Biovector Therapeutics Acquires 80% Interest in Peptide Immune Ligands.

TOULOUSE, France--(BW HealthWire)--Oct. 21, 1998--BIOVECTOR THERAPEUTICS SA, a privately held company, specializing in drug delivery systems, today announced that it has acquired an 80% stake in Peptide Immune Ligands (PIL), a private French company that specializes in Immunology. PIL develops products to prevent and treat infectious diseases and cancer. PIL focuses on all stages of the immune response (humoral= antibodies ; cellular= T cells), including the molecular and cellular processes.

Under the terms of this agreement, Biovector will retain access to the two founders of PIL, Dr. Helene Gras of the National Center of Scientific Research (CNRS) and Dr. Jean-Gerard Guillet of the National Institute of Health and Medical Research (INSERM), and have them serve as consultants to Biovector. In addition, this agreement will provide Biovector with the ability to enhance its current knowledge of fundamental immunology, improve the design of its drug delivery technologies and gain access to the well-regarded research organizations that collaborate with PIL. Biovector will also support a three-year clinical research program as well as additional research and development projects.

In addition to several pre-clinical programs, PIL currently has two therapeutic vaccine programs about to enter clinical trials, a Phase I trial for HIV and a Phase I/II for malignant melanoma. PIL has also in-licensed patents for the above mentioned indications. These patents were in-licensed from the INSERM, the CNRS and from the Pasteur Institute of Lille (France). In addition to the patent licenses, PIL also has an already established operating network that is in early clinical trials.

The Phase I/II study for malignant melanoma is expected to enroll 14 patients and to begin in 1999. The objective of this study will be to track and destroy the tumour cells. This study will be conducted at an internationally renowned anti-cancer center.

Based on encouraging results from an initial pilot study on HIV, PIL has scheduled an additional Phase I study expected to begin in 1999 and should involve 15 healthy human volunteers. The initial pilot study, conducted at the ANRS, a French National Agency against AIDS, showed encouraging results, including a humoral and cellular mediated immune response. The goal of the additional Phase I study is to test the tolerance and toxicity of the product, as well as evaluating whether an immune response was induced. Dr. Salmon will conduct the study at the Hospital Cochin located in Paris, France. The company's primary objective is to develop a therapeutic vaccine that would reinforce the current tri-therapy treatment. Later on, the Company plans to develop a preventive vaccine for the treatment of HIV.

"This agreement allows us access to a wealth of knowledge and technology and can only enhance and provide additional returns on the current research and clinical programs currently in process here at Biovector," explained Emile Loria, MD, President & CEO of Biovector Therapeutics. "This strategy fits our overall objectives perfectly," Dr. Loria added.

The Lipopeptidic Biovector system will be associated either with specific antigens of malignant melanoma or with selected epitopes of HIV antigens (AIDS application). The Lipopeptidic Biovector system is a new product concept composed of synthetic elements that mimic natural epitopes, which are small pieces of antigens. Proprietary technology allows Biovector to combine lipids with those synthetic epitopes to obtain Lipopeptides. An appropriate selection of those lipopeptides should allow stimulation of all the immune response components against viruses or tumour cell antigens.

Biovector Therapeutics has developed unique and proprietary technologies for delivery of biological products called "biovector systems". These Biovector systems are synthetic particles with unique supramolecular structures that have been designed to improve the efficacy of biotech products. The company is mainly focusing on the treatment of infectious diseases and cancer by a curative or prophylactic immunotherapy approach. Biovector Therapeutics will concentrate its efforts in the development of modern vaccines taking into account all the components for an efficient immune response. In the field of gene therapy, the company will dedicate its efforts in the delivery of DNA encoding for antigenic proteins in vaccine applications and blood circulating proteins in case of deficiency.

PIL, a subsidiary of Biovector Therapeutics, is a biopharmaceutical company that develops products for prevention and treatment of infectious diseases and cancer. The PIL's approach is based on their expertise in the understanding of molecular and cellular processes involved in the control of human immune response. The company focuses on the study of original formulations able to induce and modulate all the components of the immune response (humoral=antibodies ; cellular=T-cells) for an efficient disease control. By acting not only on the causes but also on the evolution of the concerned diseases, PIL's technology is positioned in the therapeutic vaccination area.

Statements made in this release may contain forward-looking statements. Various factors could cause actual results to differ materially from those projected in such statements, including those predicting regulatory processes, the amounts of future payments expected under the collaborative agreement and timing and results of clinical trials. Although the Company believes that the forward-looking statements contained herein are reasonable, it can give no assurance that the Company's expectations are correct. All forward-looking statements are expressly qualified in their entirety by the Cautionary Statement.