Types of Cell Therapies: A Comprehensive Guide for Biopharma Leaders

Cell therapies use living cells as the medicine. In less than a decade they have gone from experimental to standard of care for some blood cancers, and they are now moving into solid tumours, autoimmune disease and regenerative medicine. They are not one technology, though. Each type has its own biology, manufacturing model, regulatory path and commercial challenges.

This guide covers the main types of cell therapy, how they work, where they stand clinically and what each one means for manufacturing, regulation and strategy. It is written for biopharma leaders and investors evaluating programs, partners or service providers in the space.

The Landscape at a Glance

Type	Cell source	Engineered?	Main uses	Status
CAR-T	Patient (mostly) or donor T cells	Yes, synthetic receptor	B-cell cancers, myeloma	Multiple FDA approvals
TCR-T	Patient T cells	Yes, natural-type TCR	Solid tumours	First approval 2024 (Tecelra)
TIL	Patient’s own tumour lymphocytes	No, selected and expanded	Melanoma, other solid tumours	First approval 2024 (Amtagvi)
NK cells	Blood, cord blood, iPSC or cell lines	Optional (CAR-NK)	Blood cancers, solid tumours	Clinical trials
HSC transplant	Patient or matched donor	Usually no	Blood cancers, marrow failure, genetic disease	Long-established standard of care
MSC	Bone marrow, fat, cord tissue	No	GVHD, inflammation, tissue repair	First US approval 2024 (Ryoncil)
iPSC-derived	Reprogrammed stem cell lines	Often	Regenerative medicine, off-the-shelf immune cells	Early clinical

Autologous or Allogeneic?

The single biggest strategic choice is whether cells come from the patient (autologous) or a donor (allogeneic). Autologous products avoid rejection and have the most regulatory precedent, but every patient is a separate batch, with weeks of manufacturing, strict chain of custody and high cost of goods. Allogeneic, “off-the-shelf” products can be made in large batches and given immediately, but must manage rejection and graft-versus-host disease, often through gene editing.

“Autologous versus allogeneic shapes almost everything that follows: cost, logistics, scalability and regulatory risk.”

Engineered and Expanded Immune Cells

CAR-T

T cells are collected from the patient, engineered to express a chimeric antigen receptor (an antibody-derived binding domain linked to T-cell signalling domains), expanded and infused back. Approved products target CD19 (leukaemias and lymphomas) and BCMA (multiple myeloma), and some patients achieve remissions lasting years. The challenges are cytokine release syndrome, neurotoxicity (ICANS), cost, manufacturing time and, above all, solid tumours, where target heterogeneity and a hostile tumour environment limit efficacy.

TCR-T

TCR-T cells are engineered with T-cell receptors that recognise peptides presented on HLA molecules. Because about 90% of proteins are intracellular, this opens up targets CAR-T cannot reach. The trade-offs are HLA restriction (each product suits only patients with a matching HLA type) and the risk of cross-reactivity with normal tissue. Targets include MAGE-A4, NY-ESO-1 and viral antigens such as HPV E7. The first approval, Adaptimmune’s Tecelra (afamitresgene autoleucel) for synovial sarcoma, came in August 2024.

Tumour-Infiltrating Lymphocytes (TIL)

TIL therapy isolates the T cells that have already infiltrated a patient’s tumour, expands them to billions over several weeks and reinfuses them after lymphodepleting chemotherapy, usually with IL-2. No genetic engineering is involved. Studies in heavily pretreated melanoma have shown meaningful response rates, and Iovance’s Amtagvi (lifileucel) became the first approved TIL therapy in February 2024. Manufacturing depends on surgery and on getting enough cells from each tumour.

Natural Killer (NK) Cells

NK cells are innate immune cells that kill tumour cells without prior sensitisation or HLA matching, and are activated when tumours hide from T cells by down-regulating MHC class I. CAR-NK combines that with CAR targeting. NK products carry a lower risk of cytokine release syndrome and graft-versus-host disease, so they suit allogeneic, off-the-shelf use from cord blood, iPSCs or cell lines. All remain in clinical development.

Stem Cell Therapies

Hematopoietic Stem Cell Transplantation

HSC transplantation is the oldest and most widely used cell therapy. Autologous transplants rescue the bone marrow after high-dose chemotherapy in myeloma and lymphoma. Allogeneic transplants from a matched donor also add a graft-versus-tumour effect, offering potential cures for acute leukaemias, at the risk of graft-versus-host disease. Better HLA typing, reduced-intensity conditioning and haploidentical (half-matched family) donors have widened access.

Mesenchymal Stromal Cells (MSC)

MSCs work mainly by releasing factors that calm inflammation and support repair, rather than by becoming new tissue. They have been studied in graft-versus-host disease, inflammatory bowel disease, cardiac and orthopaedic conditions, with mixed results driven partly by variable sourcing, manufacturing and potency. In December 2024 the FDA approved Mesoblast’s Ryoncil (remestemcel-L) for paediatric steroid-refractory acute GVHD, the first MSC therapy approved in the US.

IPSC-Derived Therapies

Induced pluripotent stem cells can be turned into almost any cell type, including cardiomyocytes, dopaminergic neurons, beta cells, and T or NK cells, from a single renewable, engineerable master cell line. That solves the scalability problem of primary cells, but raises others: complete differentiation, teratoma risk, functional maturity and complex regulation. Most programs are in early clinical trials. Banking and characterising these lines draws on the same disciplines as cell line development.

Manufacturing and Quality

Living cells are variable, sensitive to handling and hard to characterise, so CMC (chemistry, manufacturing and controls) is often the hardest part of a cell therapy program. Setting specifications, building stability programs and, above all, developing meaningful potency assays are recurring challenges. Products cannot be terminally sterilised, so aseptic processing, cleanroom control (see our cleanroom construction guide) and rapid release testing such as mycoplasma testing are critical.

Manufacturing models range from centralised plants to decentralised and point-of-care production, with closed, automated systems improving consistency and cost. Many developers rely on specialised CDMOs, which makes cell therapy a significant driver of demand for contract manufacturing, testing and qualification services.

Regulation

In the US, most cell therapies are regulated as biologics under the Public Health Service Act and need an IND and a BLA. Minimally manipulated products for homologous use may follow a lighter pathway, but most modern therapies involve substantial manipulation. The 21st Century Cures Act created the Regenerative Medicine Advanced Therapy (RMAT) designation to speed development of products for serious conditions.

Where the Field Is Heading

• Solid tumours: armoured CARs that secrete cytokines or resist checkpoint signals, and multi-antigen targeting to prevent antigen escape.
• Autoimmune disease: CD19 CAR-T is showing encouraging early results in conditions such as lupus, opening a large new market.
• Off-the-shelf products: gene-edited allogeneic CAR-T, CAR-NK and iPSC-derived cells aim to cut cost and wait times.
• In vivo CAR-T: engineering T cells inside the patient using viral or lipid nanoparticle delivery could remove ex vivo manufacturing entirely. It drew major pharma deals in 2025.
• Automation and AI to improve manufacturing consistency, predict product quality and enable point-of-care production.

What This Means for Biopharma Leaders and Investors

Each modality has a different risk profile, and the winners will combine strong biology with manufacturable, reimbursable products. When evaluating a program, partner or service provider, we’d focus on:

• Is the modality right for the indication: autologous or allogeneic, engineered or not, liquid or solid tumour?
• How robust is the CMC package: potency assay, comparability, release testing and vein-to-vein time?
• What is the cost of goods, and is there a credible path to reducing it at scale?
• Is the manufacturing strategy (in-house, CDMO or point of care) matched to the commercial plan?
• How differentiated is the product in crowded areas such as CD19 and BCMA?
• For service providers: how exposed is revenue to the funding cycle and to a small number of cell therapy clients?

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