HIV InfectionsPhase 1NCT03670355

Pharmacokinetic and Safety Study of a 90 Day Intravaginal Ring Containing Tenofovir

A Phase 1 study testing Tenofovir (TFV) IVR in people with HIV Infections, run by National Institute of Allergy and Infectious Diseases (NIAID) at 3 sites in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

The purpose of this study is to evaluate the pharmacokinetics (PK) and safety of a 90-day intravaginal ring (IVR) containing tenofovir (TFV). Read more about this study

Who is it for?: Ages 18 to 45 years, women onlyHealthy volunteers can take part
Conditions the study is for: HIV Infections
What is being tested?: Tenofovir (TFV) IVR
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 49 participants
Where: 3 sitesUnited States
Study dates: 2 Jan 2019to 25 Sep 2019
Phase: Phase 1
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 45 years
Women only
Healthy volunteers accepted
Adult

Who may be able to join

Assigned female sex at birth
Note: Participants who are female at birth, who now identify as male, will not be excluded so long as they are not on female-to-male transition therapy.
Age 18 through 45 years (inclusive) at Screening, verified per site standard operating procedures (SOPs)
Able and willing to provide written informed consent to be screened for and enrolled in MTN-038
Able and willing to provide adequate locator information, as defined in site SOPs
Able to communicate in spoken and written English

Show all 23Show fewer

Available for all visits and able and willing to comply with all study procedural requirements
Willing to abstain from receptive vaginal or anal sexual activities for 72 hours prior to each clinical visit and for 72 hours after biopsy collection
Willing to use male condoms for penile-vaginal and penile-rectal sexual intercourse for the duration of study participation
Per participant report, using an effective method of contraception for at least 30 days (inclusive) prior to Enrollment, and intending to continue use of an effective method for the duration of study participation; effective methods include:
hormonal methods (except contraceptive vaginal ring)
intrauterine device (IUD)
sterilization (of participant or partner, as defined in site SOPs)
having sex exclusively with individuals assigned female sex at birth
sexually abstinent as defined by abstaining from penile-vaginal intercourse for 90 days prior to Enrollment, and intending to remain abstinent for the duration of study participation
In general good health as determined by the Investigator of Record (IoR)/designee at Screening and Enrollment
HIV-uninfected based on testing performed at Screening and Enrollment (per protocol algorithm in the study protocol)
Per participant report at Screening, regular menstrual cycles with at least 21 days between menses
Note: This criterion is not applicable to participants who report using a progestin-only method of contraception at Screening (e.g., Depo-Provera or levonorgestrel-releasing IUD) nor to participants using continuous combination oral contraceptive pills, as the absence of regular menstrual cycles is an expected, normal consequence in this context.
Per participant report at Screening and Enrollment, states a willingness to refrain from inserting any non-study vaginal and rectal products or objects into the vagina or rectum including, but not limited to spermicides, female condoms, diaphragms, intravaginal rings, vaginal or rectal medications, menstrual cups, cervical caps, douches, lubricants, and sex toys (vibrators, dildos, etc.) for the 24 hours preceding the Enrollment Visit and for the duration of study participation.
Note: Use of tampons is permitted except for 24 hours prior to clinic visits in which CVF samples are scheduled to be collected.
Participants over the age of 21 (inclusive) must have documentation of a satisfactory Pap within the past 3 years prior to Enrollment consistent with Grade 0 according to the Female Genital Grading Table for Use in Microbicide Studies Addendum 1 (Dated November 2007) to the DAIDS Table for Grading Adult and Pediatric Adverse Events, Corrected Version 2.1, July 2017, or satisfactory evaluation with no treatment required of Grade 1 or higher Pap result
At Screening and Enrollment, agrees not to participate in other research studies involving drugs, medical devices, vaginal or rectal products, or vaccines after the Screening Visit and for the duration of study participation

Who cannot join

Pregnant at Screening or Enrollment or plans to become pregnant during the study period
Note: A documented negative pregnancy test performed by study staff is required for inclusion; however, a self-reported pregnancy is adequate for exclusion from the study.
Diagnosed with symptomatic urinary tract infection (UTI) or reproductive tract infection (RTI) at Screening or Enrollment
Otherwise eligible participants diagnosed with UTI/RTI during screening will be offered treatment. If treatment is complete and symptoms have resolved within the 45 day screening window, eligible participants may be enrolled.
Note: Asymptomatic BV and candidiasis are not exclusionary.
Diagnosed with an acute sexually transmitted infection (STI) requiring treatment per current Centers for Disease Control and Prevention (CDC) guidelines (http://www.cdc.gov/std/treatment/) at Screening or Enrollment such as gonorrhea, chlamydia, trichomonas, pelvic inflammatory disease, and/or syphilis

Show all 28Show fewer

Note: Genital warts requiring treatment and frequent recurrence of HSV are considered exclusionary; however, infrequent HSV outbreaks are not. Genital warts requiring treatment are defined as those that cause undue burden or discomfort to the participant, including bulky size, unacceptable appearance, or physical discomfort. See MTN-038 Study-Specific Procedures (SSP) Manual for additional information.
Has a clinically apparent Grade 2 or higher pelvic exam finding (observed by study staff) at Screening or Enrollment. *
Note: Cervical bleeding associated with speculum insertion and/or specimen collection judged to be within the range of normal according to the clinical judgment of the IoR/designee is considered expected non-menstrual bleeding and is not exclusionary.
Note: Otherwise eligible participants with exclusionary pelvic exam findings may be enrolled/randomized after the findings have improved to a non-exclusionary severity grading or resolved within 45 days of providing informed consent for screening.
Participant report and/or clinical evidence of any of the following:
Known adverse reaction to any of the study products (ever), including polyurethane
Chronic and/or recurrent vaginal candidiasis
Non-therapeutic injection drug use in the 12 months prior to Enrollment
Last pregnancy outcome less than 90 days prior to Enrollment
Gynecologic or genital procedure (e.g., tubal ligation, dilation and curettage, piercing) 45 days or less prior to Enrollment
Note: Colposcopy and cervical biopsies for evaluation of an abnormal Pap test as well as IUD insertion/removal are not exclusionary.
Currently breastfeeding or planning to breastfeed during the study
Participation in any other research study involving drugs, medical devices, vaginal or rectal products, or vaccines, in the 60 days prior to Enrollment
Use of pre-exposure prophylaxis (PrEP) for HIV prevention and/or post-exposure prophylaxis (PEP) for potential HIV exposure within the 3 months prior to Enrollment, and/or anticipated use and/or unwillingness to abstain from PrEP during trial participation
Has any of the following laboratory abnormalities at Screening Visit:
Grade 1 or higher Aspartate aminotransferase (AST) or alanine transaminase (ALT)*
Grade 1 or higher Hemoglobin*
Calculated creatinine clearance less than 60 mL/min by the Cockcroft-Gault formula
Positive Hepatitis B surface antigen result
Note: Otherwise eligible participants with an exclusionary laboratory result may be re-tested during the screening process. If a participant is re-tested and a non-exclusionary result is documented within 45 days of providing informed consent for screening, the participant may be enrolled.
Has any other condition that, in the opinion of the IoR/designee, would preclude informed consent, make study participation unsafe, complicate the interpretation of study outcome data, or otherwise interfere with achieving the study objectives including any significant uncontrolled active or chronic medical condition.
() Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events Corrected Version 2.1, July 2017 and/or Addendum 1 (Female Genital Grading Table for Use in Microbicide Studies [Dated November 2007])

Trial locations and contacts

3 sites in 1 country.

United States3 sites

Alabama CRS
Birmingham, Alabama, 35294
University of Pittsburgh CRS
Pittsburgh, Pennsylvania, 15213
Bridge HIV CRS
San Francisco, California, 94143

Other trials in United States

About this study

Official title: A Phase 1, Randomized Pharmacokinetic and Safety Study of a 90 Day Intravaginal Ring Containing Tenofovir

The purpose of this study is to evaluate the pharmacokinetics (PK) and safety of a 90-day intravaginal ring (IVR) containing tenofovir (TFV).

Read the detailed description

This study will evaluate the pharmacokinetics (PK) and safety of a 90-day intravaginal ring (IVR) containing tenofovir (TFV) in healthy, HIV-uninfected individuals assigned female sex at birth.

Participants will be randomly assigned to receive an IVR containing either 1.4 g TFV or placebo. The IVR will be inserted at the enrollment visit (Day 0) and used continuously for approximately 91 days.

Additional study visits will occur at Days 1, 7, 14, 28, 42, 56, 91, and 92. Study visits may include behavioral assessments, physical examinations, blood and urine collection, and pelvic and rectal specimen collection.

Conditions: HIV Infections
Being tested: Tenofovir (TFV) IVR, Placebo IVR
Medical subject headings: HIV Infections

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Tenofovir (TFV) IVRDrug
Contains 1.4 g TFV
Placebo IVRDrug
Contains placebo

Study groups in NCT03670355
Study group	Role	What they receive
Tenofovir (TFV) Intravaginal Ring (IVR)	Experimental	The TFV IVR will be inserted during the enrollment visit (Day 0) and used continuously for approximately 91 days. Receives: Drug: Tenofovir (TFV) IVR
Placebo IVR	Placebo comparator	The placebo IVR will be inserted during the enrollment visit (Day 0) and used continuously for approximately 91 days. Receives: Drug: Placebo IVR

What is being measured

The primary outcome is the main question the study is designed to answer.

Measurement of TFV Levels in Plasma
TFV concentrations as assessed by drug detection testing in plasma samples collected at multiple timepoints during the study.
Measured: Measured through Day 92
Measurement of TFV Levels in Cervicovaginal Fluid (CVF)
TFV concentrations as assessed by drug detection testing in CVF samples collected at multiple timepoints during the study.
Measured: Measured through Day 92
Measurement of TFV Levels in Rectal Fluid
TFV concentrations as assessed by drug detection testing in rectal fluid samples collected at multiple timepoints during the study.
Measured: Measured through Day 92
Measurement of TFV Levels in Cervical Tissue
TFV concentrations as assessed by drug detection testing in cervical tissue samples collected at multiple timepoints during the study.
Measured: Measured through Day 92
Measurement of Tenofovir Diphosphate (TFV-DP) Levels in Cervical Tissue
TFV-DP concentrations as assessed by drug detection testing in cervical tissue samples collected at multiple timepoints during the study.
Measured: Measured through Day 92
Proportion of Participants With Grade 2 or Higher Genitourinary Adverse Event
As defined by the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Corrected Version 2.1, July 2017, and/or Addendum 1 (Female Genital [Dated November 2007] Grading Table for Use in Microbicide Studies)
Measured: Measured through Day 92
Proportion of Participants With Grade 3 or Higher Adverse Event
As defined by the DAIDS Table for Grading the Severity of Adult and Pediatric Adverse Events, Corrected Version 2.1, July 2017
Measured: Measured through Day 92

Secondary outcomes (3)

Number of Participants Fully Adherent to the Study IVR
Participants were classified as fully adherent if they kept the study ring inserted at all times during the 91 days of study product use, without any product hold (according to the Product Hold Log eCRF) or ever having the ring out (by self-report in the Ring Adherence eCRF). Ring outages could be ring removals or expulsions (voluntary or involuntary).
Measured: Measured through Day 92
Duration Without IVR in Vagina for Participants Not Fully Adherent
This includes only participants considered non-adherent. Participants were classified as fully adherent if they kept the study ring inserted at all times during the 91 days of study product use, without any product hold (according to the Product Hold Log eCRF) or ever having the ring out (by self-report in the Ring Adherence eCRF).
Measured: Measured through Day 92
Degree to Which Participants Like or Dislike Using the IVR
This outcome uses question J2 "Overall, how much do you like the ring?" from the final product use end visit (PUEV) behavioral questionnaire. This question and one timepoint were prespecified in the Statistical Analysis Plan (SAP) section 9.2 to represent the participants' overall acceptability of the study product. The question response is on a 10-point Likert scale from 1 to 10 with 1 being extremely dislike to 10 being extremely like. A Likert scale score of 5 is neutral.
Measured: Measured on the end of study, Day 92, visit.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

2 Jan 201925 Sep 2019

First posted13 Sep 2018
Study start2 Jan 2019
Primary completion25 Sep 2019
Study completion25 Sep 2019

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (2)Papers the sponsor has linked to this study.
Other trials for HIV InfectionsStudies of the same condition, open and under way.
More trials run by National Institute of Allergy and Infectious Diseases (NIAID)The sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 1
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind
Who is masked: Participant
Enrolment: 49 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT03670355
Sponsor's protocol ID: MTN-038
Other IDs: 38460
Status last verified: Oct 2025
First submitted: 12 Sep 2018
Last updated: 13 Nov 2025
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

Publications

Liu AY, Gundacker H, Richardson B, Chen BA, Hoesley C, van der Straten A, Brown A, Beamer M, Robinson J, Jacobson CE, Scheckter R, Bunge K, Schwartz J, Thurman A, Piper JM, Marzinke MA; MTN-038 Protocol Team for the Microbicide Trials Network. Phase 1 randomized pharmacokinetic and safety study of a 90-day tenofovir vaginal ring in the United States. J Int AIDS Soc. 2024 Mar;27(3):e26223. doi: 10.1002/jia2.26223.
PubMed 38444118
Hawley I, Song M, Scheckter R, McClure T, Piper J, Chen BA, Hoesley C, Liu AY, van der Straten A. Users' Preferred Characteristics of Vaginal Rings for HIV Prevention: A Qualitative Analysis of Two Phase I Trials. AIDS Res Hum Retroviruses. 2022 Apr;38(4):313-326. doi: 10.1089/AID.2021.0077. Epub 2022 Feb 11.
PubMed 34969254

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

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Study at a glance

From the registry record, last updated by the sponsor on 13 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Phase 1, Randomized Pharmacokinetic and Safety Study of a 90 Day Intravaginal Ring Containing Tenofovir
ClinicalTrials.gov ID: NCT03670355
Acronym / sponsor ID: MTN-038
Conditions: HIV Infections
Phase: Phase 1
Study type: Interventional
Recruitment status: Completed
Enrolment: 49 participants (actual)
Lead sponsor: National Institute of Allergy and Infectious Diseases (NIAID)US National Institutes of Health
Study start: 2 Jan 2019 (actual)
Primary completion: 25 Sep 2019 (actual)
Study completion: 25 Sep 2019 (actual)
First posted: 13 Sep 2018 (actual)
Results: Posted 13 Nov 2025

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

The purpose of this study is to evaluate the pharmacokinetics (PK) and safety of a 90-day intravaginal ring (IVR) containing tenofovir (TFV).

Detailed description

This study will evaluate the pharmacokinetics (PK) and safety of a 90-day intravaginal ring (IVR) containing tenofovir (TFV) in healthy, HIV-uninfected individuals assigned female sex at birth.

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind (participant)
Number of arms: 2

Arm	Type	Receives
Tenofovir (TFV) Intravaginal Ring (IVR)	Experimental	Drug: Tenofovir (TFV) IVRThe TFV IVR will be inserted during the enrollment visit (Day 0) and used continuously for approximately 91 days.
Placebo IVR	Placebo comparator	Drug: Placebo IVRThe placebo IVR will be inserted during the enrollment visit (Day 0) and used continuously for approximately 91 days.

Who may qualify

Ages: 18 to 45 years
Sex: Female only
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (23 listed)

Assigned female sex at birth
Age 18 through 45 years (inclusive) at Screening, verified per site standard operating procedures (SOPs)
Able and willing to provide written informed consent to be screened for and enrolled in MTN-038
Able and willing to provide adequate locator information, as defined in site SOPs
Able to communicate in spoken and written English

Key exclusion criteria (28 listed)

Pregnant at Screening or Enrollment or plans to become pregnant during the study period
Diagnosed with symptomatic urinary tract infection (UTI) or reproductive tract infection (RTI) at Screening or Enrollment
Diagnosed with an acute sexually transmitted infection (STI) requiring treatment per current Centers for Disease Control and Prevention (CDC) guidelines (http://www.cdc.gov/std/treatment/) at Screening or Enrollment such as gonorrhea, chlamydia, trichomonas, pelvic inflammatory disease, and/or syphilis
Has a clinically apparent Grade 2 or higher pelvic exam finding (observed by study staff) at Screening or Enrollment. *
Participant report and/or clinical evidence of any of the following:

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Tenofovir (TFV) IVRContains 1.4 g TFV	Drug	Tenofovir (TFV) Intravaginal Ring (IVR)
Placebo IVRContains placebo	Drug	Placebo IVR

Primary outcome

Measurement of TFV Levels in Plasma
Time frame: Measured through Day 92
TFV concentrations as assessed by drug detection testing in plasma samples collected at multiple timepoints during the study.
Measurement of TFV Levels in Cervicovaginal Fluid (CVF)
Time frame: Measured through Day 92
TFV concentrations as assessed by drug detection testing in CVF samples collected at multiple timepoints during the study.
Measurement of TFV Levels in Rectal Fluid
Time frame: Measured through Day 92
TFV concentrations as assessed by drug detection testing in rectal fluid samples collected at multiple timepoints during the study.
Measurement of TFV Levels in Cervical Tissue
Time frame: Measured through Day 92
TFV concentrations as assessed by drug detection testing in cervical tissue samples collected at multiple timepoints during the study.
Measurement of Tenofovir Diphosphate (TFV-DP) Levels in Cervical Tissue
Time frame: Measured through Day 92
TFV-DP concentrations as assessed by drug detection testing in cervical tissue samples collected at multiple timepoints during the study.
Proportion of Participants With Grade 2 or Higher Genitourinary Adverse Event
Time frame: Measured through Day 92
As defined by the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Corrected Version 2.1, July 2017, and/or Addendum 1 (Female Genital [Dated November 2007] Grading Table for Use in Microbicide Studies)
Proportion of Participants With Grade 3 or Higher Adverse Event
Time frame: Measured through Day 92
As defined by the DAIDS Table for Grading the Severity of Adult and Pediatric Adverse Events, Corrected Version 2.1, July 2017

3 secondary outcomes

Number of Participants Fully Adherent to the Study IVR
Time frame: Measured through Day 92
Duration Without IVR in Vagina for Participants Not Fully Adherent
Time frame: Measured through Day 92
Degree to Which Participants Like or Dislike Using the IVR
Time frame: Measured on the end of study, Day 92, visit.

Results and safety

Results posted to the registry on 13 Nov 2025, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Tenofovir (TFV) Intravaginal Ring (IVR)	33	32
Placebo IVR	16	14

Primary outcome: Measurement of TFV Levels in Plasma

Time frame: Measured through Day 92. Geometric mean (Geometric Coefficient of Variation). Unit: pg/mL

Measure	Tenofovir (TFV) Intravaginal Ring (IVR) n = 33
Day 1 postdosing	636.8 (131.2)
Day 7 postdosing	1915.9 (102.3)
Day 14 postdosing	3581.5 (114.7)
Day 28 postdosing	5040.7 (235.0)
Day 56 postdosing	7862.3 (139.6)
Day 91 postdosing	1814.6 (612.2)
Day 91, 4 hours post-removal	1081.2 (426.9)
Day 92, 24 hours post-removal	236.2 (127.4)

Primary outcome: Measurement of TFV Levels in Cervicovaginal Fluid (CVF)

Time frame: Measured through Day 92. Geometric mean (Geometric Coefficient of Variation). Unit: ng/mg

Measure	Tenofovir (TFV) Intravaginal Ring (IVR) n = 33
Day 0, Hour 1 postdosing	3 (95.3)
Day 0, Hour 4 postdosing	6.2 (92.6)
Day 1 postdosing	437.8 (75.1)
Day 7 postdosing	1468.2 (129.9)
Day 14 postdosing	2006.4 (57.2)
Day 28 postdosing	2011.8 (288.6)
Day 56 postdosing	2817.1 (70.8)
Day 91 postdosing	270.5 (24859.2)

Primary outcome: Measurement of TFV Levels in Rectal Fluid

Time frame: Measured through Day 92. Geometric mean (Geometric Coefficient of Variation). Unit: pg/mg

Measure	Tenofovir (TFV) Intravaginal Ring (IVR) n = 33
Day 1 postdosing	293.6 (1111.0)
Day 14 postdosing	701.8 (583.2)
Day 28 postdosing	898.3 (1355.9)
Day 56 postdosing	1377.3 (475.9)
Day 91 postdosing	460.3 (1093.3)
Day 91, 4 hours post-removal	416.7 (4315.6)

Primary outcome: Measurement of TFV Levels in Cervical Tissue

Time frame: Measured through Day 92. Geometric mean (Geometric Coefficient of Variation). Unit: ng/mg

Measure	Tenofovir (TFV) Intravaginal Ring (IVR) n = 32
Day 14 postdosing	45.9 (11800.2)
Day 28 postdosing	39.1 (322.8)
Day 56 postdosing	37.1 (177.1)
Day 91 postdosing	6.5 (254895.9)

Population analysed: This endpoint includes results from samples collected only from participants randomized to the TFV IVR arm. The samples from participants randomized to placebo will not have any TFV concentrations (outcome measure) in their cervical tissue. In addition, one participant on the TFV IVR arm declined collection of cervical tissue samples and is not included in the number analyzed.

3 secondary outcomes are reported in the full results.

Adverse events

Time frame: Participants are followed for adverse events during study follow-up which was scheduled up to 3 months (92 days) per participant. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Tenofovir (TFV) Intravaginal Ring (IVR)	0 of 33 (0%)	25 of 33 (75.8%)	0 of 33
Placebo IVR	0 of 16 (0%)	13 of 16 (81.3%)	0 of 16

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 13 Nov 2025.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Results publication: PubMed 38444118Liu AY, Gundacker H, Richardson B, Chen BA, Hoesley C, van der Straten A, Brown A, Beamer M, Robinson J, Jacobson CE, Scheckter R, Bunge K, Schwartz J, Thurman A, Piper JM, Marzinke MA; MTN-038 Protocol Team for the Microbicide Trials Network. Phase 1 randomized pharmacokinetic and safety study of a 90-day tenofovir vaginal ring in the United States. J Int AIDS Soc. 2024 Mar;27(3):e26223. doi: 10.1002/jia2.26223.
Derived from this study: PubMed 34969254Hawley I, Song M, Scheckter R, McClure T, Piper J, Chen BA, Hoesley C, Liu AY, van der Straten A. Users' Preferred Characteristics of Vaginal Rings for HIV Prevention: A Qualitative Analysis of Two Phase I Trials. AIDS Res Hum Retroviruses. 2022 Apr;38(4):313-326. doi: 10.1089/AID.2021.0077. Epub 2022 Feb 11.

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Albert Liu, MD, MPH study chair

San Francisco Department of Public Health

3 sites in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 1 study testing Tenofovir (TFV) IVR in people with HIV Infections, run by National Institute of Allergy and Infectious Diseases (NIAID) at 3 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 23 inclusion and 28 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 13 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 3 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 13 Nov 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Measurement of TFV Levels in Plasma (time frame: Measured through Day 92). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03670355, which also lists 2 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Nov 2025.