Chlamydia Trachomatis Genital InfectionURSAFE-CTNCT07596316
Using Urine to Study Antibodies & Functional Cell-Mediated Immunity in the Context of Chlamydia Trachomatis
An observational study of Chlamydia Trachomatis Genital Infection, run by Universiteit Antwerpen at 1 site in Belgium.
Trial summary
The goal of this observational study is to learn if we can identify immune biomarkers in first-void urine and vaginal brush samples in Chlamydia trachomatis (CT) positive adult women. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Chlamydia Trachomatis Genital Infection
- What is being tested?
- Sampling
- Type of treatment
- Medical device
- How many people
- 73 participants
- Where
- 1 siteBelgium
- Study dates
- 10 Dec 2025to Jun 2027
- Phase
- Observational
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
Study population: A total of 73 Chlamydia positive female participants will be included.
Who may be able to join
- Female
- Chlamydia trachomatis NAAT positive vaginal sample or first-void urine sample.
- Able to understand the information brochure and what the study is about.
- Willing to give informed consent to use their samples for details described in the study protocol.
Who cannot join
- Pregnancy (self-reported)
- Being positive for Human Immunodeficiency Virus (HIV)
- Women that underwent hysterectomy.
- Menstruation at the time of sample collection.
- Current use of antibiotics effective against Chlamydia trachomatis (doxycyline or azithromycine) or use of such antimicrobials in the past 14 days before participating in the study.
- Participating in another clinical trial at the same time of participating in this study.
- Having a history or current evidence of any condition or abnormality that might confound the results of the study or is not in the best interest of the individual to participate, in the opinion of the investigator.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site, 1 recruiting
- Recruiting
Violett Antwerp
Antwerp, Antwerp, 2000
Ward Bauwens, MD, +32 3 293 95 91, info@violett.be
About this study
The goal of this observational study is to learn if we can identify immune biomarkers in first-void urine and vaginal brush samples in Chlamydia trachomatis (CT) positive adult women. Participants will self-collect a first-void urine sample, self-collect a vaginal brush, and a blood sample will be collected by a healthcare worker. Participants will complete a questionnaire.
Read the detailed description
To date, clinician-collected blood samples are still the primary methods to monitor immune responses to genital tract infections. Replacing these samples with a specimen that is non-invasive and can be self-collected, such as the initial or first-void urine stream or vaginal brushes, could have important acceptance and feasibility advantages and could facilitate the logistics of clinical trials and future epidemiological or vaccine studies. Moreover, these local samples give more information on the immune response at the site of infection, in the genital tract. Initial results of experiments using first-void urine samples and cervicovaginal brushes for immune response monitoring are promising. However, no standardized method for the detection of (functional) Chlamydia trachomatis (CT)-specific immune responses is available to be used on first-void urine or vaginal samples. Therefore, the aim of this pilot study is to determine feasibility to detect mucosal immune responses in first-void urine and self-collected vaginal samples. Furthermore, we will compare local immune responses with systemic immunity.
The primary objectives of this study are:
- To explore the feasibility to detect (functional) CT-specific antibodies and CT-specific cellular immune responses in first-void urine or self-collected vaginal samples.
- To compare levels of total and CT-specific antibodies in first-void urine and serum.
- To compare mucosal and systemic CT-specific cellular immune responses in mucosal mononuclear cells derived from first-void urine or self-collected vaginal samples, and peripheral blood mononuclear cells (PBMCs).
A total of 73 female participants will be included in this trial. Women that can be included have to be positive for a Chlamydia trachomatis nuclear acid amplification test (NAAT) on a vaginal or FVU sample, and have not yet been treated with antibiotic therapy.
The study described is a low-interventional observational study. Participants will self-collect a first-void urine sample using a 20 mL Colli Pee® device (Novosanis), followed by a vaginal brush (Evalyn® brush, Rovers). Medical personnel at the study site will collect a blood sample (one serum tube and 2 heparin tubes). Furthermore, personal data is collected via a paper-based questionnaire.
- Conditions
- Chlamydia Trachomatis Genital Infection
- Being tested
- Sampling
- Keywords
- first-void urine, Colli Pee, Chlamydia, Mucosal immunity
- Medical subject headings
- Chlamydia Infections
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SamplingDevice
Collection of first-void urine (i.e. the initial stream of urine) with the Colli-Pee device (Novosanis, Belgium) (one sample of approx. 20 mL).
Collection of a vaginal brush sample with the Evalyn brush (Rovers Medical Devices, The Netherlands).
Collection of blood samples (three blood tubes of approx. 9 mL).
What is being measured
The primary outcome is the main question the study is designed to answer.
Concentration of total and Chlamydia-specific immunoglobulins in first-void urine and serum samples
Concentration of total and Chlamydia-specific immunoglobulins in first-void urine and serum samples determined using ELISA-based assays and the correlation of antibody titers between both sample types.
Measured: Within 6 months after study completion
Number of Chlamydia-specific SFCs per million cells
Quantification of antigen-specific cells in cells isolated from first-void urine samples, vaginal brush samples and whole blood samples (PBMC) using ELISpot-based assays.
Measured: Within 6 months after study completion
Measurement of percentage and median fluorescence intensity (MFI) of immune cell subsets in blood, first-void urine and vaginal brush samples.
Measuring percentage and MFI of immune cell subsets using flow cytometry
Measured: Within 6 months after study completion.
Secondary outcomes (2)
STI DNA status of first-void urine and vaginal brush samples.
Nuclear acid amplification test for the presence of DNA from different sexually transmitted infections (including Chlamydia, Mycoplasma genitalium, Mycoplasma hominis, Neisseria gonorrhea, Trichomonas vaginalis, Ureaplasma parvum, Ureaplasma urealyticum) to investigate Chlamydia clearance or persistent infection and determine coinfections.
Measured: Within 6 months after study completion.
Other biomarkers
To test other biomarkers to normalize immune biomarkers measured in primary outcomes (antibody or cellular immune responses), for example total IgG, IgG subclasses, total protein, total human DNA etc.
Measured: Within 6 months after study completion.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 May 2026
- Study start10 Dec 2025
- Primary completionJun 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Chlamydia Trachomatis Genital InfectionStudies 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
- Observational
- Observational model
- Case only
- Time perspective
- Cross-sectional
- Enrolment
- 73 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universiteit Antwerpen
- Sponsor type
- University, hospital or other
- Collaborators
- Violett Antwerp
- Responsible party
- Principal investigator, Paolo Palma, Universiteit Antwerpen
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07596316
- Sponsor's protocol ID
- B3002025000147
- Acronym
- URSAFE-CT
- Status last verified
- May 2026
- First submitted
- 12 May 2026
- Last updated
- 19 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No