ImPACT Therapy – A First-In-Class Fully Human Cytotoxic T Cell Specific Immunotherapy

Heat Biologics’ proprietary off-the-shelf Immune Pan-Antigen Cytotoxic Therapy (“ImPACT” Therapy) is an engineered cell line designed to express a version of a naturally occurring heat-shock protein known as gp96.  Our ImPACT technology transforms allogenic living cancer cells into powerful miniature osmotic pumps that continually secrete heat shock protein gp96, the most potent mammalian adjuvant ever described, along with its chaperoned antigens.

Heat’s ImPACT technology is able to simulate a process that our immune systems have naturally evolved over millions of years to detect. gp96 is a “molecular warning system” that has evolved important properties as a natural defense against necrotic cell death, in order to serve as a sentinel to alert our immune systems to the presence and identity of dangerous pathogens. Thus, by developing cell lines to secrete an engineered form of gp96, Heat’s ImPACT technology is able to simulate a process that our immune systems have naturally evolved over millions of years to detect.

In contrast to other vaccine technologies, Heat’s approach has been shown to the body to induce and maintain an immune response against multiple tumor proteins, thus unleashing a powerful multi-prong attack against the tumor. Clinical and pre-clinical results indicate that the ImPACT Therapy generates a potent anti-tumor immune response that fights targeted tumors and keeps the body tumor-free even when re-challenged with the cancer. This novel live cell vaccine approach is applicable to a wide array of viral infections (including HIV and HCV), parasitic infections (including malaria) and cancer.  Heat’s approach is an off-the-shelf product that does not require invasive surgery or isolation of patient tissues which is required for autologous vaccine technologies.

ImPACT Immunotherapy Advantages:

  • ImPACT represents a first-in-class adjuvant that functions as both an immune activator and an antigen-delivery vehicle.
  • In addition, ImPACT is the only adjuvant currently in clinical development that is specific to CD8+ cytotoxic T cell immune responses, which is especially important for developing therapeutics in oncology and a number of infectious disease indications.
  • Where traditional adjuvants including aluminum salts and MPL require microgram quantities of individual antigens, ImPACT adjuvants stimulate immune responses against the full antigenic fingerprint of cells at picomolor quantities of individual antigens – which represent physiological concentrations of antigen.

The CD8+ cytotoxic T cell specific nature of the ImPACT system predicts that it will be most useful in stimulating immune responses for diseases where actual cell-killing is an important part of the therapeutic effect. Cancer, which is a disease of mutated cells, naturally became the first indication. ImPACT applied to cancer therapy contrasts in several critical ways to other cancer immunotherapy technologies:

  • ImPACT is an off-the-shelf approach which does not require any surgery or material from the patient and has no storage or production limitations,
  • ImPACT therapy stimulates an immune response against the full antigenic repertoire of the cancer cells, not just one or a handful of antigens
  • ImPACT therapy is specific to CD8+ T cells and does so at physiologic concentrations of antigen. No other approach has these qualities.

Clinical Development

Heat is advancing an aggressive Development Pipeline to target its ImPACT Therapy against a range of diseases. Currently, Heat is conducting multiple clinical trials in two indications with its ImPACT therapy based products, HS-410 to treat Non-Muscle Invasive Bladder Cancer (NMIBC) and HS-110 to treat Non-Small Cell Lung Cancer (NSCLC).