Clinical trial NCT06778083: STI Prophylaxis and Emergence of Antimicrobial Resistance
Official title: STI Prophylaxis and Emergence of Antimicrobial Resistance
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Sexually Transmitted Infection (STI) Prevention
Antibiotic Prophylaxis
Antibiotic Resistance, Bacterial
Microbiome
Doxycycline
Keywords: DoxyPEP
STI Prophylaxis
Doxycycline
STI Prevention
Antimicrobial Resistance
Antibiotic Resistance
Microbiome
Men-who-have-sex-with-men
Lead sponsor: University College, London
Sponsor class: OTHER
Collaborators: name: University of Oxford
First posted: 2025-01-16
Enrollment: 108
Sex: MALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Men-who-have-sex-with men aged ≥ 18 years living in the United Kingdom. Target of 108 participants, with minimum 40 participants living with HIV.

Brief summary: 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.


Eligibility criteria: 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.

Primary outcomes:
measure: Detection of antimicrobial resistance genes of interest and characterisation of microbiome
timeFrame: From enrolment to 12 months
Secondary outcomes:
measure: Detection of differences in prevalence of antimicrobial resistance genes of interest between people using and not using antibiotic STI prophylaxis.
timeFrame: From enrolment to 12 months
measure: Detection of differences in microbiome between people using and not using antibiotic STI prophylaxis.
timeFrame: From enrolment to 12 months
measure: Change over time in prevalence of antimicrobial resistance genes of interest between people using and not using antibiotic STI prophylaxis.
timeFrame: From enrolment to 12 months
measure: Change over time in microbiome between people using and not using antibiotic STI prophylaxis.
timeFrame: From enrolment to 12 months
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: Central and North West London NHS Foundation Trust
Study officials:
References:
citation: Kohli M, Reid D, Pulford CV, Howarth A, Brown J, Mohammed H, Hughes G, Mercer CH, Saunders J. Choice of antibiotics for prophylaxis of bacterial STIs among individuals currently self-sourcing. Sex Transm Infect. 2022 Mar;98(2):158. doi: 10.1136/sextrans-2021-055310. Epub 2021 Dec 6. No abstract available.
citation: Kohli M, Medland N, Fifer H, Saunders J. BASHH updated position statement on doxycycline as prophylaxis for sexually transmitted infections. Sex Transm Infect. 2022 May;98(3):235-236. doi: 10.1136/sextrans-2022-055425. No abstract available.
citation: Chu VT, Glascock A, Donnell D, Grabow C, Brown CE, Ward R, Love C, Kalantar KL, Cohen SE, Cannon C, Woodworth MH, Kelley CF, Celum C, Luetkemeyer AF, Langelier CR. Impact of doxycycline post-exposure prophylaxis for sexually transmitted infections on the gut microbiome and antimicrobial resistome. Nat Med. 2025 Jan;31(1):207-217. doi: 10.1038/s41591-024-03274-2. Epub 2024 Oct 3.
citation: Molina JM, Charreau I, Chidiac C, Pialoux G, Cua E, Delaugerre C, Capitant C, Rojas-Castro D, Fonsart J, Bercot B, Bebear C, Cotte L, Robineau O, Raffi F, Charbonneau P, Aslan A, Chas J, Niedbalski L, Spire B, Sagaon-Teyssier L, Carette D, Mestre SL, Dore V, Meyer L; ANRS IPERGAY Study Group. Post-exposure prophylaxis with doxycycline to prevent sexually transmitted infections in men who have sex with men: an open-label randomised substudy of the ANRS IPERGAY trial. Lancet Infect Dis. 2018 Mar;18(3):308-317. doi: 10.1016/S1473-3099(17)30725-9. Epub 2017 Dec 8.
citation: Molina JM, Bercot B, Assoumou L, Rubenstein E, Algarte-Genin M, Pialoux G, Katlama C, Surgers L, Bebear C, Dupin N, Ouattara M, Slama L, Pavie J, Duvivier C, Loze B, Goldwirt L, Gibowski S, Ollivier M, Ghosn J, Costagliola D; ANRS 174 DOXYVAC Study Group. Doxycycline prophylaxis and meningococcal group B vaccine to prevent bacterial sexually transmitted infections in France (ANRS 174 DOXYVAC): a multicentre, open-label, randomised trial with a 2 x 2 factorial design. Lancet Infect Dis. 2024 Oct;24(10):1093-1104. doi: 10.1016/S1473-3099(24)00236-6. Epub 2024 May 23.
citation: Luetkemeyer AF, Donnell D, Dombrowski JC, Cohen S, Grabow C, Brown CE, Malinski C, Perkins R, Nasser M, Lopez C, Vittinghoff E, Buchbinder SP, Scott H, Charlebois ED, Havlir DV, Soge OO, Celum C; DoxyPEP Study Team. Postexposure Doxycycline to Prevent Bacterial Sexually Transmitted Infections. N Engl J Med. 2023 Apr 6;388(14):1296-1306. doi: 10.1056/NEJMoa2211934.