PR020 – April 2009

Lipoxen plc and Cambridge Biostability Ltd

Positive Data for Revolutionary Influenza Vaccine

~ Suitability for stockpiling in preparation for H1N1 flu pandemic ~

Lipoxen plc (AIM:LPX) (“Lipoxen” or “the Company”), a bio-pharmaceutical company specialising in the development of high value differentiated biologicals, vaccines and siRNA delivery, and Cambridge Biostability Ltd (CBL), the developer of temperature stable vaccines and biopharmaceuticals, are pleased to announce that they have achieved positive preclinical results for the delivery of a novel and enhanced influenza vaccine based on the combination of Lipoxen’s novel vaccine delivery system ‘ImuXen’ and CBL’s proprietary VitRIS stabilisation platform.

The study results show that ImuXen increases the effectiveness of influenza vaccine materials by approximately 30-fold. In addition, the VitRIS formulation enhances the efficacy of the vaccine a further 4-fold. As a combined product, the VitRIS-preserved ImuXen formulation has the potential to achieve a projected 10-fold advantage in vaccine production rates, addressing the greatest potential need for seasonal and pandemic influenza vaccines for existing and newly emerged flu viruses.

Highlights of the results:

ImuXen shown to increase the effectiveness of influenza vaccines by approximately 30-fold
VitRIS formulation enhances the efficacy of the vaccine by a further 4-fold
Potential to radically increase output of vaccine doses from existing manufacturing facilities - projected 10-fold advantage in vaccine production rates
No requirement for 'cold-chain' of refrigerated trucks, warehouses and fridges

The study, which was undertaken by Lipoxen and CBL with analysis of blood samples conducted by Retroscreen Virology Ltd in London, was set up to determine the capability of Lipoxen’s ImuXen technology, in combination with CBL’s VitRIS stabilisation technology, to create a stable vaccine formulation that would increase antibody production against an H1N1 Influenza virus which was supplied by the UK National Institute for Biological Standards and Control (NIBSC), the Government body responsible for safeguarding and advancing public health by assuring the quality and safety of biologicals. Data from the study was independently reviewed by Professor Will Irving, a Consultant Virologist at Nottingham University's Queen’s Medical Centre and a leading UK virologist who has worked on influenza for over 15 years.

Lipoxen, in association with CBL and with funding from the Technology Strategy Board (formerly the DTI), have created a novel water-free influenza vaccine formulation, that will be heat and freeze stable and will not require refrigeration during transport, storage and distribution.

Lipoxen’s ImuXen technology entraps regular flu vaccine material (killed virus particles) into the Company’s proprietary liposomes to provide an enhanced antibody response compared to a regular vaccine formulation. CBL’s VitRIS technology enables the liposomes to be dried and stabilised within microscopic particles of sugar glass which can then be suspended in a user-friendly biocompatible oil. The thermostable liquid vaccine is then ready for immediate injection and has the added advantage that it can be used for long term stockpiling.

The results of the study give clear indication that Lipoxen’s vaccine technology coupled with CBL’s formulation techniques, not only provide a significantly enhanced vaccine response but also a dramatic advantage in increased vaccine production rates. This advantage addresses the greatest need of seasonal and pandemic influenza vaccines based on newly emerged flu viruses, such as the recent swine flu outbreak.

Following the study results, Lipoxen have selected a lead vaccine candidate and are currently conducting stability studies at elevated temperature in partnership with CBL.

Lipoxen and CBL are also in discussion with major vaccine manufacturers with a view to licensing the new technology package for pandemic and seasonal influenza vaccines.

Commenting on the announcement, M. Scott Maguire, CEO of Lipoxen, said:

“This new very positive data on a novel flu vaccine candidate comes at a critical time for the World particularly in light of the current potential for a swine flu outbreak where the death toll is climbing daily and the spread of disease is an enormous current global threat. These results show that we have the technology to develop a novel flu vaccine candidate suitable for pandemic planning. Our vaccine candidate offers the advantages of enhanced immune response, fast and high volume production as well as no requirement for a cold-chain, all ideal characteristics in planning for further pandemic situations. Based on the results we are encouraged to believe that it would also work for the new swine flu 2009 strain since an earlier human derived H1N1 strain was used in the studies reported today. We look forward to working with CBL to maximise the commercial potential of this flu vaccine candidate.”

Also commenting on this announcement, Dr David Moss, Director of Research at Cambridge Biostability, said:

“We are delighted that our VitRIS technology has allowed the development of a thermo-stable, instantly injectable vaccine against influenza. Thermostability, the removal of reliance upon the cold chain, coupled with the fact that the vaccine needs no reconstitution prior to injection are two major steps forward in the development of the next generation of vaccines and other biologics aimed at both the developing and developed world markets.”

Adding to this, Professor of Virology Will Irving, an independent Consultant Virologist at Nottingham University's Queens Medical Centre, said:

“This new influenza vaccine formulation has generated some very exciting data. The potential to generate protective antibody responses whilst using surprisingly low doses of antigen is a major potential breakthrough - in the H5N1 vaccine field, published data suggest that prohibitively large doses of antigen may be needed in order to generate protective responses. The novel delivery vehicle, showing stability at ambient temperatures, will also be a huge benefit, allowing delivery of vaccine in situations which otherwise would experience great difficulties in achieving successful transport and storage of traditional vaccine preparations.”

For further information:

Lipoxen plc +44 (0)20 7691 3583
M. Scott Maguire, Chief Executive Officer

Cambridge Biostability Ltd +44 (0)1223 437400
Kiran Gulati, Director of Business Development

Singer Capital Markets (nominated adviser) +44 (0)20 3205 7500
Jeff Keating / Claes Spång

Noble & Company +44 (0) 20 7763 2200
John Llewellyn-Lloyd / Sam Reynolds

Buchanan Communications +44 (0)20 7466 5000
Mary-Jane Elliott, Lisa Baderoon, Rebecca Skye Dietrich, Catherine Breen

 

Notes to Editors
About Influenza and reasons for the study
Influenza has been established as a serious human affliction that can cause localised epidemics and global pandemics of acute respiratory infections. Each year the Influenza virus is responsible for 20,000 to 40,000 deaths and up to 300,000 hospitalisation cases in the United States (Sandhu & Mossad, 2001). In the pandemic of 1918 it is widely believed that in excess of 40 million people died.

Although children and younger adults experience more cases of infection, severe illness is more common in the elderly, immunocompromised individuals, or those with chronic illnesses such as asthma, diabetes, kidney failure and heart disease. (Stamboulian et al., 2000).

The annual epidemics run from November to March in the Northern Hemisphere, and from April to September in the Southern Hemisphere (Cox & Subbarao, 2000). The impacts of these viruses have led to the search for alternative compounds with which to minimize their effects within human populations.

Immunisation, with current inactivated vaccines given parentally, is effective at reducing mortality, attenuating the symptoms of the disease, and minimising the sequelae associated with Influenza. It has also been proposed that immunisation of young children, identified as enhancing ongoing viral transmission in communities (Reichert, 2002; Reichert et al., 2001), might significantly reduce the spread of Influenza virus in the community. Therefore, the development of an efficacious highly
tolerable vaccine, suitable for all members of a community would be of great benefit.

The majority of current vaccines have several limitations, including non-biodegradability, a depot effect, inflammation and induration at the site of injection, and either a weak, or no, cellular immune response. Attempts to increase antibody response by increasing the antigen content per dose have not always resulted in improved immunogenicity (Couch et al., 1997).

About Lipoxen
Lipoxen plc (AIM: LPX) is a biopharmaceutical company specializing in the development of high value differentiated biologicals, vaccines and siRNA delivery. Products currently under development include improved formulations of important biologicals such as erythropoietin (EPO), G-CSF, insulin and Interferon-alpha. Lipoxen has two products in clinical development SuliXen, a long acting insulin and long-acting EPO. These novel products, which are based on Lipoxen’s proprietary PolyXen® technology, each address markets in excess of US$1 billion.

Lipoxen’s technology is designed to improve the stability, biological half-life and immunologic characteristics of therapeutic proteins naturally. Lipoxen has two further naturally-derived proprietary delivery technologies, ImuXen® and a related liposomal technology to enhance the efficacy and safety of various vaccines such as a multivalent Hepatitis B-E, HIV and pneumococcal vaccines. The Company has a third technology, siRNAblate for the delivery of siRNA. The Company’s proprietary delivery technologies are attracting significant interest from the world’s largest biopharma companies and Lipoxen is currently co-developing products with the Serum Institute of India Limited (one of the world’s leading vaccine companies, India’s largest biotech company and a major shareholder in Lipoxen) and has license agreements in place with Baxter International and Schering-Plough and a grant for development of a novel HIV vaccine candidate from International AIDS Vaccine Initiative (IAVI), the world’s leading AIDS vaccine organization.

Lipoxen was admitted to trading on the AIM Market of the London Stock Exchange in January 2006.

For more information please visit www.lipoxen.com.