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STI Prophylaxis and Emergence of Antimicrobial Resistance (SPEAR)

University College London (UCL) logo

University College London (UCL)

Status

Enrolling

Conditions

Doxycycline
Sexually Transmitted Infection (STI) Prevention
Microbiome
Antibiotic Resistance, Bacterial
Antibiotic Prophylaxis

Study type

Observational

Funder types

Other

Identifiers

NCT06778083
174194
REC Ref: 24/EM/0282 (Other Identifier)

Details and patient eligibility

About

The goal of this observational study is to understand the risk of antibiotic resistance and changes in the human microbiome (bacteria that live inside and on us), if people use antibiotics to prevent sexually transmitted infections (STI prophylaxis, doxycycline post-exposure prophylaxis, or 'doxyPEP'). The study will assess how easy and acceptable it is to find antibiotic resistance and microbiome changes in the throats and guts of men-who-have-sex-with-men (MSM) who use STI prophylaxis.

The study will recruit 108 MSM who are using and not using STI prophylaxis. Participants will visit the clinic every 6 months. At each visit, they will provide a throat swab and stool sample, and complete a questionnaire. DNA of the bacteria from the samples will be analysed to identify the bacteria and look for antibiotic resistance.

Enrollment

108 estimated patients

Sex

Male

Ages

18+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

  • Aged ≥ 18 years.
  • Identifies as a man (cis or trans).
  • Has sex with men.
  • Able to provide informed consent.

Exclusion criteria

  • Use of an antibiotic other than doxycycline in the 3 months prior to enrolment
  • Currently being treated for an STI with doxycycline
  • Use of doxycycline within the prior 3 months for an indication other than STI treatment or STI prevention.

Trial design

108 participants in 3 patient groups

DoxyPEP users
Description:
Previous use of doxycycline post-exposure prophylaxis within 3 months of baseline visit.
Doxycycline treatment
Description:
Previous use of doxycycline for STI treatment within 3 months of baseline visit. Once enrolled all participants may use doxycycline post-exposure prophylaxis.
No antibiotics
Description:
No antibiotics within previous 3 months of baseline visit. Once enrolled all participants may use doxycycline post-exposure prophylaxis.

Trial documents
1

Trial contacts and locations

1

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Central trial contact

Manik Kohli, MBChB MSc

Data sourced from clinicaltrials.gov

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