BioWorld International Correspondent

PARIS - Immutep SA completed a first-round private financing in which it raised €2.5 million.

The investors were five French venture capital funds - FCPI Poste Innovation 1, 2 and 3, which are funded by the French Post Office group, and Innoven FCPI 5 and 6, of the Paris-based firm Innoven Partnenaires. Innoven manages the Post Office funds, as well as its own.

Immutep, which was founded in 2001 and is based in Orsay, southwest of Paris, said the funding was completed last December and that it is continuing to negotiate with other investors to raise additional financing. John Hawken, the company's co-founder and CEO, told BioWorld International he is negotiating to raise an additional €6 million. Hawken added that a total of €8.5 million would be sufficient to last Immutep to the end of 2006.

It already has received grants from the University of Paris, the French Ministry of Research and France's National Research Promotion Agency (Anvar), from which Hawken said Immutep hoped to obtain a "substantial grant" this year.

The company plans to use the funds to move its lead compound, IMP321, through preclinical and early stage clinical development. IMP321 is a natural human T-cell immunostimulatory factor designed to amplify the T-cell immune response. It is being developed for the treatment of hepatitis B and other infectious diseases and allergies. Immutep's pipeline also includes vaccine candidates for three types of cancer (prostate, colon and cervical), as well as for HIV, allergy and asthma.

IMP321 is based on the natural human protein LAG-3, which was discovered by the company's other co-founder, Frédéric Triebel, a professor at the University of Paris. LAG-3 acts as a stimulant of antigen-presenting cells, in particular dendritic cells. In combination with the appropriate antigen, it is designed to act as a natural immunostimulant in therapeutic vaccination, increasing the T-cell immune response.

That technology was partly developed by Serono SA, of Geneva, which has granted the firm an exclusive worldwide license for the use and sale of LAG-3-related products and applications. Immutep plans to develop therapeutic vaccines both in-house and in collaboration with others, and says it is negotiating with others.

Immutep's technology makes it possible to use therapeutic vaccination for treating diseases in which the only effective immune response comes from T cells. Proof of concept already has been established in animal models of three types of tumors, as well as in infectious diseases such as HIV and hepatitis B virus. The company is applying the same therapeutic approach to the treatment of allergies and asthma.

Hawken said a Phase I trial of IMP321 alone - not loaded with any antigen - would begin next April, after which benchmarking trials would be carried out with the hepatitis B surface antigen (HBsAg) and the influenza split-virus antigens. The combination of IMP321 and HBsAg has been validated in preclinical mouse studies. Influenza split-virus vaccine also is a clinically approved vaccine antigen. Immutep says there is an unmet medical need for developing adjuvant influenza vaccines that induce T-cell responses and provide better protection for young infants and the elderly.

But Hawken stressed that the proof-of-principle projects probably would not be taken into a therapeutic phase. The first therapeutic trial of IMP321 would be for prostate cancer and would get under way early in 2006, Hawken said.

The company says cervical carcinoma is a good model for testing cancer immunotherapies because it is a human cancer in which tumors are associated with a virus - the human papillomavirus (HPV) in more than 90 percent of cases. Immutep is targeting its therapeutic approach at the HPV16-encoded E7 oncoprotein, which is expressed in cervical carcinoma cells and is required for cellular transformation to be maintained. The E7 protein thus forms an attractive target for T-cell-mediated immune intervention to prevent or treat HPV16+ tumors.

Immutep said therapeutic strategies combining specific anti-HIV immunotherapeutics with antiretroviral drugs have demonstrated their capacity to induce high levels of HIV-specific CD8 cytotoxic T lymphocytes, together with a strong CD4 T-cell help response. The company said associating LAG-3 with the HIV antigens in those immunotherapeutics would enhance the induction or restoration of HIV-specific CD4 and CD8 T-cell responses from HIV-infected patients with a sub-normal immune status who already are being treated with antiretroviral drugs.