Cancer Vaccine Developed by Anosys Demonstrates Positive Results in Melanoma Patients.

Business Editors

MENLO PARK, Calif.--(BUSINESS WIRE)--Oct. 21, 2002

Anosys, Inc. today reported Phase I clinical trial results of Anosys' proprietary cancer vaccine for the treatment of melanoma. In this study, patients with advanced-stage melanoma were treated with Anosys' acellular anticancer dexosomes, delivery vehicles that comprise all the known protein components necessary to activate the major immune responses.

The results show that three of six patients who received an active dose of the vaccine (dexosomes loaded with 100 ug/mL tumor-specific peptide) achieved clinical benefit, either prolonged disease stabilization up to 12 months (2 patients) or tumor shrinkage (1 patient). Importantly a cytotoxic T cell (CTL) response was detected in 5 patients following immunotherapy.

Nancy Valente, M.D., Vice President of Medical Affairs at Anosys commented, "Our Phase I melanoma findings provide the first demonstration of possible patient benefit without the requirement for a high CTL response. We find this particularly encouraging, since we believe this indicates that the quality of the CTL response stimulated by our antigen-loaded dexosomes is sufficient to create a greatly amplified immune response to cancer cells."

Dr. Jean-Bernard Le Pecq, Anosys' Chief Science Officer and Chief Executive Officer, stated, "These encouraging results have given us a clear directive to carry this research forward. Enrollment for a Phase II study comprised of 60 advanced-stage melanoma patients was initiated in July 2002 and is expected to be completed in 2003."

The Phase I melanoma study was conducted at the Institut Gustave-Roussy and Institut Curie in France. The data were presented yesterday at the annual meeting of the European Society of Medical Oncology in Nice, France.

The trial enrolled patients with Stage III and IV melanoma who had failed prior therapy and had previously been treated with up to 4 regimens. In addition, the patients' cancers were positive for the expression of MAGE tumor antigens. Following leukapheresis (removal of a small portion of white blood cells), Anosys manufactured dexosomes, which were loaded with the MAGE-3.A1 and Mage-3.DPO4 tumor peptides, and then administered to the patients by subcutaneous and intradermal injection. Administration of the vaccine was generally well tolerated and there was no evidence of serious toxicity related to the vaccine.

Tumor cells often have unique molecular markers, known as antigens, which distinguish them from other cells. The immune system is able to recognize tumor antigens through the activity of professional antigen presenting cells, called dendritic cells, which capture and process the tumor antigen. Specifically, dendritic cells package tumor antigens in small spherical vesicles known as dexosomes, which themselves activate other immune cells.

Anosys has completed two Phase I studies of patients with advanced cancer. In both trials each patient's dexosomes were isolated from the monocyte-derived dendritic cells and loaded with cancer-specific antigens. Results of a Phase I trial in the U.S. for patients with advanced-stage non-small cell lung cancer were reported at this year's meeting of the American Society for Clinical Oncology (ASCO).

Based on encouraging Phase I results in melanoma, Anosys has initiated a multicenter Phase II study of 60 patients. In addition, Anosys plans to begin a Phase II trial in patients with advanced-stage non-small cell lung cancer in 2003.

Currently, there are approximately 40,000 new cases of melanoma and 180,000 new cases of lung cancer in the U.S. each year. Unfortunately, the incidence of melanoma is increasing, and only five percent of patients with advanced-stage melanoma survive for five years. Eighty percent of patients with non-small cell lung cancer (NSCLC) are diagnosed with advanced disease that is not curable.

Anosys develops innovative therapeutic vaccines for the treatment of cancer, infectious and autoimmune diseases. Anosys' healthcare products are based on a pioneering approach using exosomes, which represent a new paradigm in the understanding of intercellular communication. Exosomes from immune cells are small vesicles that contain all the known components required to activate the major innate and cellular immune responses necessary to fight disease. Exosomes can be genetically engineered to express a variety of proteins on their surface that can be used for multiple purposes, including generation of monoclonal antibodies and specific targeting of proteins to tissues and vaccines. Anosys is currently conducting clinical trials in the United States and Europe to treat multiple forms of cancer, and is advancing additional breakthrough treatments toward clinical testing.