Chlamydia, Gonorrhea, Syphilis Infection
Conditions
Keywords
DoxyPEP, MSM, Syphilis, gonorrhea, Chlamydia, Prevention
Brief summary
The objective of this research is to evaluate the efficacy and safety of doxycycline in MSM for preventing sexually transmitted infections (gonorrhea, chlamydia, and syphilis) in Thailand Participation in this study will last approximately 12 weeks and will include 2-3 clinic visits, along with 10-11 follow-up phone contacts over a period of 11 weeks.
Interventions
DRUGDoxycycline (200mg/day)
Doxycycline 200 mg single dose after unprotected sex within 24-72 hours
Sponsors
Bangrak STIs Center
Mahidol University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Masking description
Labotatory staffs
Intervention model description
This study is designed as a randomized controlled trial (RCT). Participants will be randomly assigned to either the intervention group or the control group in a 2:1 ratio using simple randomization. The intervention group will receive doxycycline for the prevention of sexually transmitted infections (gonorrhea, chlamydia, and syphilis) for a period of 3 months. The control group will receive standard-of-care services and a brief educational session on sexually transmitted infection prevention at the start of the study. All participants will be tested for bacterial sexually transmitted infections (syphilis, gonorrhea, and chlamydia) at baseline and again at the end of the study after completing 12 weeks of follow-up. Before randomization, eligible participants will complete a questionnaire assessing knowledge, attitudes, and preventive behaviors related to sexually transmitted infections. In-depth interviews will also be conducted among men who have sex with men (MSM) at risk due
Eligibility
Sex/Gender
MALE
Age
18 Days to 60 Days
Healthy volunteers
Yes
Inclusion criteria
Biological male, aged not over 60 years Thai nationality Able to read, communicate, and understand the Thai language Men who have sex with men (MSM), aged 18 years or older and not over 60 years Having at least one of the following risk factors: A history of condomless sex, or condom failure (breakage, leakage, or slippage), via any sexual route with at least two sexual partners within the past 3 months A diagnosis of gonorrhea, chlamydia, or syphilis within the past 6 months Current use of HIV pre-exposure prophylaxis (PrEP) Willing and able to participate in study procedures (e.g., able to return to the clinic for scheduled testing for gonorrhea, chlamydia, and syphilis; able to complete doxycycline use records; and able to receive follow-up phone calls from the research team) Willing and able to provide written informed consent to participate in the study \-
Exclusion criteria
* History of allergy to tetracycline-class antibiotics Diagnosed with syphilis and not yet treated, or currently receiving treatment with benzathine penicillin G or doxycycline Receipt of benzathine penicillin G within the past 12 weeks Prior receipt of a gonorrhea vaccine Current use of medications or products that may interact with doxycycline, including: Vitamin A derivatives (e.g., isotretinoin, acitretin) Antiepileptic drugs (e.g., phenytoin, carbamazepine, phenobarbital) Immunosuppressive agents (e.g., methotrexate) Medications for heart failure or cardiac arrhythmias (e.g., digoxin) Anticoagulants (e.g., warfarin) Use of oral or injectable medications that affect blood cells, such as anticancer drugs, chemotherapy, systemic corticosteroids, or targeted therapies History of renal impairment (eGFR \< 60 mL/min/1.73 m²) or hepatic impairment (AST or ALT \> 3 times the upper limit of normal) Uncontrolled or unstable underlying diseases, such as hematologic disorders, cancer, autoimmune diseases, or neurological disorders Severe medical or psychiatric conditions that, in the investigator's judgment, may increase study-related risk or impair the participant's ability to provide informed consent Alcohol dependence (inability to control alcohol consumption, withdrawal symptoms upon reduction or cessation, or continued use despite harm) or illicit drug dependence (regular, uncontrolled use) within the past 12 months prior to enrollment, which may affect doxycycline use for STI prevention Previous participation in this study with prior randomization
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| To evaluate the efficacy of doxycycline in preventing sexually transmitted infections (gonorrhea, chlamydia, and syphilis) among men who have sex with men in Thailand. | 12 weeks | Measure the proportion of participants who test positive by NAAT for gonorrhea or chlamydia at any anatomical site (genital, pharyngeal, or rectal), or who are diagnosed with syphilis during the study period. |
Countries
Thailand
Contacts
CONTACTRossapnorn Kittiyaowamarn, MD
CONTACTKittipoom Chinhiran, MD
PRINCIPAL_INVESTIGATORRossaphorn KITTIYAOWAMARN, MD
Bangrak STIs Center
Outcome results
None listed