A patient with advanced lung cancer, after nine months of treatment, has used almost all chemotherapy regimens, PD1 inhibitors have also been used, but the condition is still progressing, and plans to come to Shanghai to enroll in a clinical trial, this clinical trial is TILs treatment. Unfortunately, because of the epidemic situation, I can't come to Shanghai, the condition is not waiting for anyone, and it is estimated that there will be no chance in the future, and I can only sigh.
What are TILs treatments?
TIL is an abbreviation of tumor infiltrating lymphocytes, strictly speaking, heterogeneous lymphocytes in the tumor interstitium, including T cells and NK cells. In 1986, immune titan Rosenberg and his team first found in the tumor tissue surgically cut by a patient with advanced melanoma that in addition to a large number of tumor cells, there were a small number of lymphocytes.
You may not know that there is anti-tumor immunity in everyone's body. When the body's immune system finds cancer cells in the body, it will mobilize the immune army to go deep into the tumor tissue to recognize, resist and attack the cancer cells, and the lymphocytes that go deep into the cancer tissue are TIL. Therefore, tumor tissue and the surrounding part of T cells are the most powerful immune cells that recognize and kill tumor cells. They release cytotoxins to kill cancer cells directly and regulate the body's immune function.
However, the number of TIL in tumor tissue is very small, coupled with the inhibition of PD-1, the influence of the immune microenvironment, the role of these lymphocytes is greatly inhibited, it can be said that "there is heart weakness", resulting in an extremely weak anti-tumor immune effect. So the researchers extracted this small fraction of the extremely valuable cells, expanded them in large quantities in vitro, and then transfused back into the patient. In this way, whether it is the number or the ability to attack, TIL has obtained "amplification", thus playing a role in killing cancer cells.
It can be seen that TILs are a new type of cell-based immunotherapy. This means that we can use our own immune cells to kill tumors, which is a safer immunotherapy.
How effective are TILs? Is it effective for lung cancer?
Melinda Baccini was the first super survivor in the world to receive TILs cell immunotherapy, and having been diagnosed with advanced cholangiocarcinoma, she has successfully crossed the decade from a mother of six children to a grandmother, and went to the White House as the American Cancer Moonshot Moon Landing Program to compete in competitions to tell her personal story.
Data from a clinical trial of melanoma showed that remission rates ranged from 49% to 72% in patients with metastatic melanoma, with more than 20% of patients using the therapy to survive long-term. 20 patients achieved complete remission (CR). Among these fully responders, the 3-year survival rate was 100% and the 5-year survival rate was 93%. It is worth mentioning that patients with PD-L1 negative also responded, which indicates that patients who do not respond to immune checkpoint inhibitors can still benefit from TIL therapy.
In terms of lung cancer, a phase I clinical result was announced: in 12 patients with non-small cell lung cancer who could be evaluated, TIL therapy achieved an overall response rate of 25%, of which 2 patients achieved a lasting complete response.
TiLs therapy in the United States has been awarded the title of breakthrough therapy by the FDA in two major cancers, melanoma and cervical cancer. Based on previous research results, TILs are considered to be a adoptive immunotherapy that is superior to CAR-T. If it is listed in the future, it will be called a "new weapon" for solid tumor treatment.