TIL therapy and CAR T therapy are both innovative immunotherapies that use a patient’s own T cells to fight cancer, but they differ in important ways in how the cells are obtained, prepared, and used.

 

What is TIL Therapy?

 

Tumor-Infiltrating Lymphocyte (TIL) therapy uses T cells that are naturally found inside a patient’s tumor. These immune cells have already recognized the cancer but are often too few in number to eliminate it.

In TIL therapy, tumor tissue is surgically removed, the T cells are isolated and expanded in a specialized laboratory, and billions of activated T cells are infused back into the patient after a preparative treatment regimen. This approach has shown particular promise in solid tumors such as melanoma.

 

What is CAR T Therapy?

 

Chimeric Antigen Receptor (CAR) T-cell therapy involves collecting T cells from a patient’s blood and genetically engineering them to express synthetic receptors that specifically target cancer cells.

These modified T cells are expanded in the laboratory and then infused back into the patient, where they seek out and destroy cells expressing the targeted antigen. CAR T therapy has demonstrated significant success in certain blood cancers, including leukemia and lymphoma.

 

Key Differences at a Glance

​

• Cell Source: TIL therapy uses T cells extracted from tumor tissue; CAR T therapy uses T cells collected from blood.

• Engineering: TIL cells are not genetically modified; CAR T cells are genetically engineered with synthetic receptors.

• Primary Use: TIL therapy is primarily used for solid tumors like melanoma; CAR T therapy is most established in blood cancers.

• Targeting Mechanism: TIL cells naturally recognize multiple tumor-specific targets; CAR T cells are designed to target a specific antigen.

• Manufacturing Complexity: Both require specialized laboratory production, but CAR T involves gene modification technology.

 

Advantages and Considerations

​

Advantages of TIL Therapy:

​

• Uses naturally tumor-reactive immune cells.

• May recognize multiple tumor antigens, reducing escape mechanisms.

• Particularly promising for solid tumors like melanoma.

• No genetic modification required.

​

Advantages of CAR T Therapy:

​

• Highly specific targeting of cancer cells.

• Strong clinical results in certain blood cancers.

• Engineered for enhanced activation and persistence.

• Established FDA-approved products for specific indications.