ClinicalTrials.gg
TerminatedNCT05712694Updated Jun 25, 2026

Study of ADI-PEG 20 or Placebo Plus Gem and Doc in Previously Treated Subjects With Leiomyosarcoma (ARGSARC)

A Phase 3 interventional study of ADI PEG20 and Placebo in Soft Tissue Sarcoma, sponsored by Polaris Group. Terminated at 30 sites in 3 countries. Open to participants aged 18 Years to 99 Years. Per ClinicalTrials.gov, last updated 2026-06-25.

Primary conditionLeiomyosarcomaRegistry: SarcomaReclassifiedWhy we changed it
Registry
Sarcoma — the first condition term the registry derived for this study.
ClinicalTrials.gg
Leiomyosarcoma
Why
  1. The study's title name Leiomyosarcoma, a narrower term within Sarcoma.
Confidence
High: the new condition is named in the study's own title. Of 46 hand-checked studies reclassified this way, 72% were exactly right and 89% in the right disease family; the registry's first term was right for 4% (measured 2026-10-21). How we classify →
Wrong?
Tell us the study's main condition →

Sponsored by Polaris Group · Phase 3, Interventional, and Treatment

Why this study was terminated
Lack of Efficacy, no safety concern.
Phase
Phase 3
Study type
Interventional
Enrollment
218
Allocation
Randomized
Ages
18 Years to 99 Years
Sex
All
01

Study summary

To compare the efficacy and safety in subjects with advanced or metastatic LMS previously treated with an anthracycline.

Read the detailed description

This is a global, multicenter, randomized, double-blind, placebo-controlled, parallel-group phase 3 trial that will compare the efficacy and safety in subjects with advanced or metastatic LMS previously treated with an anthracycline.

02

Conditions studied

  • Soft Tissue Sarcoma

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Keywords

  • Soft Tissue Sarcoma
  • Arginine
  • Arginine Deiminase
  • ADI-PEG 20
  • Pegargiminase
  • Leiomyosarcoma
03

In context

Leiomyosarcoma Reclassified

177 studies on the registry are indexed under Leiomyosarcoma; 35 are open to participants now.

This study's enrollment of 218 is above the median of 54 across 151 interventional studies indexed under Leiomyosarcoma.

Browse Leiomyosarcoma studies →

Lead sponsor

Polaris Group is the lead sponsor of 20 studies on the registry; 2 are open to participants now.

Compared within Leiomyosarcoma, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Sarcoma. The counts are of registry records indexed under each term, refreshed daily. How we classify →

04

Who can participate

Ages eligible
18 Years to 99 Years
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

  • A subject will be eligible for study participation if he/she meets the following criteria:

    1. or cytologically confirmed, grade 2 or 3, LMS STS that would be standardly treated with Gem or GemDoc.
    2. Determination of LMS subtype: uterine or non-uterine.
    3. per 1.1 (Appendix A), defined as lesions that can be accurately measured in at least one dimension (longest diameter to be recorded) as ≥ 10 mm with CT scan, as ≥ 20 mm by chest x-ray, or ≥ 10 mm with calipers by clinical exam.
    4. Previous treatment with up to 2 systemic regimens, including at least 1 systemic regimen containing doxorubicin.
    5. Treatment > one year ago in the /neoadjuvant setting with Gem or Doc is allowed.
    6. Age >18 years.
    7. (ECOG) performance status of \< 1 at enrollment (Appendix B).
    8. Leukocytes ≥ 3,000/mcL.
    9. ≥ 1,500/mcL.
    10. ≥ 100,000/mcL.
    11. ≥ 8.0 g/dL
    12. Total ≤ 2 x . (≤ 3 x ULN for potential subjects with Gilbert's Disease)
    13. (SGOT)/ALT(SGPT) ≤ 3 x ULN (or ≤ 5 x ULN if liver are present)
    14. ≥ 60 mL/min (by Cockcroft-Gault equation).
    15. Serum uric acid ≤ 8 mg/dL (with or without medication control).
    16. range from 350 to 450 ms for adult men and from 360 to 460 ms for adult women.
    17. Subjects and their partners must be asked to use appropriate . They must agree to use 2 forms of contraception or agree to refrain from intercourse for the duration of the study and for 35 days after the last dose of ADI-PEG 20 or for at least 3 months (male subjects) or 6 months (female subjects) after treatment with gemcitabine, whichever is the longer duration.
    18. Ability to understand and willingness to sign the form.
    19. No concurrent drug studies are allowed.

Exclusion criteria

Exclusion Criteria:

  • A subject will not be eligible for study participation if he/she meets any of the exclusion criteria:

    1. Subjects with history of another primary cancer, including co-existent second , with the exception of: a) curatively resected non-melanoma skin cancer; b) curatively treated cervical carcinoma in situ; or c) other primary solid tumor with no known active disease present in the opinion of the Investigator will not affect subject outcome in the setting of current diagnosis.
    2. Currently receiving chemotherapy, immunotherapy, interferon, radiation therapy or other agents. Note: Chemotherapy agent is 5 half-lives prior to randomization. Radiation washout period is 7 days prior to randomization.
    3. Prior treatment with ADI-PEG 20, Gem or Doc. Patients treated > one year ago in the /neoadjuvant setting with Gem or Doc are allowed to be enrolled.
    4. Prior pelvic radiation.
    5. Known . Such patients must be excluded from this trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events.
    6. History of allergic reactions attributed to compounds of similar chemical or biologic composition to ADI-PEG 20, Gem, Doc, polysorbate 80, pegylated compounds, or other agents used in this study.
    7. Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
    8. History of seizure disorder not related to underlying cancer.
    9. Grade 2 or higher neuropathy.
    10. Pregnant and/or breastfeeding. Women of must have a negative pregnancy test within 14 days of study entry.
    11. Known -positivity. Because of the potential for pharmacokinetic interactions of antiretroviral therapy with the study treatment. In addition, these patients are at increased risk of lethal infections when treated with marrow-suppressive therapy. Appropriate studies will be undertaken in patients receiving combination antiretroviral therapy when indicated.
    12. Currently receiving other agents.
    13. Subjects under guardianship, curatorship, under legal protection or deprived of liberty by an administrative or judicial decision
Terms in these criteria, in plain language(23)

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.

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.

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.

Adjuvant and neoadjuvant

Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.

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.

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.

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).

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.

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.

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.

Metastases

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

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.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

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.

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.

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.

Washout period

A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.

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.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

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.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Care provider, Investigator)
Enrollment
218 participants (actual)

Study arms

  • Experimental
    ADIGemDoc

    ADI-PEG 20: 36 mg/m2 on Day -7 of Cycle 1, and Days 1, 8, and 15 of each 21-day cycle Gemcitabine: 600 mg/m2 on days 1 and 8 of each 21-day cycle Docetaxel: 60 mg/m2 on day 8 of each 21-day cycle

    Drug: ADI PEG20

  • Placebo comparator
    PBOGemDoc

    Placebo: matched PBO on Day -7 of Cycle 1, and Days 1, 8, and 15 of each 21-day cycle Gemcitabine: 900 mg/m2 on days 1 and 8 of each 21-day cycle Docetaxel: 75 mg/m2 on day 8 of each 21-day cycle

    Other: Placebo

Interventions

  • Treatment for advanced or metastatic uterine/non-uterine leiomyosarcoma (LMS)

    Also known as: Pegargiminase

  • OtherPlacebo

    Treatment for advanced or metastatic uterine/non-uterine leiomyosarcoma (LMS)

06

What researchers measure

Primary outcomes

  1. Primary End Point of PFS

    The primary objective is to compare the primary endpoint of PFS in subjects treated with the arginine degrading enzyme ADI-PEG 20 plus Gem and Doc (ADIGemDoc) or PBO plus Gem and Doc (PBOGemDoc) in the 2nd or 3rd line setting using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 assessed by blinded independent central review committee (BICR)

    Time frame: Subjects will receive triplet combination treatment followed by weekly monotherapy ADI-PEG 20 or PBO (Each cycle is 21 days). Subjects tolerating chemotherapy may continue chemotherapy beyond 8 cycles and up to 104 weeks (~2 years).

Secondary outcomes

  1. Secondary End Point of ORR (CR+PR)

    The secondary objectives are to compare ADIGemDoc versus PBOGemDoc with respect to: Objective response rate (ORR) (complete response \[CR\] + partial response \[PR\]) The secondary endpoint of ORR will be assessed by BICR using RECIST 1.1 and tested using a CMH test stratified by the stratification factors used during the randomization based on the ITT population.

    Time frame: Subjects will receive triplet combination treatment followed by weekly monotherapy ADI-PEG 20 or PBO (Each cycle is 21 days). Subjects tolerating chemotherapy may continue chemotherapy beyond 8 cycles and up to 104 weeks (~2 years).

  2. Secondary End Point of Overall Survival (OS)

    The secondary objectives are to compare ADIGemDoc versus PBOGemDoc with respect to: OS The secondary endpoint of OS will be tested using a log-rank test stratified by the stratification factors used during the randomization based on the ITT population. A stratified Cox model will be used to estimate HR and 95% CI, and KM curves will be used to estimate OS median and 95% CI.

    Time frame: Subjects will receive triplet combination treatment followed by weekly monotherapy ADI-PEG 20 or PBO (Each cycle is 21 days). Subjects tolerating chemotherapy may continue chemotherapy beyond 8 cycles and up to 104 weeks (~2 years).

  3. Secondary End Point of Safety and Tolerability

    All clinically significant abnormalities and deteriorations will be followed and graded according to the National Cancer Institute Common Terminology Criteria for Adverse Event (NCI CTCAE V5).

    Time frame: Subjects will receive triplet combination treatment followed by weekly monotherapy ADI-PEG 20 or PBO (Each cycle is 21 days). Subjects tolerating chemotherapy may continue chemotherapy beyond 8 cycles and up to 104 weeks (~2 years).

07

Study locations

30 sites
  • Mayo Clinic Arizona
    Phoenix, Arizona 85054, United States
  • USC Norris comprehensive cancer center
    Los Angeles, California 90033, United States
  • Stanford University Medical Centre
    Palo Alto, California 94304, United States
  • UCSF
    San Francisco, California 94158, United States
  • UCLA
    Santa Monica, California 90404, United States
  • University of Colorado Cancer Center/ CU Anschutz Medical Campus
    Aurora, Colorado 80045, United States
  • Mayo Clinic Florida
    Jacksonville, Florida 32224, United States
  • University of Miami/ Sylvester Comprehensive Cancer Center
    Miami, Florida 33136, United States
  • Moffitt Cancer Center
    Tampa, Florida 33612, United States
  • Northwestern
    Chicago, Illinois 60611, United States
  • Indiana University
    Indianapolis, Indiana 46202, United States
  • University of Iowa
    Iowa City, Iowa 52242, United States
  • Mass General Brigham Cancer Center
    Boston, Massachusetts 02114, United States
  • University of Michigan
    Ann Arbor, Michigan 48109, United States
  • Mayo Clinic Rochester
    Rochester, Minnesota 55905, United States
  • Washington University School of Medicine - Siteman Cancer Center
    St Louis, Missouri 63110, United States
  • NYU Langone Health
    New York, New York 10016, United States
  • Memorial Sloan Kettering Cancer Center
    New York, New York 10065, United States
  • Duke Cancer Institute
    Durham, North Carolina 27710, United States
  • University Hospitals Cleveland Medical Center
    Cleveland, Ohio 44106, United States
  • Ohio State University Wexner Medical Center/ The James Cancer Hospital and Solove Research Institute
    Columbus, Ohio 43210, United States
  • UPenn (Abramson Cancer Center, Pennsylvania Hospital)
    Philadelphia, Pennsylvania 19106, United States
  • UPMC Hillman Cancer Center
    Pittsburgh, Pennsylvania 15232, United States
  • University of Texas MD Anderson Cancer Center
    Houston, Texas 77030, United States
  • Medical College of Wisconsin/ Froedtert Hospital
    Milwaukee, Wisconsin 53226, United States
  • UHN - Princess Margaret Cancer Center (Ontario)
    Toronto, Ontario M5G 2M9, Canada
  • McGill University Health Centre (Quebec)
    Montreal, Quebec H4A 311, Canada
  • Chang Gung Medical Foundation Kaohsiung
    Kaohsiung City, Niaosong District 83301, Taiwan
  • National Taiwan University Hospital
    Taipei, Taipei 10002, Taiwan
  • Taipei Veterans General Hospital
    Taipei, Taipei 11217, Taiwan
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Nov 2023 to primary completion in May 2026, 29 months.

How these figures are worked out, and which studies are left out of them.

Registered
Dec 13, 2022
First posted
Feb 3, 2023
StartActual
Nov 29, 2023
Primary completionActual
May 25, 2026
CompletionActual
May 25, 2026
Last update
Jun 25, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jun 25, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT05712694
Lead sponsor
Polaris Group
Responsible party
Sponsor
First posted
Feb 3, 2023
Start date
Nov 29, 2023
Primary completion
May 25, 2026
Completion
May 25, 2026
Last update
Jun 25, 2026

Study contacts

John S Bomalaski
study director · Polaris Group

Oversight

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

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This study is terminated, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.

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Studies of the drug tested here: Pegargiminase

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