TILs are part of the body’s natural response to cancer:
- The cells of the immune system perform immunosurveillance while circulating throughout the body
- As part of the normal immune response, TIL migrate to the tumor site through recognition of chemokines produced by the tumor. TIL recognize tumors through tumor-specific antigens (TSAs) and can cause lysis to tumor cells
- Solid tumors are extremely heterogeneous. Studies suggest that TIL from each individual are unique and polyclonal, which means that TIL may be able to recognize an array of known tumor antigens and unique patient-specific antigens
TILs are Important for helping to eradicate tumor cells. They recognize and eradicate tumor cells in three steps:
- TILs recognize the TSAs on the surface of tumor cells
- TILs can become activated and release perforin, a pore-forming protein
- The newly formed pores allow for the delivery of granzymes, which causes lysis of target cancer cells.
Given the frequently reported inadequacies of conventional cancer therapies and the growing need for personalized medicines, there is a surge in demand for TIL-based therapies. Considering the encouraging clinical trial data and the rising need for safe and efficacious therapies, TIL-based therapies have generated significant enthusiasm among medical R&D professionals in cancer centers around the world. Based on multiple clinical and preclinical stage success stories, TIL-based therapies are anticipated to carve out a significant share of the multi-billion-dollar cancer immunotherapy market.
The benefits of TIL-based therapies, leading to their rapid adoption, are:
- High specificity: Tumor infiltrating lymphocytes recognize and specifically attack tumor cells, enabling TIL therapies to show encouraging success in treating cancer patients with solid tumors, in contrast to genetically engineered T-cell therapy, which have yet to show success in treating solid tumors.
- Excellent safety profile: TIL therapies are shown to be safe without the toxicity issues associated with CAR-T and TCR-T cell therapies. Since TIL therapies are autologous, there is also limited risk of graft versus host disease.
- Lower cost-of-care compared to genetically engineered T-cell therapies: It is estimated that TIL therapies will likely be priced at approximately $200,000 per patient compared to genetically engineered T-cell therapies, which are priced at approximately $400,000 to $500,000 per patient.
- Shorter manufacturing-lead-time translates to faster patient treatment: Manufacturing-lead-time for TIL therapies is approximately four (4) weeks, enabling patients to be treated within 4-5 weeks compared to genetically engineered T-cell therapies, where patient time-to-therapy is often a few months.