An observational study in Substance Use, HIV Prevention and Sexually Transmitted Infections (STIs), sponsored by Institute of HIV Research and Innovation Foundation, Thailand. Recruiting at 1 site in Thailand. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-06.
Sponsored by Institute of HIV Research and Innovation Foundation, Thailand · Observational
The study is a pre-implementation cross-sectional study exploring chemsex behaviors among transgender persons and gathering perspectives from multiple stakeholders to inform the development of transgender-tailored harm reduction services.
This study is designed under the EPIS framework (Exploration and Preparation phases) to better understand chemsex use among transgender populations in Thailand.
The study aims to:
Data will be collected using a mixed-methods approach, including:
2,238 studies on the registry are indexed under Substance-Related Disorders; 409 are open to participants now.
This study's planned enrollment of 50 is below the median of 251 across 299 observational studies indexed under Substance-Related Disorders.
Browse Substance-Related Disorders studies →Institute of HIV Research and Innovation Foundation, Thailand is the lead sponsor of 13 studies on the registry; 8 are open to participants now.
Counted across the registry records on this site, refreshed daily.
G1: Transgender chemsex users
G2: Family / partners
G3: Stakeholders
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Transgender women and transgender men who are current or former chemsex users. Participants will take part in semi-structured in-depth interviews (IDIs) exploring chemsex behaviors, patterns of use, perceived impacts, and needs for transgender-tailored harm reduction services.
Behavioral: Understanding of chemsex patterns, impacts, and service needs among transgender persons
Family members, friends, or partners of transgender persons who have not engaged in chemsex. Participants will provide perspectives on the social, behavioral, and relational impacts of chemsex and support needs.
Behavioral: Understanding of chemsex patterns, impacts, and service needs among transgender persons
Stakeholders including healthcare providers, policy makers, law enforcement officers, counselors, public health professionals, and community leaders involved in care, policy, or regulation related to chemsex. Participants will be interviewed to identify system-level facilitators and barriers to implementation of services.
Behavioral: Understanding of chemsex patterns, impacts, and service needs among transgender persons
: During study period (single visit within \~12 months study duration)
Key themes on chemsex behaviors and service needs
Qualitative themes identified from semi-structured in-depth interviews, including: * Reasons for engaging in chemsex * Patterns of substance use * Perceived positive and negative impacts * Harm reduction practices * Needs for transgender-tailored services Themes will be identified using thematic analysis.
Time frame: At interview (single time point)
Barriers and facilitators to implementation of transgender-tailored chemsex services
Barriers and facilitators to implementation identified using the Consolidated Framework for Implementation Research (CFIR) domains based on stakeholder and participant interviews.
Time frame: At interview (single time point)
Chemsex-related behavioral and demographic characteristics
Descriptive characteristics of participants, including demographic data, substance use patterns, and behavioral risk factors collected via questionnaire.
Time frame: At interview (single time point)
HIV-related stigma score
HIV-related stigma will be assessed using the HIV Stigma Scale (HSS). The HSS is a validated instrument measuring multiple domains of stigma, including personalized stigma, disclosure concerns, negative self-image, and concerns with public attitudes. The total score ranges from 40 to 160, with higher scores indicating greater levels of HIV-related stigma (worse outcome) Score (range: 40-160)
Time frame: Baseline, Month 3, Month 6
Transgender-related stigma score
Transgender-related stigma will be measured using the Transgender Identity Survey (TIS) (or instrument used in the protocol). This scale assesses experiences of stigma, discrimination, and internalized transphobia. Unit of Measure: Score (range: 20-100)
Time frame: Baseline, Month 3, Month 6
PrEP adherence (self-reported adherence score)
Self-reported adherence will be measured using a standardized adherence questionnaire assessing the number of doses taken over the past 30 days. Scores range from 0 to 100%, with higher percentages indicating better adherence (better outcome). In addition, adherence will be objectively assessed using tenofovir diphosphate (TFV-DP) concentrations in dried blood spots. Unit of Measure: Percentage (%) Drug concentration (fmol/punch)
Time frame: Baseline, Month 3, Month 6
Intervention acceptability score
Description: Acceptability will be assessed using the System Usability Scale (SUS). The SUS is a 10-item questionnaire with scores ranging from 0 to 100, with higher scores indicating better usability and acceptability (better outcome). Score (range: 0-100)
Time frame: Month 3
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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Institute of HIV Research and Innovation Foundation, Thailand