Approved: CAR-T (US, Japan, Europe), TIL and TCR-T (US) CAR-NK: clinical trial stage — studies in patients are ongoing
The main types of immune cell therapy for cancer are CAR-T, TIL (tumor-infiltrating lymphocytes), TCR-T and NK cell therapy. Each one grows or modifies immune cells outside the body and then infuses them back. CAR-T is an approved treatment for blood cancers in the US and Japan, and in 2024 TIL and TCR-T became the first cell therapies approved in the US for solid tumors such as melanoma and synovial sarcoma. This article compares how the four work, which cancers they treat, results in patients and the treatment process, based on overseas primary sources.
What is immune cell therapy? Strengthening immune cells and giving them back
Immune cell therapy is also called adoptive cell therapy. Our T cells and NK cells can attack cancer cells, but as a tumor grows these cells may become too few or lose strength. Doctors therefore collect immune cells from the blood or from tumor tissue, expand them in the lab or add genes that help them find cancer, and then return them through a vein.
The Cancer Research Institute groups these treatments into TIL, TCR-T, CAR-T and NK cell therapy, according to where the cells come from and how they recognize cancer. The names sound alike, but the target cancers and approval stages differ.
The four types of immune cell therapy at a glance
| Type | Cells used | How it finds cancer | Main cancers | Approval status |
|---|---|---|---|---|
| CAR-T | T cells from the patient’s blood | An engineered receptor (CAR) grabs a marker on the cancer cell surface | Lymphoma, leukemia, multiple myeloma | First US approval 2017; approved and insured in Japan since 2019 |
| TIL | T cells inside the tumor | Expands T cells that already recognize that cancer | Melanoma | US accelerated approval, February 2024 (Amtagvi) |
| TCR-T | T cells from the patient’s blood | A new T cell receptor also recognizes fragments of proteins from inside cancer cells | Synovial sarcoma | US accelerated approval, August 2024 (Tecelra) |
| NK cells and CAR-NK | The patient’s own NK cells or cord blood NK cells | Recognize abnormal cells on their own (CAR-NK adds a CAR) | Blood cancer trials; in Japan, self-pay care for various cancers | Self-pay care under Japan’s Regenerative Medicine Act; CAR-NK in clinical trials |
Sources: Cancer Research Institute, reports of US FDA approvals (AACR, CURE), reports of Japan’s insurance listing. Accelerated approval is maintained depending on confirmatory trial results.
CAR-T: the cell therapy shown to extend survival in blood cancers
CAR-T is made by adding an engineered receptor called a CAR (chimeric antigen receptor) to the patient’s T cells. The CAR binds directly to markers on the cancer cell surface such as CD19 or BCMA, so it works regardless of the patient’s tissue type (HLA). Since the first US approval in 2017, several products, including Yescarta, Kymriah and Carvykti, have been used for lymphoma, leukemia and multiple myeloma.
In the phase 3 ZUMA-7 trial of 359 patients with large B-cell lymphoma that relapsed after first treatment, the 4-year overall survival rate with CAR-T (axicabtagene ciloleucel) was 54.6%, compared with 46.0% with standard care, a 27% lower risk of death. In Japan, Kymriah was first approved in March 2019 and insurance coverage was decided the same year (price at listing about 33.5 million yen).
Side effects to watch for are cytokine release syndrome, which causes high fever and low blood pressure, and neurological toxicity. Approved hospitals have the medicines and close-monitoring systems to manage them.
TIL: expanding the T cells that were already fighting inside the tumor
TILs (tumor-infiltrating lymphocytes) are T cells that have already entered the tumor tissue. Because they have already recognized that patient’s cancer, they are expanded in large numbers and returned without genetic modification. On February 16, 2024, the US FDA granted accelerated approval to lifileucel (Amtagvi), the first TIL therapy for a solid tumor.
It is for adults with unresectable or metastatic melanoma previously treated with a PD-1 inhibitor and, if eligible, a BRAF inhibitor. In the phase 2 trial, tumors shrank in 31.5% of the 73 patients who received the recommended dose. The median duration of response had not been reached at the time of analysis, showing that responses were lasting. Patients receive chemotherapy to reduce lymphocytes before the infusion and interleukin-2 afterward to help the cells grow, so treatment takes place in hospital.
TCR-T: a T cell therapy that finds targets from inside the cell
TCR-T is made by adding a new T cell receptor (TCR) to T cells. A CAR only sees the cancer cell surface, while a TCR also recognizes fragments of internal proteins that cancer cells display on their surface. This opened a path for solid tumors that lack a suitable surface marker. The patient’s tissue type (HLA) must match, so a blood test comes first.
In August 2024, the US FDA granted accelerated approval to afamitresgene autoleucel (Tecelra) for unresectable or metastatic synovial sarcoma previously treated with chemotherapy. It is for patients with an HLA-A*02 tissue type whose tumors express the MAGE-A4 protein. In the SPEARHEAD-1 trial, tumors shrank in 43% of 44 patients and 4.5% had a complete response. Among responders, 39% had a response lasting 12 months or longer.
NK cell therapy and CAR-NK: treatments with a lighter side-effect burden
NK (natural killer) cells recognize and attack abnormal cells without prior training. In Japan, therapy that expands a patient’s own NK cells and returns them is offered as self-pay care by facilities that have filed a plan under the Regenerative Medicine Act. The schedule from blood draw to infusion is explained in NK cell therapy process.
CAR-NK, which adds a CAR to NK cells, also has results in patients. At MD Anderson Cancer Center in the US, cord blood-derived CAR-NK cells were given to 11 patients with relapsed or refractory lymphoma or chronic lymphocytic leukemia. Eight (73%) responded and seven reached complete remission. There were no cases of cytokine release syndrome, neurotoxicity or graft-versus-host disease. Because it can be made in advance from donor cells, CAR-NK is drawing attention as a way to shorten waiting times, and clinical trials continue in many countries. For a detailed comparison with CAR-T, see CAR-NK vs CAR-T.
How does the treatment process differ?
CAR-T and TCR-T start by collecting T cells through apheresis. TIL starts with surgery to remove part of the tumor. Making the cells takes several weeks, and treatment to control the disease may continue in the meantime. For all three, patients receive lymphocyte-reducing chemotherapy a few days before a single infusion and are then monitored in hospital. Autologous NK cell therapy in Japan starts with an ordinary blood draw and is given in several outpatient infusions, so the physical burden is relatively light.
Questions for your doctor
- Given my cancer type and past treatment, am I eligible for an approved cell therapy?
- If I need CD19 or BCMA marker tests, or HLA and MAGE-A4 testing, where can I get them?
- What treatment will control the disease during the weeks the cells are being made?
- How long do I need to stay near the hospital after the infusion?
- Are there clinical trials I could join in Japan or the US?
Frequently asked questions
Is immune cell therapy the same as immunotherapy drugs?
No. Immunotherapy drugs (PD-1 inhibitors such as Keytruda) release the brakes on the immune response. Immune cell therapy expands or modifies the cells themselves and puts them into the body. Some, like TIL, are given after immunotherapy drugs.
Does immune cell therapy work for solid tumors?
Treatments with proven effect are now available. In 2024 the US approved TIL for melanoma (tumor shrinkage in 31.5% of 73 patients) and TCR-T for synovial sarcoma (tumor shrinkage in 43% of 44 patients). Clinical trials in other solid tumors are active.
Is CAR-T covered by insurance in Japan?
Yes. Kymriah was first approved and covered in 2019, and other CAR-T products have been approved since. Eligible blood cancer patients are treated under insurance at facilities that meet the required standards.
Which is better, NK cell therapy or CAR-T?
They serve different purposes and are at different stages. CAR-T is an approved treatment shown to extend survival in certain blood cancers, while autologous NK cell therapy in Japan is offered as self-pay care. Which suits you is decided with your doctor based on cancer type, stage and prior treatment.
Related: CAR-NK vs CAR-T · NK cell therapy process · mRNA cancer vaccines · NK cell medical information
Sources
- Cancer Research Institute — Adoptive Cell Therapy (TIL, TCR, CAR T, NK)
cancerresearch.org
Checked: 2026-10-29 - AACR — FDA Approves First Tumor-infiltrating Lymphocyte Therapy (lifileucel, Amtagvi), February 2024
aacr.org
Checked: 2026-10-29 - CURE — FDA Approves Tecelra to Treat Synovial Sarcoma (SPEARHEAD-1), August 2, 2024
curetoday.com
Checked: 2026-10-29 - The ASCO Post — Overall Survival With Axicabtagene Ciloleucel in Large B-Cell Lymphoma: Results From ZUMA-7, July 2023
ascopost.com
Checked: 2026-10-29 - The ASCO Post — Anti-CD19 CAR-NK Therapy in Relapsed or Refractory CD19-Positive Lymphoid Tumors (Liu E, et al. NEJM 2020), February 2020
ascopost.com
Checked: 2026-10-29 - Fierce Pharma — Novartis’ Kymriah to be covered by Japan health insurance at $305K, 2019
fiercepharma.com
Checked: 2026-10-29
Written by the FTH editorial team. Sources checked 2026-10-29 · Medical review: not applicable
This article is general information based on public sources and does not replace diagnosis or treatment. Please discuss treatment decisions with your medical team.
