Table 1 Potency Tests Used for the 31 US FDA-Approved Cell Therapy Products (to date)

Hemacord (2011)

Allogeneic cord blood for hematopoietic and immunologic reconstitution in patients with disorders affecting the hematopoietic system that are inherited, acquired, or result from myeloablative treatment

FDA SBRA [14]: (i) Total nucleated cells (TNC); (ii) viability of CD45 + cells; (iii) viable CD34 + cell count; (iv) Colony forming unit (CFU)

Clinimmune (2012)

FDA SBRA: (i) Total nucleated cells (TNC); (ii) viability of total nucleated cells (TNC); (iii) viable CD34 + cell count; (iv) redacted

Ducord (2012)

FDA SBRA: (i) Total nucleated cells (TNC); (ii) viable nucleated cells; (iii) viable CD34 + cells (flow cytometry); (iv) redacted; (v) redacted

Lifesouth (2013)

FDA SBRA: (i) Total nucleated cells (TNC); (ii) viable nucleated cells; (iii) viable CD34 + cells (flow cytometry); (iv) redacted

Bloodworks (2016)

FDA SBRA: (i) Total nucleated cells (TNC); (ii) viable nucleated cells; (iii) viable CD34 + cells (flow cytometry); (iv) redacted

Allocord (2016)

FDA SBRA: (i) Total nucleated cells (TNC); (ii) viable nucleated cells; (iii) viable CD34 + cell count; (iv) colony forming units (CFU)

Clevecord (2016)

FDA SBRA: (i) Total nucleated cell number; (ii) viability of TNC; (iii) viable CD34 + cell count; (iv) redacted

MD Anderson (2018)

FDA SBRA: (i) Total CD34 + count; (ii) total nucleated cell (TNC) count (per HPC, cord blood); (iii) nucleated RBC; (iv) viability of nucleated cells; (v) viable CD34 + cells; (vi) colony forming unit (CFU) assay

Omisirge (2023)

Allogeneic umbilical cord blood (UCB) cells cultured in nicotinamide to improve stemness for patients with hematologic malignancies having UCB transplantation

FDA SBRA: CD34 + cell fold-increase

Kymriah (2017)

Autologous T-cells reprogrammed to target cells that express specific surface antigens for treating cancers (CAR T-cells)

FDA Advisory Committee Meeting [15]: i) CAR expression by flow cytometry; (ii) release of IFNγ in response to CD19-expressing target cells

Yescarta (2017)

FDA SBRA: (i) Cell viability; (ii) anti-CD19 CAR expression; (iii) redacted; Papadouli et al., 2020: Interferon-γ production by product upon stimulation with CD19 + cells [17]

Tecartus (2020)

FDA SBRA: (i) Cell viability; (ii) anti-CD19 CAR expression; (iii) redacted

Breyanzi (2021)

FDA SBRA: (i) Redacted

Abecma (2021)

FDA SBRA: (i) Redacted; EMA Assessment Report [18]: Interferon-γ production by product upon stimulation with BCMA + cells

Carvykti (2023)

FDA SBRA: (i) CAR expression from viable T cells; (ii) redacted

Aucatzyl (2024)

FDA SBRA: (i) Redacted

Tecelra (2024)

Autologous T cells genetically modified with lentiviral vector to express a T cell receptor (TCR) specific for human MAGE-A4 for treating synovial sarcoma

FDA SBRA: (i) Cytotoxic activity (cytotoxicity assay with flow cytometry)

Provenge (2010)

Autologous CD54 + cells activated with PAP-GM-CSF for prostate cancer

FDA SBRA: (i) Number of CD54 + cells (flow cytometry); (ii) increased expression of CD54 on the surface of antigen presenting cells after culture with PAP-GM-CSF (flow cytometry)

Laviv (2011)

Autologous fibroblasts from skin punch biopsy for nasolabial fold wrinkles

FDA SBRA: (i) Cell count; (ii) cell viability; (iii) collagen production by the cells

Gintuit (2012)

Allogeneic cultured keratinocytes and fibroblasts in bovine collagen for gingival defects

FDA SBRA: Histology with morphological assessments: epidermal coverage, epidermal development, basal cell layer keratinocyte viability, suprabasal cell layer keratinocyte viability, dermal thickness, fibroblast density, and matrix integrity

MACI (2016)

Autologous cultured chondrocytes on porcine collagen membrane for knee cartilage defects

FDA SBRA: (i) Cell number; (ii) redacted; (iii) redacted; Rapko et al. [19]: PCR measurement of aggrecan gene expression

Stratagraft (2021)

Allogeneic cultured keratinocytes and dermal fibroblasts in murine collagen for thermal burns

FDA SBRA: Redacted

Rethymic (2021)

Allogeneic processed thymus tissue for athymia

FDA SBRA: Histology-based (tissue organization, viability & retention of important cell types believed to be important for function)

Zynteglo (2022)

Autologous CD34 + cells hematopoietic stem cells (HSCs) transduced to express βA-T87Q-globin for ß-thalassemia

FDA SBRA: (i) Vector copy number (VCN) (qPCR); (ii) percent LVV + cells; (iii) redacted; (iv) redacted; (v) colony forming cells (CFC); (vi) βA-T87Q-globin quantitative protein expression

Skysona (2022)

Autologous CD34 + hematopoietic stem cells (HSCs) transduced with adrenoleukodystrophy protein (ALDP) for cerebral adrenoleukodystrophy (CALD)

FDA SBRA: (i) Vector copy number (VCN) (qPCR); (ii) percent LVV + cells; (iii) redacted; (iv) redacted; (v) redacted; (vi) percent ALDP + cells

Lantidra (2023)

Allogeneic pancreatic islet cellular therapy for Type 1 diabetes

FDA Advisory Committee Meeting [16]: (i) Glucose Stimulation Index (GSI): ELISA (enzyme linked immunosorbent assay) quantification of insulin release by glucose stimulated islets; (ii) Islet Yield: Dithizone (DTZ) stain and microscopic quantification; (iii) Viability: SYTO 13 green/ethidium bromide staining and microscopic evaluation

Casgevy (2023)

Autologous CD34 + HSCs gene edited to reduce BCL11A expression in erythroid lineage cells for treating ß-thalassemia in children

FDA SBRA: (i) On-target editing frequency (tracking of indels by decomposition, TIDE); (ii) redacted; (iii) redacted

Lyfgenia (2023)

Autologous HSCs containing functional copies of a modified β-globin gene for sickle cell disease

FDA SBRA: (i) Vector copy number (VCN); (ii) redacted, (iii) redacted; (iv) redacted; (v) redacted; (vi) βA-T87Q-globin quantitative protein expression

Amtagvi (2024)

Autologous T-cell therapy made of ex vivo-expanded lymphocytes harvested from patient tumors for melanoma

FDA SBRA: (i) redacted, (ii) redacted, (iii) redacted, (iv) redacted, (v) dose (total viable cells), (vi) redacted and (vii) redacted

Lenmeldy (2024)

Autologous HSCs expressing the human arylsulfatase (ARSA) gene for treating metachromatic leukodystrophy in children

FDA SBRA: (i) viability (%); (ii) vector copy number; (iii) vector copy number (calculation); (iv) transduction efficiency; (v) transgene function (arylsulfatase A (ARSA) activity); (vi) redacted; (vii) redacted; (viii) redacted

Ryoncil (2024)

Allogeneic culture-expanded MSCs isolated from the bone marrow of healthy human adult donors

FDA SBRA: (i) interleukin-2 receptor alpha (IL-2Rα) inhibition bioassay [20]; (ii) redacted; (iii) cell viability; (iv) cell concentration