EndometriosisPAINLESSNCT07652593
Interaction Between Decidual Cells and NK Cells in Endometriosis
A study testing Biological Sample Collection in people with Endometriosis, run by Hopital Foch at 1 site in France.
Trial summary
Endometriosis is a chronic gynecological disease characterized by the presence of endometrial-like tissue outside the uterus and is frequently associated with pelvic pain and infertility. Increasing evidence suggests that immune dysfunction may contribute to the development and persistence of the disease. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Endometriosis
- What is being tested?
- Biological Sample Collection
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteFrance
- Study dates
- Jun 2026to Oct 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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
- Endometriosis Group
- Female participant aged 18 years or older.
- Confirmed diagnosis of deep endometriosis by imaging or surgery.
- Pelvic pain and/or severe dysmenorrhea (Visual Analog Scale > 4).
- Premenopausal.
- No contraceptive or hormonal treatment during the study menstrual cycle.
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- Affiliated with a health insurance system.
- Able and willing to provide written informed consent.
- Control Group
- Female participant aged 18 years or older.
- No diagnosis of endometriosis.
- Premenopausal.
- No contraceptive or hormonal treatment during the study menstrual cycle.
- No chronic pelvic pain or severe dysmenorrhea (Visual Analog Scale < 4).
- Affiliated with a health insurance system.
- Able and willing to provide written informed consent.
Who cannot join
- Current infection.
- Active cancer.
- Active autoimmune disease.
- Concomitant hormonal treatment.
- Pregnancy.
- Participant under guardianship or legal protection.
- Participant deprived of liberty.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
France1 site
Hôpital Foch
Suresnes, 92150
Florence COUPPEY, Clinical project manager, +33(0)1 46 25 31 30, f.couppey@hopital-foch.com
About this study
Official title: Interaction Between Decidual Cells and Natural Killer Cells in Endometriosis: A Prospective Pilot Case-Control Study
Endometriosis is a chronic gynecological disease characterized by the presence of endometrial-like tissue outside the uterus and is frequently associated with pelvic pain and infertility. Increasing evidence suggests that immune dysfunction may contribute to the development and persistence of the disease.
The purpose of this prospective case-control study is to compare immune cell characteristics in women with deep endometriosis and women without endometriosis during the secretory phase of the menstrual cycle. Participants will undergo collection of clinical data, blood samples, endometrial samples, and vaginal microbiota samples. For participants undergoing clinically indicated pelvic surgery, additional biological samples may be collected during the procedure. The study aims to improve understanding of the immune mechanisms involved in endometriosis and to identify potential biomarkers associated with the disease.
Read the detailed description
Endometriosis affects approximately 10-15% of women of reproductive age and represents a major public health concern. Despite its high prevalence, the pathophysiological mechanisms underlying the disease remain incompletely understood. Increasing evidence suggests that alterations in the immune environment of the endometrium may contribute to the establishment and progression of endometriosis. In particular, uterine immune cells may play a role in regulating local inflammation and tissue homeostasis. Characterizing these immune mechanisms may improve understanding of disease development and identify potential biomarkers associated with endometriosis.
PAINLESS is a prospective, single-center, pilot case-control study conducted at Foch Hospital (Suresnes, France). The study will enroll 50 adult women, including 25 participants with confirmed deep endometriosis and 25 control participants without endometriosis.
Biological samples will be collected during the secretory phase of the menstrual cycle (days 16-24). Depending on clinical management, study procedures may include:
- Collection of demographic and clinical data
- Assessment of symptoms and quality of life
- Blood sampling
- Endometrial sampling
- Vaginal microbiota sampling
- Collection of additional biological specimens during clinically indicated pelvic surgery.
Biological samples will be analyzed to characterize immune cell populations, evaluate soluble immune mediators, investigate associations with hormonal and clinical parameters, and explore biological mechanisms involved in endometriosis.The primary objective is to compare the expression of immune-related markers in endometrial and peritoneal samples obtained from women with endometriosis and controls. Secondary objectives include characterization of immune cell phenotypes and functions, evaluation of immune-related soluble factors, investigation of interactions between immune and endometrial cells, assessment of correlations with hormonal and clinical data, exploratory genetic analyses, and creation of a vaginal microbiota biobank. Results from this pilot study are expected to provide preliminary data for future research aimed at improving the understanding, diagnosis, and management of endometriosis.
- Conditions
- Endometriosis
- Being tested
- Biological Sample Collection
- Keywords
- Endometriosis, Deep Endometriosis, Natural Killer Cells, NK Cells, Endometrial Immune Microenvironment, CD39, Immunology, Vaginal Microbiota, Pelvic Pain, Cytokines, Women's Health, Biomarkers
- Medical subject headings
- Endometriosis, Pelvic Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Biological Sample CollectionProcedure or surgery
Collection of blood samples, endometrial samples, vaginal microbiota samples, and surgical specimens when clinically indicated for immunological and biomarker analyses.
| Study group | Role | What they receive |
|---|---|---|
| Endometriosis Group | Experimental | Adult women with confirmed deep endometriosis undergoing collection of clinical data and biological samples, including blood, endometrial tissue, vaginal microbiota samples, and, when clinically indicated, additional samples collected during pelvic surgery. Receives: Procedure: Biological Sample Collection |
| Control Group | Active comparator | Adult women without endometriosis undergoing collection of clinical data and biological samples, including blood, endometrial tissue, vaginal microbiota samples, and, when clinically indicated, additional samples collected during pelvic surgery. Receives: Procedure: Biological Sample Collection |
What is being measured
The primary outcome is the main question the study is designed to answer.
CD39 Expression on Natural Killer Cells in Endometrial and Peritoneal Samples
Comparison of CD39 expression on natural killer (NK) cells in endometrial and peritoneal samples collected from women with deep endometriosis and women without endometriosis.
Measured: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Secondary outcomes (6)
NK Cell Cytotoxic Function
Assessment of NK cell cytotoxic activity through degranulation markers and cytokine production in biological samples.
Measured: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Endometrial and NK Cell Interactions
Evaluation of interactions between endometrial cells and NK cells using tissue-based analyses.
Measured: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Ex Vivo Modulation of NK Cell Function
Evaluation of the effects of cytokine stimulation on NK cell function and endometrial cell responses in laboratory assays.
Measured: Following sample collection, up to study completion (16 months)
Association Between Hormonal Levels and NK Cell Profile
Correlation of estrogen and progesterone levels with NK cell characteristics and immune markers.
Measured: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Association Between Clinical Characteristics and Immune Markers
Correlation between clinical features of endometriosis and immunological findings.
Measured: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Genetic Biomarker Associations
Assessment of associations between genetic markers and immunological findings.
Measured: At sample collection and laboratory analysis up to study completion (16 months)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jun 2026
- Study startJun 2026 (estimated)
- Primary completionOct 2027 (estimated)
- Study completionOct 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for EndometriosisStudies 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 N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Participants are assigned to one of two parallel groups according to disease status: women with confirmed deep endometriosis and women without endometriosis. Clinical data and biological samples are collected during the secretory phase of the menstrual cycle and compared between groups.
- Masking
- None (open label)
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hopital Foch
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Marie CARBONNEL, MD, Principal investigator, Foch hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07652593
- Sponsor's protocol ID
- 2024_0074
- Acronym
- PAINLESS
- Status last verified
- Jun 2026
- First submitted
- 11 Jun 2026
- Last updated
- 17 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Interaction Between Decidual Cells and Natural Killer Cells in Endometriosis: A Prospective Pilot Case-Control Study
- ClinicalTrials.gov ID
- NCT07652593
- Acronym / sponsor ID
- PAINLESS / 2024_0074
- Conditions
- Endometriosis
- Keywords
- Endometriosis, Deep Endometriosis, Natural Killer Cells, NK Cells, Endometrial Immune Microenvironment, CD39, Immunology, Vaginal Microbiota
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Hopital FochUniversity, hospital or other
- Study start
- Jun 2026 (estimated)
- Primary completion
- Oct 2027 (estimated)
- Study completion
- Oct 2027 (estimated)
- First posted
- 17 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Endometriosis is a chronic gynecological disease characterized by the presence of endometrial-like tissue outside the uterus and is frequently associated with pelvic pain and infertility. Increasing evidence suggests that immune dysfunction may contribute to the development and persistence of the disease.
The purpose of this prospective case-control study is to compare immune cell characteristics in women with deep endometriosis and women without endometriosis during the secretory phase of the menstrual cycle. Participants will undergo collection of clinical data, blood samples, endometrial samples, and vaginal microbiota samples. For participants undergoing clinically indicated pelvic surgery, additional biological samples may be collected during the procedure. The study aims to improve understanding of the immune mechanisms involved in endometriosis and to identify potential biomarkers associated with the disease.
Detailed description
Endometriosis affects approximately 10-15% of women of reproductive age and represents a major public health concern. Despite its high prevalence, the pathophysiological mechanisms underlying the disease remain incompletely understood. Increasing evidence suggests that alterations in the immune environment of the endometrium may contribute to the establishment and progression of endometriosis. In particular, uterine immune cells may play a role in regulating local inflammation and tissue homeostasis. Characterizing these immune mechanisms may improve understanding of disease development and identify potential biomarkers associated with endometriosis.
PAINLESS is a prospective, single-center, pilot case-control study conducted at Foch Hospital (Suresnes, France). The study will enroll 50 adult women, including 25 participants with confirmed deep endometriosis and 25 control participants without endometriosis.
Biological samples will be collected during the secretory phase of the menstrual cycle (days 16-24). Depending on clinical management, study procedures may include:
- Collection of demographic and clinical data
- Assessment of symptoms and quality of life
- Blood sampling
- Endometrial sampling
- Vaginal microbiota sampling
- Collection of additional biological specimens during clinically indicated pelvic surgery.
Biological samples will be analyzed to characterize immune cell populations, evaluate soluble immune mediators, investigate associations with hormonal and clinical parameters, and explore biological mechanisms involved in endometriosis.The primary objective is to compare the expression of immune-related markers in endometrial and peritoneal samples obtained from women with endometriosis and controls. Secondary objectives include characterization of immune cell phenotypes and functions, evaluation of immune-related soluble factors, investigation of interactions between immune and endometrial cells, assessment of correlations with hormonal and clinical data, exploratory genetic analyses, and creation of a vaginal microbiota biobank. Results from this pilot study are expected to provide preliminary data for future research aimed at improving the understanding, diagnosis, and management of endometriosis.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants are assigned to one of two parallel groups according to disease status: women with confirmed deep endometriosis and women without endometriosis. Clinical data and biological samples are collected during the secretory phase of the menstrual cycle and compared between groups.
| Arm | Type | Receives |
|---|---|---|
| Endometriosis Group | Experimental | Procedure: Biological Sample CollectionAdult women with confirmed deep endometriosis undergoing collection of clinical data and biological samples, including blood, endometrial tissue, vaginal microbiota samples, and, when clinically indicated, additional samples collected during pelvic surgery. |
| Control Group | Active comparator | Procedure: Biological Sample CollectionAdult women without endometriosis undergoing collection of clinical data and biological samples, including blood, endometrial tissue, vaginal microbiota samples, and, when clinically indicated, additional samples collected during pelvic surgery. |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (16 listed)
- Endometriosis Group
- Female participant aged 18 years or older.
- Confirmed diagnosis of deep endometriosis by imaging or surgery.
- Pelvic pain and/or severe dysmenorrhea (Visual Analog Scale > 4).
- Premenopausal.
Key exclusion criteria (7 listed)
- Current infection.
- Active cancer.
- Active autoimmune disease.
- Concomitant hormonal treatment.
- Pregnancy.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Biological Sample CollectionCollection of blood samples, endometrial samples, vaginal microbiota samples, and surgical specimens when clinically indicated for immunological and biomarker analyses. | Procedure or surgery | Control Group, Endometriosis Group |
Primary outcome
CD39 Expression on Natural Killer Cells in Endometrial and Peritoneal Samples
Time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Comparison of CD39 expression on natural killer (NK) cells in endometrial and peritoneal samples collected from women with deep endometriosis and women without endometriosis.
6 secondary outcomes
NK Cell Cytotoxic Function
Time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Endometrial and NK Cell Interactions
Time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Ex Vivo Modulation of NK Cell Function
Time frame: Following sample collection, up to study completion (16 months)
Association Between Hormonal Levels and NK Cell Profile
Time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Association Between Clinical Characteristics and Immune Markers
Time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)
Genetic Biomarker Associations
Time frame: At sample collection and laboratory analysis up to study completion (16 months)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jun 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Marie CARBONNEL, MD principal investigator
Foch hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Biological Sample Collection in people with Endometriosis, run by Hopital Foch at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 16 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 17 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Florence Couppey, clinical project manager (+33 (0)1 46 25 31 30, f.couppey@hopital-foch.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
CD39 Expression on Natural Killer Cells in Endometrial and Peritoneal Samples (time frame: At sample collection during the secretory phase of the menstrual cycle (Days 16-24)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Jun 2026.