A Phase 2 interventional study of Letetresgene autoleucel (lete-cel, GSK3377794) and Fludarabine in Neoplasms, sponsored by USWM CT, LLC. Active, not recruiting at 38 sites in 7 countries. Open to participants aged 10 Years and older. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by USWM CT, LLC · Phase 2, Interventional, and Treatment
This trial will evaluate safety and efficacy of human engineered T-cell therapies, in participants with advanced tumors.
New York esophageal antigen-1 (NY-ESO-1) and LAGE-1a antigens are tumor-associated proteins that have been found in several tumor types. Clinical trials using adoptively transferred T cells directed against NY-ESO-1/LAGE-1a have shown objective responses. Letetresgene autoleucel (lete-cel, GSK3377794) is the first generation of NY-ESO-1 specific T-cell receptor engineered T cells. This is a master protocol investigating T-cell therapies. It will initially consist of a core protocol with two independent substudies investigating Letetresgene autoleucel in previously untreated (1L) Human Leukocyte Antigen (HLA)-A*02+ participants with NY-ESO-1+ advanced (metastatic or unresectable) synovial sarcoma (SS) or myxoid/round cell liposarcoma (MRCLS) (Substudy 1) and Letetresgene autoleucel as second line or higher (2L+) treatment in HLA-A*02+ participants with NY-ESO-1+ advanced (metastatic or unresectable) SS or MRCLS who have progressed following treatment with anthracycline based chemotherapy (Substudy 2).
10,818 studies on the registry are indexed under Neoplasms; 2,324 are open to participants now.
This study's enrollment of 103 is above the median of 60 across 7,703 interventional studies indexed under Neoplasms.
Browse Neoplasms studies →USWM CT, LLC is the lead sponsor of 9 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Washout period
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Eligible participants will be leukapheresed to manufacture engineered T cells. Participants will then receive letetresgene autoleucel.
Drug: Letetresgene autoleucel (lete-cel, GSK3377794) · Drug: Fludarabine · Drug: Cyclophosphamide
Eligible participants will be leukapheresed to manufacture engineered T cells. Participants will then receive letetresgene autoleucel.
Drug: Letetresgene autoleucel (lete-cel, GSK3377794) · Drug: Fludarabine · Drug: Cyclophosphamide
letetresgene autoleucel will be administered.
Fludarabine will be used as the lymphodepleting chemotherapy
Cyclophosphamide will be used as the lymphodepleting chemotherapy.
Substudy 1: Overall response rate (ORR)
Overall response rate is defined as the percentage of participants with a confirmed complete response (CR) or partial response (PR) relative to the total number of participants within the analysis population at any time per Response Evaluation Criteria in Solid Tumors (RECIST) version (v) 1.1. as determined by the local investigators.
Time frame: Until disease progression (up to 5 years)
Substudy 2: Overall response rate (ORR) as assessed by central independent review
Overall response rate is defined as the percentage of participants with a confirmed CR or PR relative to the total number of participants within the analysis population at any time per RECIST v1.1. as assessed by central independent review.
Time frame: Up to 5 years
Substudy 1 and 2: Time to response (TTR)
Time to response is defined as time from date of T-cell administration to first documented evidence of confirmed (CR or PR) as assessed by local investigators per RECIST v1.1.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Duration of response (DOR)
Duration of response is defined as, in the subset of participants who show a confirmed CR or PR as assessed by local investigators, the time from first documented evidence of CR or PR until the first documented sign of disease progression or death.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Disease control rate (DCR)
Disease control rate is defined as the percentage of participants with a confirmed CR, PR, or stable disease (SD) with minimal 12 weeks duration relative to the total number of participants within the analysis population at the time of primary analysis as determined by Investigators per RECIST v1.1.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Progression free survival (PFS)
Progression free survival is defined as the time from the date of T-cell administration until first documented sign of disease progression per RECIST v1.1, or death.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Frequency of adverse events (AEs), serious adverse events (SAEs) and AEs of special interest (AESI) according to severity
AEs, SAEs and AESIs will be collected. Severity of AEs and SAEs will be summarized using National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE), version 5.0.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Number of participants with replication competent lentivirus (RCL)
RCL exposure will be assessed by polymerase chain reaction (PCR) based assay.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Number of participants with insertional oncogenesis (IO)
Peripheral blood mononuclear cells (PBMC) samples will be collected for monitoring insertional oncogenesis by PCR for gene modified cells in the blood.
Time frame: Until disease progression (up to 5 years)
Substudy 2: Number of participants with clinically significant changes in hematology, clinical chemistry and urinalysis parameters
Blood and urine samples will be collected for assessment of hematology, clinical chemistry and urinalysis parameters.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Maximum transgene expansion (Cmax) of letetresgene autoleucel
Whole blood samples will be collected at indicated time points for evaluation of Cmax.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Time to Cmax (Tmax) of letetresgene autoleucel
Whole blood samples will be collected at indicated time points for evaluation of Tmax.
Time frame: Until disease progression (up to 5 years)
Substudy 1 and 2: Area under the concentration/persistence time curve from zero to time t (AUC[0-t]) of letetresgene autoleucel
Whole blood samples will be collected at indicated time points for evaluation of AUC(0-t).
Time frame: Until disease progression (up to 5 years)
Substudy 2: Overall response rate (ORR) as determined by the local investigators
Overall response rate is defined as the percentage of participants with a confirmed CR or PR relative to the total number of participants within the analysis population at any time per RECIST v1.1. as determined by the local investigators.
Time frame: Up to 5 years
Substudy 2: Overall Survival (OS)
Overall Survival is defined as the interval of time between the date of T-cell infusion and the date of death.
Time frame: Up to 5 years
Substudy 2: Number of participants with positive anti-drug antibodies (ADA) and titers of ADA against letetresgene autoleucel
Serum samples will be collected to analyze for the presence of ADAs using validated immunoassays.
Time frame: Up to 36 months
Plan to share: No
No publications or documents are linked to this record.
Ran from Dec 2019 to primary completion in Mar 2024, 50 months.
Of 179 industry-sponsored phase 2 interventional studies under Neoplasms, half reached primary completion within 42 months of starting (the median), counting those still running; a quarter within 26 and three quarters within 68. This study's 50 months is above that.
Counting every sponsor, half of 514 studies reached it within 52 months; a quarter within 33 and three quarters within 92.
Neoplasms covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Letetresgene autoleucel
USWM CT, LLC