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TransgenderXCVDNCT05334888

Sex-differential Host-microbiome CVD Risk - A Longitudinal Cohort Approach

An observational study of Transgender and Gut Microbiome, run by Charite University, Berlin, Germany at 1 site in Germany.

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

The XCVD study investigates the influence of sex hormones on the composition of the gut microbiome and the possible emergence of cardiovascular risk factors. It will follow 200 healthy transgender individuals for five years during their hormone replacement therapy (HRT) and analyze them for the possible emergence of… Read more about this study

Who is it for?
Ages 18 to 50 years
Conditions the study is for
Transgender, Gut Microbiome, Immune System
How many people
200 participants
Where
1 siteGermany
Study dates
29 Aug 2022to 31 Dec 2030
How long will I take part?
2 Years
Phase
Observational
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 to 50 years
  • All sexes
  • Adult

Study population: Healthy transgender individuals during their gender hormone replacement therapy (HRT)

Who may be able to join

  • Age 18-50
  • Language requirements: German, English
  • Previous gender hormone replacement therapy (HRT).
  • Ability to give consent and written consent to participate.
  • Health insurance (for clarification of incidental findings)

Who cannot join

  • Diseases or functional disorders that, in the opinion of the study physician, preclude participation in the study.
  • Incapacity or other circumstances that do not allow study participants to fully understand the nature, significance and scope of this study.

Trial locations and contacts

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

Sofia Forslund, Prof. Dr. contact

+49 30 450540649

sofia.forslund@mdc-berlin.de

Lajos Marko, Dr. contact

lajos.marko@charite.de

Germany1 site, 1 recruiting

  • Experimental and Clinical Research Center, Clinical Research Unit

    Berlin, 13125

    Michael Boschmann, MD, +4930450540241, michael.boschmann@charite.de

    Lajos Marko, MD, PhD, +4930450540144, lajos.marko@charite.de

    Recruiting

Other trials in Germany

About this study

Official title: Sex Hormone-specific Cardiovascular Risks in the Gut Microbiome-host Axis - A Longitudinal Cohort Study.

The XCVD study investigates the influence of sex hormones on the composition of the gut microbiome and the possible emergence of cardiovascular risk factors. It will follow 200 healthy transgender individuals for five years during their hormone replacement therapy (HRT) and analyze them for the possible emergence of cardiovascular risk factors in relation to changes in the gut microbiome, metabolome, and immunome. We would also like to phenotype cardiovascular disease.

Read the detailed description

Conducting this innovative study using established scientific methods such as omics platforms, systems biology, and careful CVD phenotyping will allow, for the first time, extensive data collection on the influence of sex hormones on the development of CVD risk factors as well as the role of the gut microbiome. In doing so, the influence of circulating sex hormones can also be quantified to potentially predict CVD risk markers.

Keywords
Transgender Medicine

What is being measured

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

  1. Changes in relative species abundance of intestinal bacteria compared

    baseline and 2 years and 5 years after initiation of hormone replacement therapy.

    stool samples: Analysis with 16s rRNA sequencing

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

Secondary outcomes (34)

  1. Changes in cardio marker

    sera: following cardio marker can be determined by Electro Chemiluminescence Immuno-Assay: BNP and hs-troponin.

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  2. Changes in hormone parameters

    sera: following hormones can be determined by mass spectrometry: Free Androgen Index (fAI), Beta-CrossLaps (BCTX), Carboxy-terminal Propeptide of Procollagen I (P1CP), Luteinizing Hormone, Oestradiol, Progesterone, Testosterone, Free Testosterone, Sex Hormone Binding Globulin, Dihydrotestosterone, Oestron, Free Oestriol.

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  3. Changes in immune marker

    sera: pro- and anti-inflammatory cytokines using cytokine - multiplex panel and Immune cell populations with shotgun sequencing

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  4. Changes in the concentration of of cortisol, progesterone, testosterone and dehydroepiandrosterone

    Hair sample: Hair steroid analysis with Immunoassay and LC-MS/MS

    Measured: Baseline, 2 years and 5 years Follow Up (optional: one year follow up)

  5. Changes in the oral species abundance

    saliva sample / oral / mouth: species abundance of oral bacteria (sequencing)

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  6. Changes in Immune cell marker / regulatory T-cells

    Whole blood samples for Immune cell populations and peripheral blood mononuclear cells RNA isolation for whole-transcriptome shotgun sequencing.

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  7. Changes in Epigenomics

    Whole blood samples for Immune cell populations and peripheral blood mononuclear cells RNA isolation for whole-transcriptome shotgun sequencing.

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  8. Changes in Proteomics

    sera: MS and ELISA

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  9. Changes in Metabolomics

    sera: MS and ELISA

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  10. Changes in relative species abundance of skin microbioma

    skin swab: DNA - sequencing

    Measured: Baseline, 2 years Follow Up (optional: after 1 year Follow Up)

  11. Changes in BMI

    body mass index (kg/m²)

    Measured: Baseline, 2 years Follow Up (optional: after 1 year Follow Up)

  12. Changes in circumference

    circumference measurement (cm): waist and hip

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  13. Gender identity

    questionnaire: Transgender Congruence Scale (TCS) \& gender dysphoria

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  14. Changes in physical activity

    questionnaire: International Physical Activity Questionnaire / IPAQ

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  15. Changes in mental health

    questionnaire: Generalized Anxiety Disorder / GAD-7

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  16. Changes in Perceived Stress

    questionnaire: Perceived Stress Questionnaire / PSQ

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  17. Changes in quality of life

    questionnaire: quality of life / PROMIS

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  18. Changes in depression

    questionnaire: Beck-Depressions-Inventar Revision / BDI II \& The Patient Health Questionnaire (PHQ-9)

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  19. Changes in chrono type / sleep-wake behaviour

    questionnaire: Munich ChronoType Questionnaire (MCTQ)

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  20. Changes in dietary habits

    Food Frequency Quenstionnaire /FFQ, special diet and intake of dietary supplements, prebiotics and probiotics

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  21. Changes in socio-demographics

    Family status, education level, current working status, and living situation

    Measured: Baseline, 12, 24, 48 and 60 months Follow Up

  22. Documentation of HRT

    HRT medication, dosing, regimes, and progress as well as all transition -relevant surgery and physical changes

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  23. Changes in vital signs

    Systolic and diastolic blood pressure and heart rate

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  24. Changes in life style risk parameters

    Smoking status, alcohol consumption and use of recreational drugs

    Measured: Baseline, 6, 12, 18, 24, 36, 48 and 60 months Follow Up

  25. Changes in CVD risk scores

    Framingham risk scores (FRS) and Systematic Coronary Risk Evaluation (SCORE)

    Measured: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)

  26. Changes in FVC (in liters)

    Lung function: spirometry

    Measured: Baseline, 2 years & 5 years Follow Up (optional: one year follow up)

  27. Changes in FEV1 (in liters)

    lung function: spirometry

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow up)

  28. Changes FEV1/FVC (in %)

    Lung function: spirometry

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow up)

  29. Changes in fatmass (kg)

    Body composition

    Measured: Baseline, 2 years and 5 years Follow up (optional: one year follow up)

  30. Changes in fatmass (%)

    Body composition

    Measured: Baselie, 2- and 5 years follow-up (optional: one year follow up)

  31. Changes in fat-free mass (in kg)

    Body composition

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow-up)

  32. Changes in fat-free mass (in %)

    Body composition

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow-up)

  33. Changes in body cell mass (in kg)

    Body composition

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow-up)

  34. Changes in total body water (in liters)

    Body composition

    Measured: Baseline, 2- and 5 years follow-up (optional: one year follow-up)

Timeline

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

  1. First posted19 Apr 2022
  2. Study start29 Aug 2022
  3. Primary completion31 Dec 2030 (estimated)
  4. Study completion31 Dec 2030 (estimated)

Resources

More details

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

Study design
Study type
Observational
Observational model
Cohort
Time perspective
Prospective
Enrolment
200 participants (estimated)
Target duration
2 Years
IDs, dates and publications
ClinicalTrials.gov ID
NCT05334888
Sponsor's protocol ID
ChariteU - ECRC XCVD
Acronym
XCVD
Status last verified
Jun 2026
First submitted
4 Apr 2022
Last updated
15 Jun 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Fromentin S, Forslund SK, Chechi K, Aron-Wisnewsky J, Chakaroun R, Nielsen T, Tremaroli V, Ji B, Prifti E, Myridakis A, Chilloux J, Andrikopoulos P, Fan Y, Olanipekun MT, Alves R, Adiouch S, Bar N, Talmor-Barkan Y, Belda E, Caesar R, Coelho LP, Falony G, Fellahi S, Galan P, Galleron N, Helft G, Hoyles L, Isnard R, Le Chatelier E, Julienne H, Olsson L, Pedersen HK, Pons N, Quinquis B, Rouault C, Roume H, Salem JE, Schmidt TSB, Vieira-Silva S, Li P, Zimmermann-Kogadeeva M, Lewinter C, Sondertoft NB, Hansen TH, Gauguier D, Gotze JP, Kober L, Kornowski R, Vestergaard H, Hansen T, Zucker JD, Hercberg S, Letunic I, Backhed F, Oppert JM, Nielsen J, Raes J, Bork P, Stumvoll M, Segal E, Clement K, Dumas ME, Ehrlich SD, Pedersen O. Microbiome and metabolome features of the cardiometabolic disease spectrum. Nat Med. 2022 Feb;28(2):303-314. doi: 10.1038/s41591-022-01688-4. Epub 2022 Feb 17.

    PubMed 35177860

  • Talmor-Barkan Y, Bar N, Shaul AA, Shahaf N, Godneva A, Bussi Y, Lotan-Pompan M, Weinberger A, Shechter A, Chezar-Azerrad C, Arow Z, Hammer Y, Chechi K, Forslund SK, Fromentin S, Dumas ME, Ehrlich SD, Pedersen O, Kornowski R, Segal E. Metabolomic and microbiome profiling reveals personalized risk factors for coronary artery disease. Nat Med. 2022 Feb;28(2):295-302. doi: 10.1038/s41591-022-01686-6. Epub 2022 Feb 17.

    PubMed 35177859

  • Franz K, Marko L, Mahler A, Chakaroun R, Heinitz S, Schlogl H, Sacher J, Steckhan N, Dechend R, Adams N, Andersen M, Glintborg D, Viehweger M, Bahr LS, Forslund-Startceva SK. Sex hormone-dependent host-microbiome interactions and cardiovascular risk (XCVD): design of a longitudinal multi-omics cohort study. BMJ Open. 2025 Jan 9;15(1):e087982. doi: 10.1136/bmjopen-2024-087982.

    PubMed 39788783

Questions about this trial

What is this clinical trial studying?

An observational study of Transgender and Gut Microbiome, run by Charite University, Berlin, Germany at 1 site in Germany.

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 5 inclusion and 2 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: looking for participants now, as of the sponsor's last update on 15 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 Germany. 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 Sofia Forslund, Prof. Dr. (+49 30 450540649, sofia.forslund@mdc-berlin.de), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Changes in relative species abundance of intestinal bacteria compared (time frame: Baseline, 2 years and 5 years Follow Up (optional: after 1 year Follow Up)). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05334888, which also lists 3 linked publications.

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 15 Jun 2026.

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