A Phase 2 interventional study of Atezolizumab and Biopsy Procedure in Advanced Rare Malignant Solid Neoplasm, Rare Malignant Solid Neoplasm and Refractory Rare Malignant Solid Neoplasm, sponsored by National Cancer Institute (NCI). Active, not recruiting at 3 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-11-25.
Sponsored by National Cancer Institute (NCI) · Phase 2, Interventional, and Treatment
This phase II trial tests how well atezolizumab works in combination with tiragolumab in treating patients with rare solid tumors that may have spread from where they first started to nearby tissue, lymph nodes, or distant parts of the body (advanced stage). Immunotherapy with monoclonal antibodies, such as atezolizumab and tiragolumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. The study biopsy takes small pieces of cancer tissue from a tumor. The purpose of these biopsies is to compare the body's immune response against the tumor before and after treatment with the study drugs. Blood samples will also be collected for the study. The researchers will use the samples to learn more about how atezolizumab and tiragolumab work and which patients in the future might be most likely to respond to atezolizumab and tiragolumab. Using atezolizumab in combination with tiragolumab may help to shrink tumors in patients diagnosed with advanced stage rare solid-tumor cancers.
PRIMARY OBJECTIVE:
I. Determine the proportion of activated CD8+ T cells at baseline and after treatment with atezolizumab and tiragolumab.
SECONDARY OBJECTIVES:
I. Determine the objective response rate (ORR) of patients with advanced rare cancers to the combination of atezolizumab and tiragolumab using Response Evaluation Criteria in Solid Tumors (RECIST) version (v) 1.1 and Immune-Modified (i)RECIST guidelines.
II. Measure progression-free survival (PFS) time (time frame: baseline until disease progression, death, loss to follow-up, initiation of another anti-cancer treatment, withdrawal of consent, or study termination).
III. Measure the proportion of patients with a clinically promising increase in CD8+ T cell infiltration following treatment with atezolizumab and tiragolumab.
EXPLORATORY OBJECTIVES:
I. Investigate immune activation markers and the immune composition (regulatory T [Treg], natural killer [NK], B-cells, macrophages, myeloid-derived suppressor cells [MDSC], tumor mutation burden [TMB], microsatellite instability [MSI]) in tumor microenvironment (TME) before and after study treatment.
II. Measure T cell receptor (TCR) signaling in tumor-infiltrating T cells in the TME as well as in circulating T cells in blood before and after study treatment using multiplex immunofluorescence assays (IFAs)-developed by the National Cancer Institute (NCI)-Frederick Pharmacodynamic Assay Development \& Implementation Section (PADIS)-and use these measurements to evaluate the relationship between TCR signaling in circulating T cells and TME.
III. Evaluate potential associations between atezolizumab and tiragolumab activity and tumor genomic alterations, genomic expression, or TMB as determined from genomic analysis of biopsy samples.
IV. Evaluate genomic alterations in cell free deoxyribonucleic acid (DNA) (cfDNA) and their potential association with therapy response or resistance.
V. Evaluate the pharmacodynamic effects of the treatment on biomarkers of cell death and epithelial-to-mesenchymal transition (EMT) in tumor tissue and circulating tumor cells (CTCs).
VI. Evaluate markers of immune response and the presence of tertiary lymphoid structures (TLS) in TME at baseline and following atezolizumab plus tiragolumab therapy.
OUTLINE:
Patients receive atezolizumab intravenously (IV) over 60 minutes and tiragolumab IV over 30-90 minutes on day 1 of each cycle. Cycles repeat every 21 days in the absence of disease progression or unacceptable toxicity. Patients also undergo echocardiography (ECHO) at baseline, undergo biopsy at baseline and on study, and undergo computed tomography (CT) and collection of blood samples throughout the study.
After completion of study treatment, patients are followed up for 30 days.
National Cancer Institute (NCI) is the lead sponsor of 3,506 studies on the registry; 334 are open to participants now.
Of its 402 completed or terminated interventional studies of FDA-regulated products, 365 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients must have histologically confirmed rare solid tumors that have progressed on standard therapy or for whom there is no standard of care therapy
International normalized ratio (INR) or activated partial thromboplastin time (aPTT) =\< 1.5 institutional upper limit of normal (ULN)
Exclusion Criteria:
Treatment with systemic immunosuppressive medications (including, but not limited to, prednisone [> 10 mg/day], cyclophosphamide, azathioprine, methotrexate, thalidomide, and anti-tumor necrosis factor [anti-TNF] agents) within 2 weeks prior to Cycle 1, Day 1
History or risk of autoimmune disease, including, but not limited to, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, vascular thrombosis associated with antiphospholipid syndrome, Wegener's granulomatosis, Sjogren's syndrome, Bell's palsy, Guillain-Barre syndrome, multiple sclerosis, autoimmune thyroid disease, vasculitis, or glomerulonephritis
Patients with eczema, psoriasis, lichen simplex chronicus, or vitiligo with dermatologic manifestations only (e.g., patients with psoriatic arthritis would be excluded) are permitted provided that they meet the following conditions
Administration of a live, attenuated vaccine within 4 weeks before Cycle 1, Day 1 or anticipation that such a live, attenuated vaccine will be required during the study and up to 5 months after the last dose of atezolizumab
Patients receive atezolizumab IV over 60 minutes and tiragolumab IV over 30-90 minutes on day 1 of each cycle. Cycles repeat every 21 days in the absence of disease progression or unacceptable toxicity. Patients also undergo ECHO at baseline, undergo biopsy at baseline and on study, and undergo CT and collection of blood samples throughout the study.
Biological: Atezolizumab · Procedure: Biopsy Procedure · Procedure: Biospecimen Collection · Procedure: Computed Tomography · Procedure: Echocardiography Test · Drug: Tiragolumab
Given IV
Also known as: MPDL 3280A, MPDL 328OA, MPDL-3280A, MPDL3280A, MPDL328OA, RG 7446, RG-7446, RG7446, RO 5541267, RO-5541267, RO5541267, Tecentriq
Undergo tumor biopsy
Also known as: Biopsy, BIOPSY_TYPE, Bx
Undergo blood sample collection
Also known as: Biological Sample Collection, Biospecimen Collected, Specimen Collection
Undergo CT scan
Also known as: CAT, CAT Scan, Computed Axial Tomography, Computerized Axial Tomography, Computerized axial tomography (procedure), Computerized Tomography, Computerized Tomography (CT) scan, CT, CT Scan, Diagnostic CAT Scan, Diagnostic CAT Scan Service Type, tomography
Undergo ECHO
Also known as: EC, Echocardiography
Given IV
Change in the proportion of active CD8+ T cells infiltrating the tumor
Time frame: At baseline and beginning of cycle 3
Pharmacodynamic (PD) response rate
The proportion of patients with a clinically promising increase in CD8+ T cell infiltration, defined as more than 1.5 standard deviations (SD) (as measured at baseline).
Time frame: At baseline, end of cycle 3, then every 2-4 cycles until disease progression
Incidence of adverse events
Reported using the common terminology criteria for adverse events version 5.0.
Time frame: Cycle 1 day 1 to 30 days after last dose
Objective tumor response rate (ORR)
Fifteen enrolled patients will yield 10 patients with evaluable paired biopsies with .95 probability, yielding 88% power, at the 1-sided .05 significance level, to detect an increase more than 1.25 SD (as measured at baseline), and to declare the combination promising with respect to the primary PD endpoint. This number will also be sufficient for assessment of the secondary endpoint of ORR; there will be 96.5% likelihood of seeing at least 1 objective tumor response assuming a true ORR of 20%. Patients who do not achieve at least an unconfirmed response within 9 months (must be subsequently confirmed) will be considered non-responders for purposes of this analysis.
Time frame: Up to 2 years
Progression-free survival time
Time frame: Time from start of treatment to time of progression or death, whichever occurs first, assessed up to 2 years
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — "NCI is committed to sharing data in accordance with NIH policy. For more details on how clinical trial data is shared, access the link to the NIH data sharing policy page."
This study is active, not recruiting, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
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