Sponsor: Stanford University (other)
Phase: 1
Start date: Nov. 11, 2024
Planned enrollment: 48
B7-H3 CAR-T therapies are autologous or allogeneic chimeric antigen receptor T cells engineered to recognize B7-H3 (CD276), a checkpoint-like immunomodulatory molecule overexpressed across many solid tumors and associated with poor outcomes. Clinical-stage programs include TX103 for recurrent glioblastoma (rGBM) and a fourth‑generation construct 4SCAR‑276 being studied in B7‑H3–positive solid tumors. Interim human data have been presented for TX103 in rGBM; other programs (e.g., 4SCAR‑276) remain in early-phase evaluation without published response outcomes to date. (aacrjournals.org)
TX103 (autologous B7‑H3 CAR‑T; rGBM) - Study: Phase 1, single‑arm, dose‑escalation with intracavitary and/or intraventricular administration via Ommaya; NCT05241392. Interim ASCO 2024 abstract reported 13 treated patients between March 2022 and January 2024. (ascopubs.org) - Outcomes (interim): Among six patients from dose levels 1–2 evaluable for 12‑month survival as of January 2024, 12‑month OS was 83.3% (95% CI 58.3–100); median OS 20.3 months (95% CI 20.3–not reached). In dose level 2, two of three patients achieved partial and complete responses, respectively. CSF cytokines (e.g., IL‑6, IFN‑γ) and CAR transgene copies increased post‑infusion, with minimal peripheral changes. (ascopubs.org)
Allogeneic B7‑H3 CAR‑T in recurrent high‑grade glioma (for context; different product) - MT027 UCAR‑T IIT (ChiCTR2100047968): ASCO 2023/2024 abstracts reported favorable tolerability with no grade ≥3 toxicities; 12‑month OS 85.7% (95% CI 48.7–97.4) in one analysis; PK/PD showed CSF persistence and cytokine increases. These are single‑center, early‑phase data. (ascopubs.org)
4SCAR‑276 (B7‑H3 CAR‑T; fourth‑generation) - Multicenter Phase I/II trial in B7‑H3–positive solid tumors (NCT04432649) is listed; as of the latest registry snapshots, no results are posted. (cdek.pharmacy.purdue.edu)
TX103 (NCT05241392; interim)
- No dose‑limiting toxicities or treatment‑related deaths reported among 13 patients.
- Treatment‑related adverse events included cytokine release syndrome, increased intracranial pressure, headache, seizures, decreased consciousness, vomiting, and fever; most were grade 1–2. Three grade‑3 events occurred (increased intracranial pressure at dose level 2; seizure and decreased level of consciousness at dose level 3). (ascopubs.org)
Allogeneic B7‑H3 UCAR‑T (context) - Early reports noted no grade ≥3 toxicities, with most common events being fever and headache; no CRS/ICANS/GvHD observed in the presented dataset. (ascopubs.org)
Notes: Published evidence to date is primarily from conference abstracts and trial registries; peer‑reviewed, full clinical manuscripts for these specific products were not identified as of October 7, 2025.
Last updated: Oct 2025
Goal: Evaluate feasibility, safety, and define the MTD/RP2D of autologous B7-H3–directed CAR T cells delivered either intraperitoneally or intravenously for adults with recurrent, platinum‑refractory or ‑resistant ovarian cancer, and explore early antitumor activity.
Patients: Adults (≥18 years) with histologically or cytologically confirmed epithelial ovarian cancer (serous, endometrioid, clear cell, mucinous, mixed epithelial, or undifferentiated; carcinosarcoma allowed if predominantly high grade), measurable disease, ECOG 0–2, adequate organ function, and prior platinum-based therapy with platinum-refractory or -resistant status. Archival tissue or willingness to undergo biopsy is required for B7‑H3 expression analysis, though positivity is not mandatory. Key exclusions include active/uncontrolled infection, significant cardiovascular disease, active autoimmune disease, active HIV/HBV/HCV viremia, untreated or unstable brain metastases, recent high-dose steroids, GI fistula/perforation/abscess, and clinically significant seizure history.
Design: Single-site, open-label, nonrandomized phase 1 using a conventional 3+3 dose-escalation design in two administration cohorts (intraperitoneal and intravenous). Planned enrollment is 48. Dose-limiting toxicities are assessed through day 28 after infusion; expansion to at least 6 evaluable participants per arm for MTD/RP2D determination.
Treatments: Autologous B7-H3CART cells administered after lymphodepleting conditioning, delivered either intraperitoneally via a surgically or radiologically placed catheter for patients with disease confined to the peritoneum, or intravenously for patients with extra-peritoneal disease or unsuitable peritoneal anatomy. B7‑H3CART targets CD276 (B7‑H3), a pan‑cancer immunoregulatory antigen overexpressed on many solid tumors with limited normal tissue expression. The CAR comprises autologous T cells engineered with a second‑generation construct (typical costimulation domains include 4‑1BB or CD28) to redirect cytotoxicity against B7‑H3–expressing tumor cells. Early clinical experience with B7‑H3 CAR‑T in CNS malignancies and other solid tumors has shown feasibility and manageable safety with signals of activity in small cohorts, supporting evaluation in ovarian cancer.
Outcomes: Primary: feasibility of manufacturing runs meeting IND release criteria and target dose; MTD/RP2D in each arm based on day 28 DLTs. Secondary: objective response rate per RECIST at day 28 and duration of response up to 12 months.
Burden on patient: High. Participants undergo leukapheresis for autologous manufacturing, lymphodepleting chemotherapy, and CAR T infusion with close inpatient or intensive outpatient monitoring for cytokine release syndrome and neurotoxicity. The intraperitoneal arm requires laparoscopic or interventional radiology catheter placement and potential Tenckhoff catheter for ascites sampling, adding procedural risk and visits. Serial imaging for response, protocol-mandated labs, and potential on‑study tumor biopsy increase visit frequency and phlebotomy. Early phase monitoring commonly entails frequent clinic assessments in the first month and scheduled follow‑ups thereafter, which together exceed standard-of-care intensity for recurrent ovarian cancer.
Last updated: Oct 2025
Inclusion Criteria:
1. Disease: Histologically or cytologically confirmed diagnosis of ovarian cancer including serous, endometrioid, clear cell, mucinous, mixed epithelial, or undifferentiated. The study does not include pure sarcoma, stromal, or germ-cell tumors. Tumors that are substantially high-grade carcinoma and have focal elements of lower grade tumors or sarcomatous elements (e.g., carcinosarcoma) are eligible.
2. Have measurable disease. Measurable disease is defined as at least 1 lesion that can be accurately measured in at least 1 dimension (longest diameter to be recorded). Each lesion must be ≥10 mm when measured by CT, MRI, or caliper measurement at clinical examination or ≥20 mm when measured by chest x-ray. Lymph nodes must be ≥15 mm in short axis when measured by CT or MRI.
3. B7-H3 positive expression on malignant cells is NOT required but archival tissue must be available, or the subject must be willing to undergo tissue biopsy for expression analysis.
4. Age: ≥ 18 years of age
5. Prior Therapies: Subjects must have had at least 1 prior platinum-based chemotherapeutic regimen for the management of ovarian carcinoma.
Patients should be considered platinum- refractory (progression while on a prior platinum chemotherapy) or resistant (persistence or recurrence within 6 months after a prior platinum-based chemotherapy) after all available curative standard therapies. There is no limit to the number of prior therapies.
At least 3 weeks post chemotherapy or 5 half-lives, whichever is shorter, must have elapsed since any prior systemic therapy, except for systemic inhibitory/stimulatory immune checkpoint therapy that requires 3 months.
Must have recovered from prior therapy toxicities to grade 1 or baseline, except for peripheral neuropathies, alopecia, etc.
6. Performance Status: ECOG status of 2 or better (or Karnofsky Performance Status score of ≥60%) (See Section 11.1)
7. Life expectancy at least 3 months, in the investigator's clinical judgement.
8. Adequate bone marrow and major organ function.
* Hgb ≥ 10 g/dL
* ANC ≥ 1500/uL
* Platelet count ≥ 100,000/uL
* Absolute lymphocyte count ≥150/uL
* Creatinine ≤ 1.5 mg/dL or creatinine clearance ≥ 50 mL/min
* Serum ALT and AST ≤ 5x ULN (Grade 2)
* Total bilirubin ≤ 1.5x ULN (subjects with Gilbert's syndrome allowed if direct bilirubin within normal limits)
* PT or PTT ≤ 1.25 X ULN (not receiving therapeutic anticoagulation)
* Cardiac ejection fraction ≥ 45%
* No evidence of physiologically significant pericardial effusion
* No clinically significant ECG findings
* Baseline oxygen saturation \> 92% on room air
9. Pregnancy: Females of childbearing potential (defined as women ≤50 years of age, or \>50 years of age with a history of amenorrhea for ≤12 months prior to study entry) must have a negative blood or urine pregnancy test.
Subjects of child bearing potential must be willing to use an effective method of contraception (hormonal or two barrier methods) from the time of enrollment on this study and for at least four (4) months after receiving last dose of B7-H3CART cells or until CAR T cells are undetectable in peripheral blood.
10\. Consent: Must be able to understand and be willing to personally sign the written IRB approved informed consent document.
Exclusion Criteria:
* 1\. Active infection or uncontrollable infection requiring systemic treatment within 1 week before screening. Simple UTI and uncomplicated bacterial pharyngitis are permitted if responding to active treatment.
2\. Requirement for systemic corticosteroid therapy at doses higher than physiologic maintenance dosing (must be \< 5 mg/day of prednisone (or equivalent doses of other corticosteroids). Topical, inhaled or ocular steroids are allowed.
3\. Presence of abdominal fistula, gastrointestinal perforation, or intraabdominal abscess.
4\. Malignant tumors other than the target tumor within 2 years prior to screening, except for the following: malignant tumors that have received radical treatment and no known active disease within ≥ 2 years prior to enrollment; or adequately treated non-melanoma skin cancers with no evidence of disease.
5\. Have any of the following heart conditions:
• New York Heart Association (NYHA) stage III or IV congestive heart failure;
* Myocardial infarction or coronary artery bypass grafting (CABG) within 6 months before enrollment;
* Clinically significant ventricular arrhythmia, or a history of unexplained syncope (except those caused by vasovagal or dehydration);
* History of severe nonischemic cardiomyopathy. 6. Known to have active or uncontrolled autoimmune diseases, such as Crohns disease, rheumatoid arthritis, systemic lupus erythematosus, systemic vasculitis, etc.
7\. Ongoing HIV, HBV, or HCV infection. History of HBV or HCV is permitted if viral load is undetectable by qPCR and/or nucleic acid testing.
8\. Known or suspected untreated brain metastases. Patients with radiographically stable, asymptomatic previously irradiated lesions are eligible provided patient is \>4 weeks beyond completion of cranial irradiation and \>3 weeks off of corticosteroid therapy at the time of study intervention.
9\. Known sensitivities to any of the agents used in this study or their reagents including steroids, tocilizumab, DSMO, cyclophosphamide, fludarabine, etc.
10\. Prior history of clinically significant seizure disorder (e.g., not including childhood febrile seizures).
11\. Any other issue which, in the opinion of the treating physician or principal investigator, would make the patient ineligible for the study.
Palo Alto, California, 94304, United States
[email protected] / 650-723-0594
Status: Recruiting