Endometrial Endometrioid AdenocarcinomaPhase 2NCT07436793

Progestins for the Treatment of Endometrial Cancer or Precancers of the Uterus Before Surgery, The Pro-Window Trial

A Phase 2 study testing Biopsy Procedure, Curettage Procedure and Hysterectomy in people with Endometrial Endometrioid Adenocarcinoma and Endometrial Hyperplasia, run by New Mexico Cancer Research Alliance at 4 sites in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts

Official record

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Trial summary

Who is it for?: Ages 18 years and older, women only
Conditions the study is for: Endometrial Endometrioid Adenocarcinoma, Endometrial Hyperplasia
What is being tested?: Biopsy Procedure, Curettage Procedure and Hysterectomy
Type of treatment: Surgery or procedure
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 140 participants
Where: 4 sitesUnited States
Study dates: 15 Jun 2026to 30 Jun 2031
Phase: Phase 2

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
Women only
No healthy volunteers
Adult, Older adult

Who may be able to join

Patients must have a histologically proven diagnosis of endometrioid endometrial adenocarcinoma by endometrial curettage or biopsy within 8 weeks prior to registration. Pathology reports should document adequate tissue from the biopsy and slides should be reasonable determined to be obtainable by the study team for study use
History/physical examination within 42 +/- 5 days of planned surgical procedure (18-21 days from day 1)
Age ≥ 18
The trial is open only to women with primary endometrioid adenocarcinoma of the uterine corpus (all histologic grades and stages) who are planned and appropriate for primary surgical treatment to include removal of the uterine corpus via any surgical modality. The patient must be considered a suitable surgical candidate
Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, 2, or 3 within 28 days prior to registration
Formalin-fixed, paraffin-embedded tumor tissue from the biopsy or curettage must be reasonably deemed available for submission along with the corresponding pathology report

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Platelets ≥ 100,000/μl
Granulocytes (absolute neutrophil count [ANC]) ≥ 1,500/μl
Creatinine ≤ 1.6 mg/dl
Serum glutamic-pyruvic transaminase (SGPT) (alanine transaminase [ALT]) ≤ 3 x upper limits of normal
Bilirubin within institutional normal limits
The patient must provide study-specific informed consent and authorization permitting release of personal health information prior to study entry
Any patients of childbearing potential must have a negative pregnancy test

Who cannot join

Patients with any non-endometrioid histology (such as serous, clear cell, or carcinosarcoma or mixed)
Patients who have received prior progestin or anti-estrogen therapy during the 3 months before the diagnosis of endometrioid adenocarcinoma of the uterine corpus is established. Estrogen therapy alone is allowed
Patients with ECOG performance status of 4
Patients with history of deep venous thrombosis or pulmonary embolism within the past 2 years or ongoing thromboembolic disorders
Patients who have previously received systemic, radiation or other treatment for uterine cancer
Patients for whom formalin-fixed, paraffin-embedded tumor tissue from the biopsy or curettage is scant or unavailable
Patients with a suspected or known peanut allergy
Patients with serious comorbidities or gastrointestinal obstruction that precludes taking oral medications or have malabsorptive disease

Trial locations and contacts

4 sites in 1 country. Contact the study team or a site near you to ask about taking part.

United States4 sites, 4 recruiting

University of New Mexico Cancer Center
Albuquerque, New Mexico, 87106
Carolyn Y. Muller, 505-925-0461, cmuller@salud.unm.edu
Carolyn Y. Muller
Recruiting
University of Virginia Cancer Center
Charlottesville, Virginia, 22908
Linda R. Duska, lrd5d@virginia.edu
Linda R. Duska
Not yet recruiting
University of Iowa/Holden Comprehensive Cancer Center
Iowa City, Iowa, 52242
Megan E. McDonald, 319-356-2015, megan-e-mcdonald@uiowa.edu
Megan E. McDonald
Recruiting
University of Utah Sugarhouse Health Center
Salt Lake City, Utah, 84106
Kathryn Maurer, kathryn.maurer@hsc.utah.edu
Kathryn Maurer
Not yet recruiting

Other trials in United States

About this study

Official title: Evaluating Promising Progestins in Endometrial Cancer Through a Rotating Umbrella Surgical Window Trial - The PRO-WINDOW TRIAL for Endometrial Cancer

This phase II trial tests compares the effect of progestins, megestrol acetate to micronized progesterone, in treating patients with endometrial cancer and precancers of the uterus (atypical endometrial hyperplasia) before surgery. Progestins, similar to the natural hormone progesterone, are approved drugs used in birth control and hormone replacement pills, and some can treat uterine endometrial cancers. In the initial comparison of this rotating umbrella trial, megestrol acetate, a progestin, will be compared to micronized progesterone, a form of natural progesterone that is a hormone produced by body normally. Hormone therapy using megestrol acetate and micronized progesterone may be effective in treating patients with endometrial cancer or atypical endometrial hyperplasia before surgery, and understanding the tissue effects of each agent on the malignant endometrium will uncover novel mechanistic and biomarker data to understand how best to advanced hormone therapy for endometrial cancer.

Read the detailed description

PRIMARY OBJECTIVES:

Perform an adaptive, master protocol, surgical window of opportunity rotating umbrella trial to assess the effectiveness of progestins in tissues from women with newly diagnosed endometrial cancer or atypical endometrial hyperplasia.

II. Establish biomarkers and molecular signatures of progestin efficacy in patients with endometrial cancer.

OUTLINE: Patients are randomized to 1 of 2 arms in the initial comparison.

ARM I: Patients undergo biopsy or curettage and then receive megestrol acetate orally (PO) twice daily (BID) 21-24 days prior to standard of care (SOC) hysterectomy on study.

ARM II: Patients undergo biopsy or curettage and then receive micronized progesterone PO once daily (QD) beginning 21-24 days prior to SOC hysterectomy on study.

After completion of study treatment, patients are followed up at 30-45 days after surgery.

Conditions: Endometrial Endometrioid Adenocarcinoma, Endometrial Hyperplasia
Being tested: Biopsy Procedure, Curettage Procedure, Hysterectomy, Megestrol Acetate, Progesterone Only Hormone Replacement Therapy
Medical subject headings: Endometrial Hyperplasia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Biopsy ProcedureProcedure or surgery
Also called Biopsy, BIOPSY_TYPE, Bx
Undergo biopsy
Curettage ProcedureProcedure or surgery
Also called Curettage
Undergo curettage
HysterectomyProcedure or surgery
Also called Hysterectomy NOS, hysterectomy type, hysterectomy_type
Undergo hysterectomy
Megestrol AcetateDrug
Also called 17-Hydroxy-6-methylpregna-4,6-diene-3,20-dione acetate, 17.alpha.-Acetoxy-6-methylpregna-4,6-diene-3,20-dione, 6-Dehydro-6-methyl-17.alpha.-acetoxyprogesterone, 6-Methyl-6-dehydro-17.alpha.-acetoxyprogesterone
Given PO
Progesterone Only Hormone Replacement TherapyDrug
Also called Progesterone only
Given PO

Study groups in NCT07436793
Study group	Role	What they receive
Arm I (biopsy, curettage, MPA, hysterectomy)	Active comparator	Patients undergo biopsy or curettage and then receive megestrol acetate PO BID 21-24 days prior to SOC hysterectomy on study. Receives: Procedure: Biopsy Procedure; Procedure: Curettage Procedure; Procedure: Hysterectomy; Drug: Megestrol Acetate
Arm II (biopsy, curettage, progesterone, hysterectomy)	Experimental	Patients undergo biopsy or curettage and then receive micronized progesterone PO QD beginning 21-24 days prior to SOC hysterectomy on study. Receives: Procedure: Biopsy Procedure; Procedure: Curettage Procedure; Procedure: Hysterectomy; Drug: Progesterone Only Hormone Replacement Therapy

What is being measured

The primary outcome is the main question the study is designed to answer.

Tissue response to progestin therapy
Will be determined by a change in the percentage in the expression of the proliferative marker Ki-67 comparing the pretreatment diagnostic biopsy to the posttreatment hysterectomy specimen. Immunohistochemical evaluation of Ki-67 protein expression will be determined as a continuous variable using the percent of cells staining positive in the nucleus
Measured: From the time of pre treatment diagnostic biopsy to the time of post treatment hysterectomy specimen

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

15 Jun 202630 Jun 2031

First posted27 Feb 2026
Study start15 Jun 2026
Primary completion30 Jun 2030 (estimated)
Study completion30 Jun 2031 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Endometrial Endometrioid AdenocarcinomaStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: None (open label)
Enrolment: 140 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07436793
Sponsor's protocol ID: INST UNM 2502 PRO-WINDOW
Other IDs: NCI-2025-06611, INST UNM 2502 PRO-WINDOW, P01CA278735, P30CA118100
Status last verified: Jun 2026
First submitted: 20 Feb 2026
Last updated: 2 Jul 2026
Results posted: No
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

Interested in taking part?

Each site lists its own contact. Pick the site nearest to you.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See sites and contacts

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Endometrial Adenocarcinoma, Endometrial Clear Cell Adenocarcinoma
RecruitingPhase 1
Testing Different Amounts of the Combination of Drugs M1774 and ZEN-3694 for the Treatment of Recurrent Ovarian and Endometrial Cancer
Recurrent Endometrial Carcinoma, Recurrent Endometrial Clear Cell Adenocarcinoma

All Endometrial Endometrioid Adenocarcinoma trials