Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine and Department of Medicine, University of Cape Town, South Africa.
Division of Clinical Pharmacology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
AIDS Res Hum Retroviruses. 2022 Jun;38(6):455-462. doi: 10.1089/AID.2021.0135. Epub 2021 Dec 29.
The high cost of viral load (VL) testing limits its use for antiretroviral therapy (ART) adherence support. A low-cost lateral flow urine tenofovir (TFV) rapid assay predicts pre-exposure prophylaxis breakthroughs, but has not yet been investigated in HIV treatment. We therefore evaluated its utility in a pilot cross-sectional study of TFV-containing ART recipients at an increased risk of virologic failure (VF). Participants who had a treatment interruption ≥30 days or had ≥1 episode of viremia (VL ≥400 copies/mL) in the previous year were recruited from a public health setting in Cape Town, South Africa. Self-reported adherence data were collected, the urine TFV assay performed, and concurrent TFV-diphosphate analyzed in dried blood spots. VL testing was done concurrently and, if viremic, genotypic HIV drug resistance testing was performed. Of 48 participants, 18 (37.5%) had VL (>400 copies/mL) at the time of the study, including 16 of 39 receiving efavirenz (EFV), 2 of 6 receiving protease inhibitors, and 0 of 3 receiving dolutegravir. Resistance testing succeeded in 17/18, of which 14 had significant mutations compromising ≥2 agents of the current EFV-based regimen. Of these 14, all had detected urine TFV. Urine TFV was undetectable in two out of three without regimen-relevant resistance; = .02. In participants on EFV-based regimens returning to care, VF was largely due to viral resistance, where detectable urine TFV had 100% sensitivity (14/14 participants) in predicting resistance. Conversely, when undetectable, the urine-based assay could be used to preclude participants with poor adherence from undergoing costly HIV drug resistance testing.
病毒载量（VL）检测费用高昂，限制了其在抗逆转录病毒治疗（ART）依从性支持中的应用。一种低成本的侧向流动尿液替诺福韦（TFV）快速检测可预测暴露前预防突破，但尚未在 HIV 治疗中进行研究。因此，我们在南非开普敦的一个公共卫生环境中，对存在病毒学失败（VF）风险增加的接受 TFV 含 ART 的患者进行了一项试点横断面研究，评估了该检测的实用性。参与者在过去一年中治疗中断时间≥30 天或≥1 次病毒血症（VL≥400 拷贝/ml），他们是从一个公共卫生环境中招募的。收集了自我报告的依从性数据，进行了尿液 TFV 检测，并对干血斑中的 TFV-二磷酸进行了同时分析。同时进行了 VL 检测，如果病毒血症，则进行了基因型 HIV 耐药性检测。在 48 名参与者中，18 名（37.5%）在研究时 VL（>400 拷贝/ml），其中 16 名接受依非韦伦（EFV），6 名接受蛋白酶抑制剂，3 名接受多替拉韦。18 名中有 17 名成功进行了耐药性检测，其中 14 名有显著的耐药突变，使目前的 EFV 为基础的方案中的≥2 种药物受到影响。这 14 名中，所有都检测到尿液 TFV。没有方案相关耐药性的 3 名中有 2 名的尿液 TFV 未检出；=0.02。在返回治疗的接受 EFV 为基础方案的参与者中，VF 主要是由于病毒耐药性，在预测耐药性方面，可检测到尿液 TFV 的敏感性为 100%（14/14 名参与者）。相反，当不可检测时，尿液检测可用于排除依从性差的患者进行昂贵的 HIV 耐药性检测。
