PANVAC™-VF: poxviral-based vaccine therapy targeting CEA and MUC1 in carcinoma

Abstract

PANVAC™ is a cancer vaccine therapy delivered through two viral vectors – recombinant vaccinia and recombinant fowlpox – which are given sequentially. Both vectors contain transgenes for the tumor-associated antigens epithelial mucin 1 and carcinoembryonic antigen, which are altered or overexpressed in most carcinomas. The vectors also contain transgenes for three human T cell costimulatory molecules required to enhance immune response: B7.1, intracellular adhesion molecule-1 and leukocyte function-associated antigen-3. PANVAC is injected subcutaneously and processed by the body’s antigen-presenting cells. Preclinical studies have demonstrated the efficacy of PANVAC in inducing both carcinoembryonic antigen- and mucin 1-specific cytotoxic T lymphocyte responses in vitro and in murine models. Other strategies that enhance the immune response include the use of granulocyte-macrophage colony-stimulating factor and a prime–boost administration sequence. Clinical trials have demonstrated PANVAC’s safety and its ability to induce antigen-specific T cell responses. Early clinical trials are evaluating PANVAC alone and in combination with conventional chemotherapy and/or radiation. Studies to date hold promise for the use of PANVAC as a means to stimulate the immune system against malignancies and to provide clinical benefit.

Keywords::

• cancer vaccine
• carcinoembryonic antigen
• carcinoma
• CEA
• epithelial mucin 1
• MUC1
• TRICOM

Acknowledgements

This research was supported by the Intramural Research Program of the NIH, NCI, Center for Cancer Research. The authors gratefully acknowledge the thoughtful review and discussion of this manuscript by J Schlom PhD, and the expert editorial assistance of BL Casey in its preparation.