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Use of Antiretroviral (ARV) Drug Levels in Dried Blood Spots (DBS) to Assess and Manage ART Adherence in South Africa

Use of ARV Drug Levels in Dried Blood Spots to Assess and Manage ART Adherence in South Africa

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04333498
Acronym
ADD-ART
Enrollment
60
Registered
2020-04-03
Start date
2020-09-18
Completion date
2022-11-29
Last updated
2023-01-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Therapeutic Adherence and Compliance

Brief summary

This is a prospective, pilot study of HIV-positive individuals who have been on tenofovir-containing antiretroviral therapy for at least 4 months. The overall goal of this research is to determine the feasibility of giving patients and their providers monthly feedback about Tenofovir-Diphosphate (TFV-DP) drug levels and to examine patient and provider behaviors in response to receiving this information. This study will build upon the Aim 1 observational study and the subsequent patient and providerFeedback Development Workgroups (FDWs).

Detailed description

This is a prospective, pilot study of HIV-positive individuals who have been on tenofovir-containing antiretroviral therapy for at least 4 months. The overall goal of this research is to determine the feasibility of giving patients and their providers monthly feedback about Tenofovir-Diphosphate (TFV-DP) drug levels and to examine patient and provider behaviors in response to receiving this information. This study will build upon the Aim 1 observational study and the subsequent patient and provider Feedback Development Workgroups (FDWs). The study team will consent a sample (N=60) of HIV-positive patients for monthly assessments, including blood specimen collections to assess TFV-DP drug levels. Participants enrolled in this prospective, pilot study will be randomized to either the intervention arm in which they will receive monthly feedback on their TFV-DP drug levels (Feedback Group; N=30) or the control arm in which they will receive no feedback on TFV-DP drug levels (No Feedback Group; N=30). The study will take place at the Gugulethu Research Offices (GRO) of the Desmond Tutu HIV Foundation (DTHF) in Gugulethu, 15km outside Cape Town, South Africa (SA). Study participants will be recruited from patients attending one of four public-sector ART clinics in the Klipfontein Health District, Western Cape, including (1) Hannan Crusaid Treatment Centre, (2) Nyanga Clinic, (3) Gugulethu Clinic (NY1), and (4) Vuyani Clinic. Enrollment will occur over 3-4 months, during which study staff will recruit an average of 15-20 participants per month, for a total of 60 participants. Participants will remain in the study for 5 months, attending a baseline and 4 subsequent monthly study visits. At each monthly visit, study staff will obtain venous blood samples for dried blood spots (DBS) which will measure TFV-DP levels and a viral load (VL) assay. ART adherence will also be assessed through the Wise Pill electronic monitoring device (EMD) a medication dispenser that sends an electronic medication event record to the Wisepill server when medication is taken and monthly self-reported medication adherence. Socio-demographic characteristics, medical history, mental health, substance use, and other contextual factors will be assessed at baseline and at the final study visit. In addition, at each visit, participants randomized to the intervention arm will receive feedback on their previous month's TFV-DP drug levels. Clinic providers will also receive TFV-DP drug level results for the participants in the intervention arm. For both intervention and control groups, the study will monitor any changes to ART adherence behavior on the part of patients and providers. Potential changes will be monitored by reviewing participants' clinic charts to determine if any actions were made to the medical or adherence management of patients since the previous visit (e.g., additional VL requests beyond those prescribed for a stable patient, referral for intensive counselor-based or group adherence counseling, outreach by Health Care Workers (HCWs) for adherence monitoring and support, additional doctor-requested patient appointments). The study will also conduct Exit Interviews with participants and hold Provider Focus Group Discussions (FGD) to further understand whether (and if so, how) TFV-DP drug level feedback influenced medication adherence and patient management.

Interventions

BEHAVIORALFeedback on DBS Concentrations

The study team will examine the feasibility and acceptability of a feedback system based on DBS concentration amounts.

Sponsors

Research Foundation for Mental Hygiene, Inc.
CollaboratorOTHER
Desmond Tutu HIV Foundation
CollaboratorOTHER
University of Cape Town
CollaboratorOTHER
University of Colorado, Denver
CollaboratorOTHER
National Institute of Allergy and Infectious Diseases (NIAID)
CollaboratorNIH
New York State Psychiatric Institute
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SUPPORTIVE_CARE
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 18 years of age or older * HIV-positive * Initiated ARV's containing tenofovir 4 or more months ago * Speaks English or Xhosa * Willing to attend 5 study visits approximately one month apart * Willing to allow the study team to contact his/her HIV care provider about his/her monthly TFV-diphosphate (TFV-DP) drug level * Willing to use Wise Pill to dispense ARVs for 4 months * Willing to receive text/short message service (SMS) and/or phone call reminders to charge the Wise Pill * Willing to allow the study team access to their medical chart/clinic folder

Exclusion criteria

* Unable to provide informed consent * Unwilling to participate in study procedures * Unwilling to allow the study team to contact his/her HIV care provider about his/her monthly TFV-DP drug level * Any condition that, in the opinion of the principal investigator would make participation in the study unsafe, complicated interpretation of study outcome data, or otherwise interfere with achieving the study objectives.

Design outcomes

Primary

MeasureTime frameDescription
TFV-diphosphate (TFV-DP) Drug Level5 MonthsTenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is used as a biomarker of antiretroviral therapy (ART) adherence. Recent treatment studies have shown that TFV-DP predicts future viremia in persons with HIV (PWH). Whole blood for DBS was collected at each study visit by venipuncture. To prepare the DBS, 25 mcl of whole blood were spotted five times onto a Whatman 903 ProteinSaver card and dried for a minimum of 3hrs and up to overnight before being individually packaged in a plastic bag with dessicant and a humidity indicator.
Viral Load (VL) Assay5 months
Electronic Adherence (EA) Percentages5 monthsThe number of days recorded as intake on electronic medical device (EMD) divided by days on study

Countries

South Africa, United States

Participant flow

Recruitment details

60 people with HIV (PWH) were recruited from an ART clinic in Cape Town. Recruitment commenced in 09/2020 and ended 02/2021.

Pre-assignment details

No pre-assignment details to note, all participants were randomized on the day they were enrolled.

Participants by arm

ArmCount
Receiving Feedback From TFV-DP Drug Levels Through DBS
This arm of participants will receive monthly feedback from medical providers on their adherence measured through DBS.
30
No Feedback
This arm of participants will not receive monthly feedback through TFV-DP levels in DBS.
30
Total60

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyLost to Follow-up10

Baseline characteristics

CharacteristicTotalReceiving Feedback From TFV-DP Drug Levels Through DBSNo Feedback
Age, Continuous39 years37 years41 years
Baseline TFV-DP Result1087 fmol/punch
STANDARD_DEVIATION 677
1163 fmol/punch
STANDARD_DEVIATION 856
1011 fmol/punch
STANDARD_DEVIATION 433
Hematocrit32 % of red blood cells33 % of red blood cells32 % of red blood cells
Months on ART56 Months68 Months52 Months
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
60 Participants30 Participants30 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
0 Participants0 Participants0 Participants
Region of Enrollment
South Africa
60 participants30 participants30 participants
Sex: Female, Male
Female
51 Participants25 Participants26 Participants
Sex: Female, Male
Male
9 Participants5 Participants4 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 300 / 30
other
Total, other adverse events
0 / 300 / 30
serious
Total, serious adverse events
0 / 300 / 30

Outcome results

Primary

Electronic Adherence (EA) Percentages

The number of days recorded as intake on electronic medical device (EMD) divided by days on study

Time frame: 5 months

ArmMeasureValue (MEAN)Dispersion
Receiving Feedback From TFV-DP Drug Levels Through DBSElectronic Adherence (EA) Percentages81 Percentage of days recorded as intakeStandard Deviation 21
No FeedbackElectronic Adherence (EA) Percentages79 Percentage of days recorded as intakeStandard Deviation 22
Comparison: Adherence percentagep-value: 0.21895% CI: [-8.614, 3.391]t-test, 2 sided
p-value: 0.27295% CI: [-0.036, 0.128]Regression, Linear
Primary

TFV-diphosphate (TFV-DP) Drug Level

Tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is used as a biomarker of antiretroviral therapy (ART) adherence. Recent treatment studies have shown that TFV-DP predicts future viremia in persons with HIV (PWH). Whole blood for DBS was collected at each study visit by venipuncture. To prepare the DBS, 25 mcl of whole blood were spotted five times onto a Whatman 903 ProteinSaver card and dried for a minimum of 3hrs and up to overnight before being individually packaged in a plastic bag with dessicant and a humidity indicator.

Time frame: 5 Months

ArmMeasureValue (MEAN)Dispersion
Receiving Feedback From TFV-DP Drug Levels Through DBSTFV-diphosphate (TFV-DP) Drug Level1377.82 fentomole/punchStandard Deviation 846.45
No FeedbackTFV-diphosphate (TFV-DP) Drug Level1156.79 fentomole/punchStandard Deviation 653.99
p-value: 0.01495% CI: [-396.33, -45.73]t-test, 2 sided
Primary

Viral Load (VL) Assay

Time frame: 5 months

ArmMeasureValue (MEAN)Dispersion
Receiving Feedback From TFV-DP Drug Levels Through DBSViral Load (VL) Assay67.07 copies/mlStandard Deviation 622.12
No FeedbackViral Load (VL) Assay1170.17 copies/mlStandard Deviation 8450.75
p-value: 0.12295% CI: [-296.532, 2502.722]t-test, 2 sided

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026