New Scientific Publication Supports Advantages of Bavarian Nordic’s Poxviral Cancer Immunotherapy Platform
Kvistgård, Denmark, September 15, 2011 - Bavarian Nordic (OMX: BAVA) today announced that a newly published preclinical study investigating the Company's MVA-BN®technology in HER-2 positive tumors, demonstrates the potential advantages of the Company's poxviral cancer immunotherapy technology platform when compared to conventional protein and adjuvant vaccine strategies. The data were published in the current edition of the peer-reviewed journal Cancer Immunology Immunotherapy.
In the paper titled "Immunotherapy with MVA-BN®-HER2 induces HER-2-specific Th1 immunity and alters the intratumoral balance of effector and regulatory T cells," the authors show that a single treatment with MVA-BN®-HER2 exerts potent anti-tumor efficacy in a murine tumor model of experimental lung metastasis. This anti-tumor efficacy occurred despite a strong tumor-mediated immunosuppressive environment characterized by a high frequency of regulatory T cells (Treg) in the lungs of tumor-bearing mice. The data demonstrate that treatment with MVA-BN®-HER2 controls tumor growth through mechanisms including the induction of HER-2-specific immune responses and the control of tumor-mediated immunosuppression. Importantly, similar induction of immunity and tumor efficacy was not observed when immunization strategies were employed that used protein and strong conventional adjuvant.
These data suggest that immunization strategies based on modified vaccinia Ankara (MVA) are superior to protein-based approaches and induce an array immune effects that are generally considered optimal for anti-tumor efficacy. These animal data strongly support the ongoing human clinical trials with the same vaccine and explain the mode of action of potential clinical efficacy of other poxviral cancer vaccines, including the Company's lead product candidate, PROSTVAC®, a cancer immunotherapy product candidate moving into late-stage development for the treatment of patients with metastatic prostate cancer.
An abstract of the article is available on the company's website:
About Poxviruses and Immunotherapy Although increased expression of tumor-associated antigens, such as PSA in prostate cancer, is associated with advanced disease these "self"-antigens do not sufficiently activate the immune system to attack cancer cells. To overcome this poor responsiveness, recombinant poxvirus vectors, including vaccinia, fowlpox and modified vaccinia Ankara (MVA), can be genetically engineered to express one or more tumor-associated antigens along with three co-stimulatory molecules (TRICOM) to greatly enhance the immune system's ability to recognize and destroy cancer cells bearing any of the targeted antigens.