A Phase 1 interventional study of ST-01156 in Advanced Solid Tumors, Ewing Sarcoma and Hepatocellular Carcinoma (HCC), sponsored by SEED Therapeutics, Inc.. Recruiting at 6 sites in United States. Open to participants aged 16 Years and older. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by SEED Therapeutics, Inc. · Phase 1, Interventional, and Treatment
A Phase 1/1B Study of ST-01156 in Patients with Advanced Solid Malignancies
This Phase 1/1b study is evaluating the safety, tolerability, and preliminary anticancer activity of ST-01156 in participants with advanced solid malignancies. The study will be conducted in 2 parts. Part 1 (Dose Escalation) will assess the safety, tolerability, pharmacokinetics (PK) and preliminary anticancer activity of SD-01156 in participants with advanced solid malignancies, many of whom have a biological rationale to be targeted with an inhibitor of RBM39. Part 1 will also seek to determine the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) of ST-01156.
250 studies on the registry are indexed under Sarcoma, Ewing; 69 are open to participants now.
This study's planned enrollment of 171 is above the median of 36 across 204 interventional studies indexed under Sarcoma, Ewing.
Browse Sarcoma, Ewing studies →This is the only study on the registry with SEED Therapeutics, Inc. as lead sponsor.
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.
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.
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.
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.
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.
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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
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.
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.
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.
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.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ST-01156, administered orally once daily for 5 consecutive days followed by 2 days without study drug administration every 7 days
Drug: ST-01156
ST-01156 is an orally administered degrader of RBM39, a protein frequently upregulated in cancer
Part 1: Dose Escalation
To characterize the safety, tolerability, and adverse event (AE) profile of escalating doses of ST-01156 administered for 5 consecutive days followed by 2 days without study drug administration every 7 days, with a cycle defined as 28 days (4 weeks).
Time frame: First 28 days of treatment
Part 1: Dose Escalation
To identify the maximum tolerated dose (MTD) or maximum administered dose (MAD), and to recommend a dose for subsequent studies (recommended Phase 2 dose \[ RP2D\]) of ST-01156 on a daily oral schedule for 5 consecutive days out of every 7 days with a cycle defined as 28 days (4 weeks).
Time frame: Duration of treatment period
Part 1: Dose Escalation
To characterize the pharmacokinetics (PK) of ST-01156 administered on a daily oral schedule for 5 consecutive days every 7 days with cycle defined as 28 days (4 weeks). PK parameters will include area under the concentration-time curve (AUC), maximum observed concentration (Cmax), and time to observe maximum observed concentration (Tmax).
Time frame: First 28 days of treatment
Part 1: Dose Escalation
To detect preliminary evidence of antitumor activity in select advanced cancers where strong preclinical evidence of the anticancer activity of RBM39 degradation is strongest including: * Adults or adolescents with ES following disease progression or intolerance to therapeutics of reasonable likelihood of conferring clinical benefit. * aHCC following disease progression or intolerance to appropriate standard therapy for advanced disease. * KRASm solid malignancy of any type - locally advanced or unresectable solid malignancy following disease progression or intolerance to therapeutics or reasonable likelihood of conferring clinical benefit. * BTC, endometrial carcinoma, solid malignancies with pathogenic somatic or germline mutations in BCRA1/2 or HRR genes (BRCA1/2, PALB2, RAD51C, RAD51D, ATM, BARD1, BLM, BRIP 1, CDK12,FANCA, FANCC, FANCD2, FANCE, FANCF, FANCM, MRE11A, NBN (NBS1), RAD50, RAD51B and others as confirmed by a Clinical Laboratory Improvement Amendments \[CLIA\]-certified m
Time frame: Baseline and every 6 weeks thereafter until disease progression
Part 1: Dose Escalation
To evaluate the relationship between RBM39 degradation in peripheral blood mononuclear cells (PBMC) \[and potentially other cells or tissues\], to various safety and efficacy endpoints.
Time frame: Days 1, 2, 3, 4, 5, 8, 15, and 16 of the first two 28-day cycles of treatment, and days 1 of subsequent cycles, until permanent discontinuation of study treatment.
Plan to share: No
No publications or documents are linked to this record.
Started Dec 2025 (actual). Primary completion is estimated for Dec 2029, 48 months after the start.
Of 41 phase 1 interventional studies under Sarcoma, Ewing, half reached primary completion within 89 months of starting (the median), counting those still running; a quarter within 65 and three quarters within 134. This study's planned 48 months is below 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 ↗
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