Assessment of Drug-drug Interactions Between Masculinizing Hormone Therapy and Antiretroviral Agents Concomitantly for Pre-exposure Prophylaxis Among Transgender Men

  • End date
    Oct 1, 2022
  • participants needed
  • sponsor
    Thai Red Cross AIDS Research Centre
Updated on 26 January 2021


There are currently no published studies addressing drug-drug interactions (DDI) between masculinizing hormone therapy (MHT) and pre-exposure prophylaxis (PrEP) among transgender men (TGM). This could lead to concerns and subsequent prioritizing MHT over PrEP among TGM. Because tenofovir alafenamide (TAF) can achieve higher intracellular tenofovir diphosphate (TFV-DP) levels with lower tenofovir plasma concentrations, it is promising that both plasma tenofovir (TFV) and intracellular TFV-DP levels might not be significantly affected by MHT. The current study aims to determine the pharmacokinetics (PK) DDI between MHT and daily PrEP among TGM.

Condition Drug interaction, drug interactions, drug-drug interaction
Treatment Emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg (F/TDF) and emtricitabine 200 mg/tenofovir alafenamide 25 mg (F/TAF)
Clinical Study IdentifierNCT04593680
SponsorThai Red Cross AIDS Research Centre
Last Modified on26 January 2021


Yes No Not Sure

Inclusion Criteria

Thai nationality
Age 18-40 years old
Female-to-Male transgender individual
Body mass index 18.5-24.9 kg/m2
Negative urine pregnancy test
Calculated creatinine clearance (CrCl) 60 mL/min, as estimated by the Cockcroft-Gault equation
Alanine aminotransferase (ALT) 2.5 x ULN
Signed the informed consent form

Exclusion Criteria

Known history of allergy to hormonal component to be used in the study
Use of pre-exposure prophylaxis or post-exposure prophylaxis in the past 30 days
Use of injectable MHT in the past 3 months
Evidence of current hepatitis B virus infection (HBV) - i.e. hepatitis B surface antigen [HBsAg] positive
Evidence of current hepatitis C virus infection (HCV) - i.e. HCV antibody positive
History of myocardial infarction or coronary artery disease
Current use of any of the following
Anticonvulsants: carbamazepine, oxcarbazepine, phenytoin, or phenobarbital
Herbs: gingko biloba, St John's wort or milk thistle
Anti-infective agents: protease inhibitors, rifampicin or rifabutin
History of gastrointestinal tract surgery that alter gastrointestinal tract and/or drug absorption
Alcohol or drug use that, in the opinion of the investigator, would interfere with completion of study procedures
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