A Phase 1 interventional study of P-MUC1C-ALLO1 CAR-T cells and Rimiducid in Breast Cancer, Ovarian Cancer and Non Small Cell Lung Cancer, sponsored by Poseida Therapeutics, Inc.. Active, not recruiting at 14 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by Poseida Therapeutics, Inc. (part of Hoffmann-La Roche) · Phase 1, Interventional, and Treatment
A Phase 1, open label, dose escalation and expanded cohort study of P-MUC1C-ALLO1 in adult subjects with advanced or metastatic epithelial derived solid tumors, including but not limited to the tumor types listed below.
This is an open label, multi-center Phase 1 study that will follow a 3 + 3 design of dose-escalating cohorts of single and multiple doses of P-MUC1C-ALLO1 to determine a Recommended Phase 2 Dose (RP2D). P-MUC1C-ALLO1 is an allogeneic chimeric antigen receptor (CAR) T cell therapy designed to target cancer cells expressing Mucin1 cell surface associated C-Terminal (MUC1-C) antigen. Additional participants will be treated with P-MUC1C-ALLO1 at the determined RP2D.
Following enrollment, subjects will be treated with P-MUC1C-ALLO1 and will undergo serial measurements of safety, tolerability and response. Rimiducid may be administered as indicated.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 180 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Poseida Therapeutics, Inc. is the lead sponsor of 6 studies on the registry; none are open to participants now.
First submitted before Poseida Therapeutics, Inc. became part of Hoffmann-La Roche.
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 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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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.
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 biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
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.
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.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
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.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
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.
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.
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.
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.
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.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
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.
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.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
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.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
* Single ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following lymphodepletion regimen 1. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Cyclic administration of ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following lymphodepletion regimen 1. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Single ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following lymphodepletion regimen 2. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Cyclic administration of ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following lymphodepletion regimen 2. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Single ascending A1 dose cohorts, given in a single intravenous infusion of CAR-T cells, following lymphodepletion regimen 1. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Single ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following assigned lymphodepletion regimen. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Cyclic administration of ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following assigned lymphodepletion regimen. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
* Single ascending dose cohorts, given in a single intravenous infusion of CAR-T cells, following assigned lymphodepletion regimen. * Rimiducid may be administered as indicated.
Biological: P-MUC1C-ALLO1 CAR-T cells · Drug: Rimiducid
P-MUC1C-ALLO1 is an allogeneic CAR-T cell therapy designed to target cancer cells expressing MUC1-C.
Rimiducid (safety switch activator) may be administered as indicated.
Determine the maximum tolerated dose (MTD) and/or recommended phase 2 dose (RP2D) of P-MUC1C-ALLO1
Number of subjects with a dose limiting toxicity (DLT)
Time frame: Baseline through Day 28
Evaluate the overall safety and tolerability profile of P-MUC1C-ALLO1
Frequency and severity of adverse events
Time frame: Baseline through 15 years
Evaluate the preliminary efficacy of P-MUC1C-ALLO1
According to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, secondarily Immune Response Evaluation Criteria in Solid Tumors (iRECIST): Overall Response Rate (ORR)
Time frame: Baseline through 15 years
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 Nov 2026. You cannot join it, but the record below documents what was studied.
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