ClinicalTrials.gg
TerminatedNCT05355753Updated Dec 17, 2024

A Study to Assess the Safety and Tolerability of CFT8634 in Locally Advanced or Metastatic SMARCB1-Perturbed Cancers, Including Synovial Sarcoma and SMARCB1-Null Tumors

A Phase 1 interventional study of CFT8634 in Synovial Sarcoma and Soft Tissue Sarcoma, sponsored by C4 Therapeutics, Inc.. Terminated at 12 sites in United States. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2024-12-17.

Sponsored by C4 Therapeutics, Inc. · Phase 1, Interventional, and Treatment

Why this study was terminated
High levels of BRD9 degradation did not result in sufficient efficacy in heavily pre-treated synovial sarcoma and SMARCB1-null solid tumor patients treated with CFT8634 as a single agent.

From the registry’s dates

  • Primary completion was Dec 2023, 2 years 10 months ago, and no results have been posted to the registry.
Phase
Phase 1
Study type
Interventional
Enrollment
49
Allocation
Non-randomized
Ages
12 Years and older
Sex
All
01

Study summary

This is an open-label, non-randomized, first-in-human Phase 1/2 study designed to evaluate the safety and tolerability of CFT8634 in subjects with synovial sarcoma and SMARCB1-null tumors who: have received prior systemic therapy; have relapsed/refractory tumors; have unresectable or metastatic disease; and are not candidates for available therapies known to confer clinical benefit. The study will characterize the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of CFT8634.

Read the detailed description

The study was intended to be Phase 1/2 trial but did not advance to Phase 2.

02

Conditions studied

  • Synovial Sarcoma
  • Soft Tissue Sarcoma

Keywords

  • Synovial Sarcoma
  • SMARB1-Null Tumors
  • CFT8634
  • Soft Tissue Sarcoma
  • Myoepithelial Carcinoma
  • Extraskeletal Myxoid Chondrosarcoma
  • Renal Medullary Carcinoma
  • Chordoma
  • Epithelioid Sarcoma
03

In context

Sarcoma, Synovial

133 studies on the registry are indexed under Sarcoma, Synovial; 29 are open to participants now.

This study's enrollment of 49 is close to the median of 46 across 117 interventional studies indexed under Sarcoma, Synovial.

Browse Sarcoma, Synovial studies →

Lead sponsor

C4 Therapeutics, Inc. is the lead sponsor of 5 studies on the registry; 2 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
12 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

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.

Inclusion criteria

  1. Subject (and legal guardian where applicable) is (are) willing and able to provide signed (or assent, where applicable) and can follow protocol requirements
  2. Subject has or cytologically confirmed synovial sarcoma or SMARCB1-null sold tumor that is , and unresectable or ; the subject must not be a candidate for available therapies that are known to confer clinical benefit

    a. Phase 1: subject must have received ≥1 prior line of systemic anticancer therapy considered to be Standard of Care per the Investigator's judgment, in the metastatic or unresectable setting b. Phase 2: i. Arm A: subject must have received only 1-2 prior lines of systemic anticancer therapy considered to be Standard of Care per the Investigator's judgment, in the metastatic or unresectable setting ii. Arm B: subject must have received ≥1 prior line of systemic anticancer therapy considered to be Standard of Care per the Investigator's judgment, in the metastatic or unresectable setting

  3. Subject must be:

    • ≥18 years of age (no minimum weight),
    • ≥16 and \<18 years old and weighs ≥50 kg,
    • ≥12 and \<16 years of age and weighs ≥40kg,
    • or ≥16 and \<18 years of age and weighs ≥40kg and \<50kg
  4. Subject must be able to safely swallow capsules
  5. Subject must have as defined by v1.1
  6. Subject must have performance status ≤2 or Lansky performance scale (LK scale) ≥ 60
  7. Subject must have adequate organ function, defined as:

    1. Bone marrow function: ≥1.0 x 109/L independent of growth factor support for ≤7 days prior to first dose of study drug for granulocyte colony-stimulating factor and ≤14 days prior to first dose of study drug for peg-filgrastim; ≥8 g/dL independent of transfusion support for ≤7 days prior to first dose of study drug; count ≥75 x 109 /L independent of transfusion support for ≤3 days prior to first dose of study drug
    2. Coagulation: (PT)/international normalized ratio (INR) \<1.5x the (ULN) and activated partial thromboplastin time (aPTT) \<1.5x ULN (unless the subject is receiving anticoagulant therapy and INR and partial PT/aPTT are within therapeutic range of intended use of anticoagulants)
    3. Liver function: total ≤1.5x ULN (≤3.0x ULN for subjects with Gilbert's syndrome), aminotransferase () and aspartate aminotransferase (AST) ≤3.0x ULN; except for subjects who have tumor infiltration of the liver, where ALT and AST ≤5x ULN
    4. Renal function: must have a ≥60 mL/min (via Cockcroft-Gault equation, institutional standard, or measured)
    5. Cardiac function: baseline interval using Fredericia's formula ≤470 ms (adolescents 12-17 years of age: ≤450 ms) and a ≥50% evaluated via echocardiogram or multi-gated acquisition (MUGA) scan
  8. Availability of sample or newly obtained core/excisional biopsy of a tumor not previously irradiated
  9. A female subject may be eligible to participate if she is not pregnant or planning a pregnancy, not breastfeeding, and following protocol mediated guidance to avoid pregnancy
  10. A male subject must have had a prior vasectomy and agree to use a condom during the treatment period and for at least 90 days after the last dose of study treatment
  11. A male subject must refrain from donating sperm while taking CFT8634 and for 90 days post-last dose
  12. A female subject must refrain from donating ova while taking CFT8634 and for 180 days after discontinuation
  13. All subjects must refrain from donating blood and blood products while receiving study drug and for 30 days post-last dose

Exclusion criteria

Exclusion Criteria:

  1. Subject has had major surgery within 21 days prior to the planned first dose of CFT8634

    a. Minor surgery (eg, minor of extracranial site, central venous catheter placement, shunt revision) is permitted within 21 days prior to first dose of CFT8634

  2. Subject has received standard of care or systemic anti-neoplastic therapy within 14 days or 5 half-lives, whichever is shorter, prior to the planned first dose of CFT8634
  3. Subject has received radiation therapy within 14 days prior to the planned first dose of CFT8634
  4. Prior treatment with BRD9 degrader
  5. Subject has central nervous system (CNS) involvement (primary tumor or disease), except in the following circumstances:

    1. Subjects with previously treated may be permitted to participate provided they are stable (without evidence of progression by imaging 14 days prior to the first dose of study drug and any neurologic symptoms have stabilized), have no evidence of new or enlarging brain metastases, and if they are taking , they are on stable or tapering doses for at least 7 days prior to first dose of study drug. Antiseizure therapy is permitted provided the medication is not otherwise excluded and seizures have been controlled for at least 28 days since the last antiseizure medication adjustment
    2. Subjects with asymptomatic brain metastases found on Screening magnetic resonance imaging (MRI) may be permitted to be entered into the study without prior radiation therapy to the brain if they do not require immediate surgical or radiation therapy in the opinion of the treating investigator and in the opinion of a radiation therapy or neurosurgical consultant
  6. Subject has any evidence of a CNS bleed including intra-tumoral hemorrhage
  7. Subject has known bleeding diathesis
  8. Subject has impaired cardiac function or cardiac disease (i.e. uncontrolled heart disease/hypertension, clinically significant arrythmias, unstable angina/myocardia infarction/stroke within 180 days prior to screening)
  9. Subject with presence of inflammatory vascular disease or microangiopathy (eg, thrombotic microangiopathies, hemolytic uremic syndrome [HUS], atypical HUS)
  10. Subject with known , other than study indication, that is progressing or has required treatment within the past 3 years

    a. Subject with basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or carcinoma in situ (i.e. breast carcinoma, cervical cancer in situ) that have undergone potentially curative therapy are not excluded

  11. Subject has received live, attenuated vaccine within 28 days prior to first dose administration
  12. Subject with known history of (HIV) infection
  13. Subject had a venous thrombosis within 14 days prior to first dose of study drug
  14. Subject with gastrointestinal absorption issues (e.g., malabsorption syndrome or other illness that could affect oral absorption).
  15. Concurrent administration of strong cytochrome P450 (CYP) 3A4 inhibitors and inducers, and multidrug resistance mutation 1 (MDR1) inhibitors.
Terms in these criteria, in plain language(24)

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.

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.

Histologically or cytologically confirmed

The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).

Your pathology report is the document that shows this.

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.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

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.

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.

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.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

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.

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

INR, PT and aPTT (clotting tests)

Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.

Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

Creatinine clearance (CrCl)

How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.

QT and QTc

On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.

The study may name a correction formula and a limit in milliseconds, often around 450–480.

LVEF (left ventricular ejection fraction)

The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.

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.

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.

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.

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.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

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.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
49 participants (actual)

Study arms

  • Experimental
    Dose Escalation Phase 1/Part1: CFT8634

    Up to approximately 40 subjects ≥18 years of age or between ≥16 and \<18 years of age and weighing ≥50 kg with locally advanced or metastatic SMARCB1-perturbed cancers, including synovial sarcoma and SMARCB1-null tumors, having received ≥ 1 prior anticancer therapy

    Drug: CFT8634

  • Experimental
    Dose Escalation Phase 1/Part 2: CFT8634

    Up to approximately 6-12 subjects ≥12 and \<16 years of age and weighing ≥40 kg or ≥16 and \<18 years of age and weighing ≥40 kg and \<50 kg with locally advanced or metastatic SMARCB1-perturbed cancers, including synovial sarcoma and SMARCB1-null tumors

    Drug: CFT8634

  • Experimental
    Phase 2 - Arm A: CFT8634

    Approximately 30 subjects with locally advanced or metastatic synovial sarcoma at the recommended phase 2 dose (RP2D) having received 1-2 prior anticancer therapies

    Drug: CFT8634

  • Experimental
    Phase 2 - Arm B: CFT8634

    Approximately 20 subjects with locally advanced or metastatic SMARCB1-null tumors at the RP2D having received ≥1 prior anticancer therapy

    Drug: CFT8634

Interventions

  • DrugCFT8634

    Oral dose of CFT8634

06

What researchers measure

Primary outcomes

  1. Frequency and severity of AEs and serious adverse events (SAEs)

    Phase 1 and Phase 2

    Time frame: From screening until at least 30 days after completion of study treatment

  2. Number of subjects with changes between baseline and post-baseline safety assessments based on safety laboratory results graded by CTCAE v5.0

    Phase 1 and Phase 2

    Time frame: From screening until at least 30 days after completion of study treatment

  3. Frequency of dose interruptions and dose reductions

    Phase 1 and Phase 2

    Time frame: From first dose until end of treatment

  4. Incidence of dose limiting toxicities (DLTs)

    Phase 1 only

    Time frame: From first dose until 28 days after first dose

  5. Overall Response Rate (ORR)

    Phase 2 only according to RECIST v1.1 criteria

    Time frame: Up to approximately 24 months

Secondary outcomes

  1. Plasma concentration of CFT8634 to characterize the pharmacokinetics (PK) parameters of CFT8634

    Plasma concentration of CFT8634 at the scheduled timepoints

    Time frame: At multiple time points up to approximately 24 weeks

  2. Asses dose proportionality assessment

    Dose proportionately assessment at the scheduled timepoints

    Time frame: At multiple time points up to approximately 24 weeks

  3. Assess the pharmacodynamics by percent reduction from baseline of target protein

    Tumor BRD9 degradation at scheduled timepoints

    Time frame: At multiple time points up to approximately 24 weeks

  4. ORR

    Phase 1 only according to RECIST v1.1 criteria

    Time frame: Up to approximately 24 months

  5. Duration of Response (DOR)

    DOR defined as time from first assessment of PR or CR to follow-on first assessment of progressive disease (PD)

    Time frame: Up to approximately 24 months

  6. Progression Free Survival (PFS)

    PFS defined as the time from first treatment received until PD is assessed

    Time frame: Up to approximately 24 months

  7. Overall Survival (OS)

    OS is defined as the time from first dose of study treatment to the date of death, irrespective of the cause of death. (Phase 2 only)

    Time frame: Up to approximately 48 months

  8. Time to next treatment

    Interval from the date of initiation of a treatment to the date of commencement of the next line of therapy

    Time frame: Up to approximately 8 months

07

Study locations

12 sites
  • City of Hope
    Duarte, California 91010, United States
  • Sarcoma Oncology Research Center
    Santa Monica, California 90403, United States
  • University of Colorado - Aurora Cancer Center
    Aurora, Colorado 80045, United States
  • Mayo Clinic - Jacksonville
    Jacksonville, Florida 32224, United States
  • University of Iowa Hospital and Clinics
    Iowa City, Iowa 52242, United States
  • Massachusetts General Hospital
    Boston, Massachusetts 02114, United States
  • Mayo Clinic - Rochester
    Rochester, Minnesota 55905, United States
  • Washington University School of Medicine
    Saint Louis, Missouri 63110, United States
  • David H. Koch Center for Cancer Care at Memorial Sloan Kettering Cancer Center
    New York, New York 10021, United States
  • Columbia University
    New York, New York 10027, United States
  • Cincinnati Children's Hospital Medical Center
    Cincinnati, Ohio 45229, United States
  • MD Anderson Cancer Center
    Houston, Texas 77030, United States
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 17, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05355753
Lead sponsor
C4 Therapeutics, Inc.
Responsible party
Sponsor
First posted
May 2, 2022
Start date
Mar 25, 2022
Primary completion
Dec 19, 2023
Completion
Dec 19, 2023
Last update
Dec 17, 2024

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is terminated, as verified in Dec 2024. You cannot join it, but the record below documents what was studied.

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