Our targeted cancer immunotherapy approach is currently based upon two key areas: preventing secondary recurrence of cancer, which is becoming increasingly important as the number of cancer survivors continues to grow; and, transitioning earlier in the breast cancer treatment spectrum via primary prevention. Once a patient’s tumor becomes metastatic, the outcome is most often fatal, making the prevention of recurrence a potentially critical component of overall patient care. Our programs primarily target patients in the adjuvant (after-surgery) setting who have relatively healthy immune systems, but may still have minimal residual disease. Minimal residual disease, or single cancer cells (occult cancer cells) or micrometastasis, are undetectable by current radiographic scanning technologies, but we know can result in disease recurrence.
Our therapies utilize an immunodominant peptide combined with the immune adjuvant, recombinant human granulocyte macrophage-colony stimulating factor (rhGM-CSF), and work by harnessing the patient’s own immune system to seek out and attack any residual cancer cells. Using peptide immunogens has many potential clinical advantages, including a favorable safety profile, since these drugs may lack the toxicities typical of most cancer therapies. They also have the potential to evoke long-lasting protection through activation of the immune system and a convenient, intradermal mode of delivery.
NeuVax™ (nelipepimut-S) is a cancer immunotherapy targeting human epidermal growth factor receptor (HER2) expressing cancers. NeuVax is the immunodominant nonapeptide derived from the extracellular domain of the HER2 protein, a well-established and validated target for therapeutic intervention in breast and gastric carcinomas. The NeuVax vaccine is combined with GM-CSF for injection under the skin, or intradermal administration. Data has shown that an increased presence of circulating tumor cells (CTCs) may predict Disease Free Survival (DFS) and Overall Survival (OS)-suggesting a dormancy of isolated micrometastases, which, over time, may lead to recurrence. After binding to specific HLA molecules on antigen presenting cells, the nelipepimut-S sequence stimulates specific cytotoxic T lymphocyte (CTLs). These activated CTLs recognize, neutralize and destroy, through cell lysis, HER2 expressing cancer cells, including occult cancer cells and micrometastatic foci. The nelipepimut immune response can also generate CTLs to other immunogenic peptides through inter- and intra-antigenic epitope spreading.
*NeuVax™ is an investigational product. Efficacy has not been established. Herceptin® is a registered trademark of Genentech.