A Phase 1 interventional study of second generation 4-1BBζ EGFR806-EGFRt and second generation 4-1BBζ EGFR806-EGFRt and a second generation 4 1BBζ CD19-Her2tG in Pediatric Solid Tumor, Germ Cell Tumor and Retinoblastoma, sponsored by Seattle Children's Hospital. Active, not recruiting at 1 site in United States. Open to participants aged 1 Year to 30 Years. Per ClinicalTrials.gov, last updated 2026-10-08.
Sponsored by Seattle Children's Hospital · Phase 1, Interventional, and Treatment
This is a phase I, open-label, non-randomized study that will enroll pediatric and young adult research participants with relapsed or refractory non-CNS solid tumors to evaluate the safety, feasibility, and efficacy of administering T cell products derived from the research participant's blood that have been genetically modified to express a EGFR-specific receptor (chimeric antigen receptor, or CAR) that will target and kill solid tumors that express EGFR and the selection-suicide marker EGFRt. EGFRt is a protein incorporated into the cell with our EGFR receptor which is used to identify the modified T cells and can be used as a tag that allows for elimination of the modified T cells if needed. On Arm A of the study, research participants will receive EGFR-specific CAR T cells only. On Arm B of the study, research participants will receive CAR T cells directed at EGFR and CD19, a marker on the surface of B lymphocytes, following the hypothesis that CD19+ B cells serving in their normal role as antigen presenting cells to T cells will promote the expansion and persistence of the CAR T cells. The CD19 receptor harbors a different selection-suicide marker, HERtG. The primary objectives of the study will be to determine the feasibility of manufacturing the cell products, the safety of the T cell product infusion, to determine the maximum tolerated dose of the CAR T cells products, to describe the full toxicity profile of each product, and determine the persistence of the modified cell in the subject's body on each arm. Subjects will receive a single dose of T cells comprised of two different subtypes of T cells (CD4 and CD8 T cells) felt to benefit one another once administered to the research participants for improved potential therapeutic effect. The secondary objectives of this protocol are to study the number of modified cells in the patients and the duration they continue to be at detectable levels. The investigators will also quantitate anti-tumor efficacy on each arm. Subjects who experience significant and potentially life-threatening toxicities (other than clinically manageable toxicities related to T cells working, called cytokine release syndrome) will receive infusions of cetuximab (an antibody commercially available that targets EGFRt) or trastuzumab (an antibody commercially available that targets HER2tG) to assess the ability of the EGFRt on the T cells to be an effective suicide mechanism for the elimination of the transferred T cell products.
166 studies on the registry are indexed under Neoplasms, Germ Cell and Embryonal; 48 are open to participants now.
This study's planned enrollment of 44 is above the median of 36 across 124 interventional studies indexed under Neoplasms, Germ Cell and Embryonal.
Browse Neoplasms, Germ Cell and Embryonal studies →Seattle Children's Hospital is the lead sponsor of 215 studies on the registry; 44 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.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
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.
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.
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
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.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
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.
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.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
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.
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.
GVHD (graft-versus-host disease)
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
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.
Autologous CD4+ and CD8+ T cells that have been genetically modified to express the EGFR 806CAR(2G) -EGFRt
Biological: second generation 4-1BBζ EGFR806-EGFRt
Autologous CD4+ and CD8+ T cells that have been genetically modified to express the EGFR806CAR(2G)-EGFRt and CD19CAR(2G)-T2A-HER2tG
Biological: second generation 4-1BBζ EGFR806-EGFRt and a second generation 4 1BBζ CD19-Her2tG
Autologous CD4 and CD8 T cells lentivirally transduced to express a second generation 4-1BBζ EGFR806-EGFRt
Autologous CD4 and CD8 T cells lentivirally transduced to express a second generation 4-1BBζ EGFR806-EGFRt and a second generation 4 1BBζ CD19-Her2tG
Estimate the maximum tolerated dose (MTD) or biologically effective dose and dose limiting toxicities (DLT), and describe the full toxicity profile of the two CAR T cell products
Type, frequency, severity, and duration of adverse events will be tabulated and summarized
Time frame: 28 days
The number of successfully manufactured EGFR806 and EGFR806xCD19 CAR T cell products will be assessed
The number of successfully manufactured products will be measured
Time frame: 28 Days
Establish the safety, defined by adverse events, of EGFR806-specific CAR T cell infusions (Arm A), and of dual transduced EGFR806xCD19 CAR T cell infusions (Arm B)
Type, frequency, severity, and duration of adverse events will be tabulated and summarized
Time frame: 28 Days
Number of Arm A and Arm B subjects with persistence of CAR T cells in the peripheral blood at each visit time point
Presence of CAR T cells in the peripheral blood will be assessed
Time frame: 84 Days
Number of Arm A and Arm B subjects with persistence of CAR T cells in the bone marrow at each visit time point
Presence of CAR T cells in the bone marrow will be assessed
Time frame: 84 days
To quantitate anti-tumor responses by measuring changes in tumor burden using disease-specific evaluations and describe survival characteristics following CAR T cell infusion
Standard imaging and bone marrow pathology will be used to determine disease response
Time frame: 84 Days
Plan to share: No
Started Jun 2019 (actual). Primary completion is estimated for Jun 2040, 252 months after the start.
Of 24 phase 1 interventional studies under Neoplasms, Germ Cell and Embryonal, half reached primary completion within 77 months of starting (the median), counting those still running; a quarter within 57 and three quarters within 92. This study's planned 252 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Neoplasms, Germ Cell and Embryonal →