One-time double dose of Descovy (F/TAF) in healthy adults

DD-PrEP: Pharmacokinetic Evaluation of Single Dosing With Two F/TAF Tablets Among Healthy Volunteers

Phase 1 Interventional Johns Hopkins University · NCT07349758

We will test a one-time double dose of two F/TAF (Descovy) tablets in healthy adults to see how long drug levels remain over 14 days for HIV PrEP.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment24 (estimated)
Ages18 Years and up
SexAll
SponsorJohns Hopkins University Academic / other
Locations1 site (Baltimore, Maryland)
Trial IDNCT07349758 on ClinicalTrials.gov

What this trial studies

This Phase 1 trial gives a single double dose (two tablets) of F/TAF (tenofovir alafenamide 50 mg/emtricitabine 400 mg) to healthy, HIV-negative adults and follows them for 14 days. Intensive pharmacokinetic sampling occurs immediately after dosing and becomes less frequent over the two-week follow-up to measure plasma and intracellular levels of TAF, tenofovir, FTC and their metabolites. The pharmacokinetic profiles will be used to inform the plausibility of alternate, less-frequent dosing regimens for oral PrEP. Enrollment requires good general health, adequate renal function, and agreement to use condoms and avoid other oral PrEP during the study.

Who should consider this trial

Good fit: Healthy adults aged 18 or older who are HIV-negative, have adequate kidney function (eGFR ≥70 mL/min/1.73 m2), have not used oral PrEP in the prior two months, and can attend frequent blood-draw visits and use condoms during the study.

Not a fit: People living with HIV, those with positive hepatitis B surface antigen, significant renal impairment, recent oral PrEP use, or prior gastrointestinal surgeries that alter absorption are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, the results could support less-frequent dosing options for oral PrEP, potentially improving convenience and adherence.

How similar studies have performed: Daily tenofovir-containing regimens (including Descovy) are effective for PrEP, but single-dose or intermittent double-dose approaches are largely untested and remain exploratory.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* ≥18 years of age, inclusive on the date of screening
* Provides written informed consent for the study
* Good general health, as determined by medical history, physical examination, vital signs, screening laboratory tests
* Non-reactive HIV test results within four weeks of enrollment
* An estimated glomerular filtration rate (eGFR) of ≥ 70 mL/min/1.73 m2 via the CKD-EPI 2021 eGFRCr equation
* Agrees to use condoms for all sexual events during study participation
* Willing to abstain from oral PrEP use outside of study products for the duration of the study

Exclusion Criteria:

* History of oral PrEP (F/TDF or F/TAF) use in the preceding two months
* Persons who have a reactive or positive HIV result from screening visit.
* Positive hepatitis B surface antigen (HBsAg) test
* Participants with a history of having a gastrectomy, colostomy, ileostomy, or any other procedure altering the gastrointestinal tract or drug absorption
* History of any behaviors that place the participant at high-risk for HIV acquisition (e.g., needle sharing, unprotected sex with ≥1 partner in the prior 2 weeks)
* Taking concomitant medications that that are known inducers/inhibitors of P-gp that would effect TAF absorption
* Pregnancy or lactation
* Any other condition or prior therapy that, in the opinion of the investigator, would preclude informed consent, make study participation unsafe, make the individual unsuitable for the study or unable to comply with the study requirements. Such conditions may include, but are not limited to, current or recent history of severe, progressive, or uncontrolled substance abuse, or renal, hepatic, hematological, gastrointestinal, endocrine, pulmonary, neurological, or cerebral disease

Where this trial is running

Baltimore, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Healthy VolunteerHIV PreventionHIV PrEPhealthy volunteer
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.