Trial Outcomes & Findings for LetSync: Pilot Test of Mobile Health (mHealth) Intervention (NCT NCT04951544)
NCT ID: NCT04951544
Last Updated: 2026-03-23
Results Overview
The investigators will use self-collected urine samples as another objective measure of drug adherence for participants living with HIV. The investigators will mail participants a urine sample collection kit with necessary supplies and detailed instructions via online demonstration video. Participants will self-collect and administer the urine sample and send a photo of the results to study staff. Urine test results were collected between baseline (T0) and 8 months (T4) as proportion of samples returned.
COMPLETED
NA
144 participants
8 months
2026-03-23
Participant Flow
Participants were recruited via social media (e.g., dating apps, Facebook, Twitter/X, Instagram), UCSF patient mailing, engagement of community-based organizations, study material distribution via email listservs, and word-of-mouth.
The sampling and analysis approaches differ: To be eligible, Index participants needed to enroll with their partner (i.e., Partner participants). For analyses, we do not separate by Index vs. Partner individuals because we do not analyze individuals as "Index" vs. "Partner", i.e., we include all individuals who provide the outcomes data of interest. Index participants could continue in the study if their partner discontinued.
Participant milestones
| Measure |
Intervention Arm
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Overall Study
STARTED
|
70
|
74
|
|
Overall Study
COMPLETED
|
62
|
72
|
|
Overall Study
NOT COMPLETED
|
8
|
2
|
Reasons for withdrawal
| Measure |
Intervention Arm
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Overall Study
Participant requested that their data be deleted from the study.
|
1
|
0
|
|
Overall Study
Lost to Follow-up
|
7
|
2
|
Baseline Characteristics
LetSync: Pilot Test of Mobile Health (mHealth) Intervention
Baseline characteristics by cohort
| Measure |
Total
n=143 Participants
Total of all reporting groups
|
Intervention Arm
n=69 Participants
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
The unit of randomization was the dyad, i.e., each dyad - not an individual - was randomized to either the intervention or control. We did not randomize by individual index or partner participant; we randomized by the dyad, i.e., the couple together. Each arm contained both members of each dyad.
|
Control Arm
n=74 Participants
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
The unit of randomization was the dyad, i.e., each dyad - not an individual - was randomized to either the intervention or control. We did not randomize by individual index or partner participant; we randomized by the dyad, i.e., the couple together. Each arm contained both members of each dyad.
|
|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=18 Participants
|
0 Participants
n=10 Participants
|
0 Participants
n=8 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
133 Participants
n=18 Participants
|
64 Participants
n=10 Participants
|
69 Participants
n=8 Participants
|
|
Age, Categorical
>=65 years
|
10 Participants
n=18 Participants
|
5 Participants
n=10 Participants
|
5 Participants
n=8 Participants
|
|
Sex/Gender, Customized
Male or man
|
128 Participants
n=18 Participants
|
64 Participants
n=10 Participants
|
64 Participants
n=8 Participants
|
|
Sex/Gender, Customized
Gender-minority
|
15 Participants
n=18 Participants
|
5 Participants
n=10 Participants
|
10 Participants
n=8 Participants
|
|
Race/Ethnicity, Customized
Non-white
|
120 Participants
n=18 Participants
|
60 Participants
n=10 Participants
|
60 Participants
n=8 Participants
|
|
Race/Ethnicity, Customized
White
|
23 Participants
n=18 Participants
|
9 Participants
n=10 Participants
|
14 Participants
n=8 Participants
|
PRIMARY outcome
Timeframe: 8 monthsPopulation: The sampling and analysis approaches differ: To be eligible, Index participants needed to enroll with their partner (i.e., Partner participants). However, for data analyses of the outcomes, we do not separate by Index vs. Partner individuals because we do not analyze individuals as "Index" vs. "Partner", i.e., we include all individuals who provide the outcomes data of interest. In this case, it is the Proportion of urine samples returned by anyone enrolled in the study.
The investigators will use self-collected urine samples as another objective measure of drug adherence for participants living with HIV. The investigators will mail participants a urine sample collection kit with necessary supplies and detailed instructions via online demonstration video. Participants will self-collect and administer the urine sample and send a photo of the results to study staff. Urine test results were collected between baseline (T0) and 8 months (T4) as proportion of samples returned.
Outcome measures
| Measure |
Intervention Arm
n=69 Participants
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
n=74 Participants
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Proportion of Urine Samples Returned by Participants
|
54 Participants
|
65 Participants
|
PRIMARY outcome
Timeframe: 8 monthsPopulation: The sampling and analysis approaches differ: To be eligible, Index participants needed to enroll with their partner (i.e., Partner participants). However, for data analyses of the outcomes, we do not separate by Index vs. Partner individuals because we do not analyze individuals as "Index" vs. "Partner", i.e., we include all individuals who provide the outcomes data of interest. In this case, it is the Levels of Antiretroviral (ARV, TFVDP) concentration in dried blood spot (DBS) samples.
The investigators will use the UNC Pharmacology Lab to analyze ARV levels in dried blood spot (DBS) samples as an objective measure of drug adherence and exposure for HIV-infected participants. The investigators will mail participants a DBS sample collection kit with necessary supplies, detailed instructions via online demonstration video, and a prepaid return envelope. DBS samples will be collected and analyzed between baseline (T0) and 8 months (T4). ARV levels of TFVDP will be measured as nanograms per milligram (ng/mg) of DBS will be log-transformed for data analysis. Changes since Baseline of ARV levels will be measured.
Outcome measures
| Measure |
Intervention Arm
n=54 Participants
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
n=59 Participants
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Levels of Antiretroviral (ARV, TFVDP) Concentration in Dried Blood Spot (DBS) Samples
|
485.03 ng/mg
Standard Deviation 603.42
|
595.55 ng/mg
Standard Deviation 1172.40
|
PRIMARY outcome
Timeframe: 8 monthsPopulation: The sampling and analysis approaches differ: To be eligible, Index participants needed to enroll with their partner (i.e., Partner participants). However, for data analyses of the outcomes, we do not separate by Index vs. Partner individuals because we do not analyze individuals as "Index" vs. "Partner", i.e., we include all individuals who provide the outcomes data of interest. In this case, it is the Self-reported measure of care engagement.
Self-reported care engagement will be measured with the 10-item Index of Engagement in HIV Care rated on a Likert-type scale ranging from 1 to 5, 'Strongly disagree' to 'Strongly agree'. The minimum summed score is 10, the maximum summed score is 50. A score will be calculated is the sum of all items without missing responses, with a higher score representing better care engagement and lower score representing worse care engagement.
Outcome measures
| Measure |
Intervention Arm
n=62 Participants
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
n=72 Participants
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Self-reported Measure of Care Engagement
|
31.2 score on a scale
Standard Deviation 4.38
|
36.5 score on a scale
Standard Deviation 6.04
|
SECONDARY outcome
Timeframe: 8 monthsPopulation: The sampling and analysis approaches differ: To be eligible, Index participants needed to enroll with their partner (i.e., Partner participants). However, for data analyses of the outcomes, we do not separate by Index vs. Partner individuals because we do not analyze individuals as "Index" vs. "Partner", i.e., we include all individuals who provide the outcomes data of interest. In this case, it is the Number of individual participants retained.
Between baseline (T0) and 8 months (T4), the investigators will collect feasibility-related data in terms of number of participants retained in the study from baseline to 8-month (T4) by condition. This is a feasibility and acceptability pilot trial, and one of the main outcomes is acceptability of the trial protocol and procedures, as indicated by participant retention rate, calculated as: The number of participants that remained in the trial divided by the total number of participants at the start of the trial.
Outcome measures
| Measure |
Intervention Arm
n=69 Participants
This is the Intervention Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Intervention Arm received the LetSync app to use through the 8-month trial.
|
Control Arm
n=74 Participants
This is the Control Arm of the LetSync Pilot Study to evaluate the feasibility and acceptability of the LetSync app intervention and associated protocols and procedures to inform a full-scale RCT. The Control Arm did not receive the LetSync app.
|
|---|---|---|
|
Number of Participants Retained
|
61 Participants
|
72 Participants
|
Adverse Events
Intervention Arm
Control Arm
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place