A Phase 1/2 interventional study of ONO-4538HSC in Pediatric Malignant Solid Tumor and Epithelioid Sarcoma, sponsored by Ono Pharmaceutical Co., Ltd.. Recruiting at 15 sites in Japan. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2026-10-06.
Sponsored by Ono Pharmaceutical Co., Ltd. · Phase 1/2, Interventional, and Treatment
This is a multicenter, open-label, uncontrolled Phase I/II study to evaluate the efficacy, safety, and pharmacokinetics of ONO-4538HSC in pediatric patients with malignant solid tumors and in patients with epithelioid sarcoma, and to evaluate the tolerability in pediatric patients. The objective of this study is to explore the tolerability, safety, efficacy, and pharmacokinetics of ONO-4538HSC in patients with pediatric malignant solid tumors. The other objective is to exploratively investigate the efficacy and safety of ONO-4538HSC in patients with epithelioid sarcoma.
1,607 studies on the registry are indexed under Sarcoma; 366 are open to participants now.
This study's planned enrollment of 50 is above the median of 40 across 1,255 interventional studies indexed under Sarcoma.
Browse Sarcoma studies →Ono Pharmaceutical Co., Ltd. is the lead sponsor of 49 studies on the registry; 18 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.
[Cohort of pediatric malignant solid tumor Tolerability evaluation part]
Patients with PS of 0 to 1
[Cohort of pediatric malignant solid tumor Expansion part]
Patients with ECOG PS of 0 to 2
[Cohort of Epithelioid Sarcoma]
Patients with ECOG PS of 0 to 2
[Common]
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
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.
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.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
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.
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.
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.
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.
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.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PD-1, PD-L1 and checkpoint inhibitors
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: ONO-4538HSC
ONO-4538HSC will be administered subcutaneously once every 4 weeks.
Adverse events meeting protocol-defined criteria for a DLT
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: 28 days
Serious adverse events
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: UP to 100 days after the last dose
Adverse events
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: UP to 100 days after the last dose
Response rate (central assessment)
Cohort of Epithelioid Sarcoma
Time frame: Through study completion, an average of 6 months
Serum concentration of nivolumab
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Up to Cycle25 (each cycle is 28 days) and Post-treatment observation phase (28 days after the end of treatment phase)
Response rate (investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Progression-free survival (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Disease control rate (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Duration of response (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Time to response (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Best overall response (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Maximum percent change from baseline in the sum of diameters of target lesions (central assessment and investigator assessment)
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Changes in tumor markers over time
Cohort of epithelioid sarcoma
Time frame: Through study completion, an average of 6 months
Adverse events
Cohort of epithelioid sarcoma
Time frame: UP to 100 days after the last dose
Serum concentration of nivolumab
Cohort of epithelioid sarcoma
Time frame: Up to Cycle25 (each cycle is 28 days) and Post-treatment observation phase (28 days after the end of treatment phase)
Response rate (central assessmen and assessment by site investigator [hereinafter,investigator assessment])
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Overall survival
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Progression-free survival (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Disease control rate (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Duration of response (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Time to response (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Best overall response (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Percent change from baseline in the sum of tumor diameters of target lesions (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Maximum percent change from baseline in the sum of diameters of target lesions (central assessment and investigator assessment)
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Changes in tumor markers over time
Cohort of Patients with Pediatric Malignant Solid Tumor
Time frame: Through study completion, an average of 6 months
Analysis of efficacy, etc. with PD-L1 expression (measured at the central laboratory) and collected parameters
Common to both cohorts
Time frame: Screening
Anti-nivolumab antibody
Common to both cohorts
Time frame: Up to Cycle25 (each cycle is 28 days) and Post-treatment observation phase (28 days after the end of treatment phase)
Anti-rHuPH20 antibodies
Common to both cohorts
Time frame: Up to Cycle25 (each cycle is 28 days) and Post-treatment observation phase (28 days after the end of treatment phase)
Plan to share: No
No publications or documents are linked to this record.
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 ↗
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