains of the virus.

The Phase 1 trial is:

* A randomised, double-blind, placebo-controlled, multi-centre trial in the US;

* Investigating ACAM-FLU-A's safety, tolerability and ability to generate an immune response;

* Being conducted in up to 80 healthy subjects aged between 18 and 40 years; and

* Assessing two adjuvants or "immune stimulants" to determine whether they improve the effect of the vaccine on the immune system.

ACAM-FLU-A is the first vaccine candidate being developed under Acambis' influenza programme. It is a recombinant vaccine that uses a hepatitis B core protein to present M2e, the extracellular domain of the influenza ion channel protein M2, to the immune system. Being highly conserved, M2e is intended to elicit immune responses to all influenza 'A' strains.

Dr Michael Watson, Acambis' Executive Vice President, Research & Development, commented:

"As a universal vaccine, ACAM-FLU-A can potentially overcome many of the drawbacks of existing influenza vaccines. By removing the need to re-engineer the vaccine each time the virus mutates, a universal vaccine can be manufactured and used at any time of year. It could be stockpiled in advance of a pandemic or potentially used routinely to ensure population protection against future pandemics. This trial is designed to prove that the vaccine generates an immune response as well as giving us safety data. We look forward to seeing the results around the end of this year."

Two adjuvants are being tested in this Phase 1 trial for their effects on the safety and immunogenicity of ACAM-FLU-A: aluminium hydroxide, which is widely used in licensed vaccines; and QS-21 Stimulon(r) adjuvant, which is an investigational adjuvant provided under a licence and option agreement with Antigenics Inc.

ACAM-FLU-A was developed using technology licensed from VIB that was invented by Walter Fiers, Emeritus Professor of the VIB Department for Molecular Biomedical Research at the University of Ghent. Pre-clinical studies of the vaccine in mouse models have shown highly promising results.

Ian Garland, Chief Executive Officer of Acambis, said:

"With the market for influenza vaccines projected to rise to $4bn by 2010(1), this is a very attractive opportunity. Our universal vaccine approach is highly innovative and gives us a strong competitive position in the influenza vaccine market."

Acambis is using multiple approaches to develop innovative influenza vaccines. In addition to ACAM-FLU-A, its programme includes activities to identify a conserved region within the influenza virus 'B' strains, equivalent to M2e in influenza virus A strains. This would enable Acambis to generate a universal vaccine candidate that protects against all B strains, which currently cause the most significant morbidity and mortality in humans.

source;www.pharmalive.com