Where syphilis bacteria live and whether they can spread from symptom-free sites in women and men who have sex with women

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational cohort will enroll adults with untreated early infectious or early latent syphilis who are cis-women, cis-men who have sex with women only, or nonbinary people with a penis who have sex with women. Researchers will collect samples from multiple anatomical sites (for example vaginal, anal, and other mucosal surfaces) and use molecular tests and viability assays to detect Treponema pallidum and determine if detected organisms are alive. Participants will be followed over time with repeat sampling to measure how long DNA and viable organisms are detectable. The study is being conducted at clinical sites in Melbourne and Shanghai and does not involve therapeutic interventions.

Why it matters

Who can join: the full rules

Inclusion Criteria:

\- 1. Any cis-woman, cis-MSW, or nonbinary individuals with a penis who have sex with women only, (who meet all other study criteria) 2. Aged ≥18 years of age, 3. At least one sexual partner in the last 12 months 4. One of either:

a. Untreated clinically suspected primary or secondary syphilis. i. Must have rash or lesion(s) clinically suggestive of early infectious syphilis infection.

ii. May have positive PCR result, positive Dark-ground Microscopy result, positive syphilis serology or positive point-of-care syphilis test, but these are not necessary at the time of enrolment.

b. Untreated early latent (no clinical signs indicative of primary or secondary syphilis) syphilis with positive syphilis serology or positive point-of-care test, and one or more of the following(11): i. A documented syphilis seroconversion within the prior 12 months. ii. A sustained (longer than 2 weeks) fourfold or greater increase in the titre in the prior 12 months in a person previously treated for syphilis.

iii. Unequivocal symptoms of primary or secondary syphilis within the prior 12 months.

iv. Contact in the prior 12 months with a sex partner who had untreated primary, secondary, or early latent syphilis.

v. Documented reactive nontreponemal and treponemal tests, and the only possible exposure occurred during the previous 12 months vi. RPR/VDRL titre \>= 1:64 5. Be willing and able to complete study procedures, including physical examination 6. Receiving syphilis treatment on the day of recruitment 7. Have sufficient language proficiency to understand the requirements of the study 8. Provide informed consent as per individual site's local ethics requirements

Exclusion Criteria:

1. Men, transwomen, or other people, with a penis, who have had any sexual contact, including kissing, oral sex or anal sex, with men (or any other individual with a penis) in the previous one year.
2. Individuals who have received antibiotic treatment within 1 month prior to enrolment, with the EXCEPTION of metronidazole.
3. Diagnosis of late latent syphilis (\>1 year) or latent syphilis of unknown duration.

Where it's running

• Burrell Street Clinic, Guy's and St Thomas'
  London, United Kingdom Recruiting
• Jefferiss Clinic St Mary's Hospital, Imperial College London
  London, United Kingdom Recruiting
• Mortimer Market Centre
  London, United Kingdom Recruiting
• Monash University
  Melbourne, Victoria, Australia Active not recruiting
• Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine
  Shanghai, Shanghai Municipality, China Not yet recruiting
• Shanghai Skin Disease Hospital
  Shanghai, Shanghai Municipality, China Not yet recruiting

Study contacts

• Principal investigator: Janet Towns — Monash University
• Study coordinator: Brigid M Scally
• Email: brigid.scally@monash.edu
• Phone: +61399039300

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.