BioWorld International Correspondent

PARIS - Vaxon-Biotech and the Institut Pasteur entered a cross-licensing and collaboration agreement to develop and commercialize new vaccine products and novel transgenic animal models.

The deal calls for Vaxon-Biotech's therapeutic vaccines for cancer to be validated using newly developed transgenic mice humanized by the Institut Pasteur's Laboratory of Cellular Immunity through the human leukocyte antigen (HLA). With the collaboration, Vaxon-Biotech aims to develop a pipeline of products covering major HLA super-families to treat most types of cancer.

Financial terms were not disclosed.

Paris-based Institut Pasteur's expertise in immunology is focused in particular on viral pathologies (including HIV) and cancer, while Vaxon-Biotech, which was founded in 2004 and operates out of the Genopole biotechnology science and business park in Evry, France, is pioneering the development of vaccines based on a new class of antigens - optimized cryptic peptides.

Its most advanced products, Vx-001 and Vx-006, both are designed to treat solid tumors, but are restricted to HLA-A2 patients. Vx-001, which was tested in a Phase I trial last year, contains hTERT572Y, a single, optimized cryptic peptide that targets tumors expressing the telomerase antigen, which is overexpressed in many cancers, including colon, breast, prostate and lung.

The trial demonstrated that the product stimulated T-cell immunity and afforded continuing clinical benefit to patients. The trial was carried out on patients suffering from different types of advanced metastatic cancer that had progressed despite chemotherapy.

Two Phase II trials now are planned for Vx-001 starting this year. One will be a pivotal Phase IIb trial in the indication of hepatocellular cancer, which will be conducted in centers on both sides of the Atlantic, while the other will be a Phase IIa trial in non-small-cell lung cancer. That trial will be carried out in France, Italy and Greece.

As for Vx-006, it is nearing the end of regulatory preclinical studies and is due to be tested in a Phase I/II trial in prostate cancer in France starting in mid-2006.

Vaxon-Biotech's CEO, Philippe Berthon, told BioWorld International that the company had two other products in preclinical development, but they also were for the treatment of solid tumors and were restricted to HLA-A2 patients. He explained that the collaboration with Pasteur would "generate a new class of vaccines" that would not have the same limitations as the company's existing products and would be applicable to a wider range of cancers as well as to infectious diseases.

He expects the collaboration to generate one or more products ready for taking into regulatory preclinical development by autumn.

Berthon said Vaxon-Biotech needs access to mouse models that replicate both human tumors and human immune responses.

The Institut Pasteur is well equipped to cater to that need since, as the head of its cellular immunity laboratory, François Lemonnier, pointed out, it has been developing animal models that faithfully replicate human immune responses ever since the first human histocompatibility HLA class I genes were isolated 20 years ago.

He explained that the animals were suitable for the preclinical design and evaluation of candidate vaccines against human viral infections and cancers, and that Pasteur already had succeeded in using such mice to identify and optimize new molecules that specifically were expressed by tumor cells and thus were safe targets for immunotherapy.

The founder and chief scientific officer of Vaxon-Biotech, Kostas Kosmatopoulos, has been collaborating with the Institut Pasteur for many years, which was why the company was able to take its lead compound into clinical development within a year of its founding.