ClinicalTrials.gg
RecruitingNCT05997017Updated Nov 13, 2025

Trial of Nab-Sirolimus in Combination With Letrozole in Patients With Advanced or Recurrent Endometrioid Endometrial Cancer

A Phase 2 interventional study of nab-sirolimus in Endometrial Cancer, Endometrioid Tumor and Cancer, sponsored by Aadi Bioscience, Inc.. Recruiting at 9 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-11-13.

Sponsored by Aadi Bioscience, Inc. · Phase 2, Interventional, and Treatment

From the registry’s dates

  • Started Dec 2023; still recruiting 2 years 10 months later.
Phase
Phase 2
Study type
Interventional
Enrollment
29
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

A Phase 2 Multi-center Open-label Trial of nab-Sirolimus in Combination with Letrozole in Advanced or Recurrent Endometrioid Endometrial Cancer

Read the detailed description

This is a prospective phase 2, open-label, multi-institutional study to evaluate the efficacy and safety of nab-sirolimus + letrozole in patients with advanced or recurrent endometrioid endometrial carcinoma who have received 0-1 prior lines of chemotherapy in the recurrent/metastatic setting. Patients will be treated with nab-sirolimus (given IV on Days 1 and 8 in a 21-day cycle, combined with letrozole (orally, daily) until unacceptable toxicity or disease progression, or until in the opinion of the Investigator the patient is no longer benefiting from therapy, or at patient discretion.

02

Conditions studied

  • Endometrial Cancer
  • Endometrioid Tumor
  • Cancer
  • Tumor
  • Recurrent Endometrial Carcinoma
  • Endometrioid Endometrial Cancer

Keywords

  • nab-Sirolimus
  • FYARRO
  • Letrozole
  • Endometrial
  • Recurrent
  • ABI-009
  • Endometrial Carcinoma
  • Endometrioid Tumor
  • Endometrial Cancer
  • Recurrent Endometrial Carcinoma
  • Endometrioid Endometrial Cancer
03

In context

Endometrial Neoplasms

1,425 studies on the registry are indexed under Endometrial Neoplasms; 473 are open to participants now.

This study's planned enrollment of 29 is below the median of 71 across 1,026 interventional studies indexed under Endometrial Neoplasms.

Browse Endometrial Neoplasms studies →

Lead sponsor

Aadi Bioscience, Inc. is the lead sponsor of 11 studies on the registry; 1 is open to participants now.

Of its 7 completed or terminated interventional studies of FDA-regulated products, 6 (86%) have results posted.

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

04

Who can participate

Ages eligible
18 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. Patients must have clinically confirmed advanced or recurrent endometrioid endometrial carcinoma. Histologic documentation of the recurrence is suggested but not required.
  2. All patients must have 1 or more measurable target lesion at baseline by computed tomography (CT; or magnetic resonance imaging [MRI] if CT scans are ) as defined by version 1.1.
  3. Patients must have EEC that is or locally advanced where surgical resection is not an option or likely to result in severe morbidity.
  4. Prior treatment history:

    1. setting - treatment with chemotherapy, hormonal therapy,, and/or other therapy is permitted as long as theadjuvant therapy ended ≥6 months from enrollment.
    2. Recurrent/advanced/metastatic setting - treatment with 0-1 prior chemotherapy regimens is permitted (patients may be naïve to chemotherapy); chemotherapy must have been completed ≥3 months prior to enrollment. Patients are permitted to have received adjuvant chemotherapy and no more than 1 in the recurrent/advanced/metastatic setting.
    3. Non-chemotherapy-based treatment (eg, checkpoint inhibitors, hormonal therapy, and/or small molecule agents) is permitted at any point as long as therapy ended ≥4 weeks prior to enrollment.
    4. Patients who have received prior therapy in the recurrent/advanced/metastatic setting must have achieved a complete or partial response(investigator-assessed) to at least 1 therapy.
  5. Age: 18 years or older.
  6. Patient must have (ECOG) performance status of 0 or 1.
  7. Adequate liver function:

    1. Total ≤1.5 × (ULN) (unless due to Gilbert's syndrome, then ≤3 × ULN)
    2. (AST) ≤2.5 × ULN (≤5 × ULN if attributable to liver metastases)
  8. Adequate renal function: (CrCL) ≥30 mL/min based on Cockcroft-Gault
  9. Adequate hematologic parameters:

    1. (ANC) ≥1.0 × 109/L (growth factor support allowed)
    2. count ≥100,000/mm3 (100 × 109/L) (transfusion and/or growth factor support allowed)
    3. ≥8.0 g/dL (transfusion and/or growth factor support allowed)
  10. Fasting serum triglyceride must be ≤300 mg/dL; fasting serum cholesterol must be less than or equal to 350 mg/dL.
  11. Minimum of 4 weeks since any major surgery, completion of radiation, or completion of prior systemic anticancer therapy, or at least 5 half-lives if the prior therapy is a single agent small-molecule therapeutic, and adequately recovered from the acute toxicities of any prior therapy, including neuropathy, to Grade ≤1.
  12. Non-pregnant and non-breastfeeding female:

    1. Females of must agree to use effective or abstinence without interruption from 28 days prior to starting nab-Sirolimus through 3 months after the last dose of nab-Sirolimus and have a negative serum pregnancy test (beta human chorionic gonadotropin [β-hCG]) result at screening and agree to ongoing pregnancy testing during the course of the study, and after the end of study treatment. A second form of birth control is required even if she has had a tubal ligation.
    2. Sexual abstinence is considered a highly effective contraceptive method only if defined as refraining from heterosexual intercourse from 28 days prior to starting study medication throughout 3 months after last dose of study medication. The reliability of sexual abstinence should be evaluated in relation to the duration of the study and the preferred and usual lifestyle of the patient.
  13. The patient understands and signs the .
  14. Willingness and ability to comply with scheduled visits, laboratory tests, and other study procedures.
  15. Patients with a known history of (HIV)infection are eligible if:

    1. There has been no acquired immunodeficiency syndrome (AIDS)-defining opportunistic infection in 12 months prior to enrollment.
    2. The patient has been receiving an antiretroviral therapy regimen for≥4 weeks and the HIV viral load is \<400 copies/mL prior to enrollment.
    3. Antiretroviral therapy regimen does not include strong cytochrome(CYP)3A4 inhibitors or inducers

Exclusion criteria

Exclusion Criteria:

  1. Prior treatment with an mTOR inhibitor, including nab-sirolimus.
  2. Patients with known inactivating TSC1 or TSC2 alterations (based on tissue or liquid next generation sequencing [NGS]) unless the PRECISION 1 study (NCT05103358) has been closed to enrollment.
  3. Severe (Grade ≥3) ongoing infection requiring parenteral or oral anti-infective treatment, either ongoing or completed ≤7 days prior to enrollment.
  4. Patients with primary disease (ie, those who have never achieved a complete or partial response to prior therapy) are not permitted on study.
  5. Patients with the following are excluded:

    1. Known or suspected .
    2. Severe heart disease defined as unstable angina pectoris, (NYHA) Class III or IV congestive heart failure, myocardial infarction ≤6 months prior to first study treatment, serious uncontrolled cardiac arrhythmia or any other cardiac disease.
    3. Severe lung disease defined as a diffusing capacity for carbon monoxide (DLCO) that is ≤50% of normal predicted value and/or an O2 saturation ≤88% at rest on room air (Note: spirometry and pulmonary function tests [PFTs] are not required to be performed unless clinically indicated).
    4. Nonmalignant medical illnesses that are uncontrolled or whose control may be jeopardized by the treatment with the study therapy.
    5. A history of other than the one under treatment unless the patient is disease-free for more than 5 years from completion of therapy administered with curative intent. Controlled non-melanoma skin cancers, carcinoma in situ of the cervix, resected incidental prostate cancer, certain low grade hematologic malignancies (eg, chronic lymphocytic leukemia [CLL], follicular lymphoma, etc), or other adequately treated carcinoma in situ may be eligible, after discussion with the Medical Monitor.
    6. Uncontrolled hypertension (systolic blood pressure ≥160 mmHg and/or diastolic blood pressure ≥100 mmHg
    7. Patients with history of interstitial lung disease and/or pneumonitis, or pulmonary hypertension.
    8. Active and/or infection and detectable viral load despite antiviral therapy
  6. Required use of concomitant medications with strong interactions (induction or inhibition) should be discontinued (strong inhibitors include ketoconazole, itraconazole, voriconazole, erythromycin, clarithromycin, telithromycin; strong inducers include rifampin and rifabutin). These agents must be discontinued prior to first dose of nab-sirolimus.
Terms in these criteria, in plain language(26)

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.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

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.

Metastases

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

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.

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.

Line of therapy

A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.

“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.

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.

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.

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.

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).

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.

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.

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.

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.

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.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

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.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

CYP3A (CYP3A4) inhibitors and inducers

CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.

Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
29 participants (estimated)

Study arms

  • Experimental
    Endometrioid Endometrial Cancer

    Patients with advanced or recurrent endometrioid endometrial carcinoma

    Drug: nab-sirolimus

Interventions

  • Prospective Phase 2, open-label, multi-institutional study to evaluate the efficacy and safety of nab-sirolimus + letrozole in patients

    Also known as: ABI-009

06

What researchers measure

Primary outcomes

  1. Overall response rate (ORR)

    ORR, defined as the proportion of patients with best overall response (BOR) of confirmed partial response (PR) or complete response (CR) from the time of study treatment initiation until progression of disease (PD) as determined by the Investigator using RECIST v1.1.

    Time frame: 12 Months

Secondary outcomes

  1. Duration of response (DOR)

    Determined for patients with BOR of confirmed CR or PR

    Time frame: 12 Months

  2. Disease Control Rate (DCR): CR or PR

    BOR of confirmed CR or PR (either of any duration) or stable disease (SD) following study treatment initiation (by IRR)

    Time frame: 12 Months

  3. Time to response (TTR)

    Time from study treatment initiation to initial measurement of CR or PR, where CR or PR is subsequently confirmed

    Time frame: 12 Months

  4. Progression-free survival (PFS)

    Number of months from study treatment initiation to the date of disease progression 3 or death due to any cause

    Time frame: 12 Months

  5. Overall survival (OS)

    Number of months from study treatment initiation to the date of death due to any cause or last follow up date if alive

    Time frame: 24 Months

  6. Incidence and severity

    Of treatment-emergent and treatment-related adverse events as assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE)

    Time frame: 12 Months

07

Study locations

9 of 9 sites recruiting
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Dec 2023 (actual). Primary completion is estimated for Dec 2026, 36 months after the start.

Of 139 phase 2 interventional studies under Endometrial Neoplasms, half reached primary completion within 55 months of starting (the median), counting those still running; a quarter within 37 and three quarters within 115. This study's planned 36 months is below that.

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

Registered
Aug 10, 2023
First posted
Aug 18, 2023
StartActual
Dec 28, 2023
Primary completionEst.
Dec 2026
CompletionEst.
Jun 2027
Last update
Nov 13, 2025
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 Nov 13, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT05997017
Lead sponsor
Aadi Bioscience, Inc.
Responsible party
Sponsor
First posted
Aug 18, 2023
Start date
Dec 28, 2023
Primary completion
Dec 2026 (estimated)
Completion
Jun 2027 (estimated)
Last update
Nov 13, 2025

Study contacts

Aadi Bioscience Medical Information
Contact
MedInfo@aadibio.com
1-888-246-2234
Willis Navarro, MD
study director · Aadi Bioscience

Oversight

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

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