Evidence map›Paper›PMID 33742745›Full record

ArticleDrug testing and analysis2021

Tenofovir and emtricitabine concentrations in hair are comparable between individuals on tenofovir disoproxil fumarate versus tenofovir alafenamide-based ART.

Hideaki Okochi, Alexander Louie, Nhi Phung, Kevin Zhang, Regina M Tallerico, Karen Kuncze, Matthew A Spinelli, Catherine A Koss, Leslie Z Benet, Monica Gandhi

Open access · greenAbstract readComparative StudyValidation Study
PubMed Full text at PMC Publisher
In one paragraph

Article in Drug testing and analysis, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
1.0field-weighted citation impact, top 29% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed, 9 citations in OpenAlex.

  1. Point-of-Care Urine Tenofovir Drug-Level Feedback Counseling Improves Long-Term Pre-exposure Prophylaxis Adherence for US Men Who Have Sex With Men in Pilot RCT.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026
    Trial
  2. Trial
  3. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 1 institution in 1 country.

Hideaki OkochiDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.ORCID https://orcid.org/0000-0002-8519-7409
Alexander LouieDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Nhi PhungDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Kevin ZhangDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Regina M TallericoDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Karen KunczeDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Matthew A SpinelliDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Catherine A KossDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
Leslie Z BenetUCSF-Hair Analytical Laboratory, University of California San Francisco, San Francisco, California, USA.
Monica GandhiDivision of HIV, Infection Diseases, and Global Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.ORCID https://orcid.org/0000-0002-7025-1994
University of California, San Francisco · US

Funding

Virology CoreP30AI027763 · NIAID · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI STEVEN Grant DEEKS · 1988 to 2026
$93.6M
Plugging Hair ARV Levels as Adherence Biomarkers into HIV Prevention TrialsR01AI098472 · NIAID · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI GANDHI, MONICA · 2012 to 2021
$5.6M
PrEP Point-of-Care Brief-Intervention for Adherence among Young Men Who Have Sex with Men (PrEP2-BAY Study)K23MH122286 · NIMH · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI SPINELLI, MATTHEW A. · 2020 to 2024
$1.0M
Optimizing Adherence to PrEP among Young African Women through a Community Adherence Club InterventionK23MH114760 · NIMH · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI KOSS, CATHERINE ANNE STIMETS · 2018 to 2021
$796k
Objective measures of adherence for later-stage ART failure in resource limited settingsR03AI152773 · NIAID · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI GANDHI, MONICA · 2020 to 2021
$161k
NIAID NIH HHS R01 AI098472NIAID NIH HHS R03 AI152773NIMH NIH HHS K23 MH114760NIMH NIH HHS K23 MH122286
6 · The paper itself

Abstract

Tenofovir disoproxil fumarate (TDF) in combination with emtricitabine (FTC) is the backbone for both human immunodeficiency virus (HIV) treatment and pre-exposure prophylaxis (PrEP) worldwide. Tenofovir alafenamide (TAF) with FTC is increasingly used in HIV treatment and was recently approved for PrEP among men-who-have-sex-with-men. TDF and TAF are both metabolized into tenofovir (TFV). Antiretrovirals in plasma are taken up into hair over time, with hair levels providing a long-term measure of adherence. Here, we report a simple, robust, highly sensitive, and validated high-performance liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS)-based analytical method for analyzing TFV and FTC from individuals on either TDF/FTC or TAF/FTC in small hair samples. TFV/FTC are extracted from ~5 mg hair and separated on a column using a gradient elution. The lower quantification limits are 0.00200 (TFV) and 0.0200 (FTC) ng/mg hair; the assay is linear up to 0.400 (TFV) and 4.00 (FTC) ng/mg hair. The intra-day and inter-day coefficients of variance (CVs) are 5.39-12.6% and 6.40-13.5% for TFV and 0.571-2.45% and 2.45-5.16% for FTC. TFV concentrations from participants on TDF/FTC-based regimens with undetectable plasma HIV RNA were 0.0525 ± 0.0295 ng/mg, whereas those from individuals on TAF/FTC-based regimens were 0.0426 ± 0.0246 ng/mg. Despite the dose of TFV in TDF being 10 times that of TAF, hair concentrations of TFV were not significantly different for those on TDF versus TAF regimens. Pharmacological enhancers (ritonavir and cobicistat) did not boost TFV concentrations in hair. In summary, we developed and validated a sensitive analytical method to analyze TFV and FTC in hair and found that hair concentrations of TFV were essentially equivalent among those on TDF and TAF.

Indexed as

AdenineAnti-HIV AgentsChromatography, High Pressure LiquidCobicistatDose-Response Relationship, DrugEmtricitabineEmtricitabine, Tenofovir Disoproxil Fumarate Drug CombinationHairHair AnalysisHIV InfectionsHumansRitonavirTandem Mass SpectrometryTenofovirTissue DistributionAdenineAnti-HIV AgentsCobicistatEmtricitabineemtricitabine tenofovir alafenamideEmtricitabine, Tenofovir Disoproxil Fumarate Drug CombinationRitonavirTenofoviremtricitabine (FTC)hair concentrationstenofovir alafenamide (TAF)tenofovir disoproxil fumarate (TDF)tenofovir (TFV)

Identifiers

PMID33742745
PMCPMC9131373
OpenAlexW3139066086

What OpenQuestion holds

Textmetadata
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Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.