Dr. Michael Har-Noy, CEO of Immunovative Therapies, Ltd. says that the failure of hundreds of immunotherapy clinical studies to produce meaningful anti-tumor treatments calls for a re-evaluation of their underlying theories. For more than 200 years, scientists have successfully used vaccines to prevent many infectious diseases by inducing a humoral antibody response. Dr. Michael Har-Noy notes that researchers have attempted to apply the same ideas in developing vaccines to treat existing cancers, despite the fact that vaccines giving protection against pathogenic infections cannot eradicate existing infections caused by the same pathogen. Therefore, notes Dr. Michael Har-Noy, the modeling of these cancer therapies is fundamentally flawed, because protective immunity does not provide therapeutic immunity.
Dr. Michael Har-Noy indicates that a specific cellular immune response is required to provide therapeutic immunity from cancer. Researchers have followed conventional strategies in cancer vaccine creation by attempting to find unique tumor-specific antigens (TSA) not found on normal cells, or by looking for tumor-associated antigens (TAA) overexpressed by malignant cells. Dr. Michael Har-Noy says that TSAs have only been found in cancers caused by infectious agents, such as EBNA-1 antigen from Epstein Barr virus-induced Burkitt's lymphoma. However, TAAs have been identified in most cancers forming in immunocompetent patients. Furthermore, says Dr. Michael Har-Noy, many malignancies have a significant inflammatory component which includes a widely varied leukocyte infiltrate of neutrophils, macrophages, mast cells, and eosinophils, frequently associated with lymphocytes. Human cancers are usually densely infiltrated with immune cells – a fact arguing against inadequate tumor antigen recognition.
Dr. Michael Har-Noy notes that previous attempts to enhance patients' immune responses have accelerated rather than slowed tumor growth. Therefore, he says, the notion that cancers are “invisible” to the immune system, which thus needs to be augmented, is misconceived. Dr. Michael Har-Noy thinks that the problem is that the patient's immune response to the tumor, while strong, may be the wrong kind. It is therefore not surprising that tumor growth may be enhanced rather than suppressed by attempting to strengthen an immune response that has already failed to protect against cancer growth. Dr. Michael Har-Noy notes that this misconception is the basic flaw in the conventional strategy of cancer vaccine research.
Dr. Michael Har-Noy is conducting a Phase I/II trial of his CRCL vaccine in Bangkok, Thailand. Please visit www.immunocare.net for more information.