GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, USA.
J Antimicrob Chemother. 2010 Feb;65(2):307-15. doi: 10.1093/jac/dkp419. Epub 2009 Dec 15.
HIV clonal genotypic analysis (CG) was used to investigate whether a more sensitive analysis method would detect additional low-abundance mutations compared with population genotyping (PG) in antiretroviral-naive patients who experienced virological failure (VF) during treatment with abacavir/lamivudine/zidovudine and tenofovir.
HIV was analysed by PG and CG (771 baseline and 657 VF clones) from subjects with VF (confirmed HIV RNA > or = 400 copies/mL at 24-48 weeks).
Fourteen of 123 subjects (11%) met VF criteria; their median baseline HIV RNA was 5.4 log(10) copies/mL, and 4.0 log(10) copies/mL at VF. By baseline PG, 2/14 had HIV-1 with nucleoside reverse transcriptase inhibitor (NRTI) or non-NRTI mutations. By baseline CG, 9/14 had HIV-1 with NNRTI and/or NRTI mutations; 7/9 had study drug-associated mutations. By PG at VF, 10/14 had selected for resistance mutations [2, K65R; 1, M184V; and 7, thymidine analogue mutations (TAMs) +/- M184V]. By CG at VF, for subjects with TAMs, T215F was more commonly detected (5/14 samples) than T215Y (2/14). For one subject who selected K65R at VF, both K65R-containing clones and TAM-containing clones (both T215A and T215F) were observed independently but not conjunctively in the same clone in a post-VF sample.
The majority of subjects with VF had major and minor mutations detected at VF; CG detected additional low-abundance variants at baseline and VF that could have influenced mutation selection pathways. Both PG and CG data suggest TAMs, not K65R selection, are the preferred resistance route, biased towards 215F selection. No HIV clone contained both K65R and T215F/Y mutations, suggesting in vivo antagonism between the two mutations. The once-daily zidovudine usage and high baseline viraemia may also have contributed to rapid selection of HIV with multiple mutations in VFs.
对接受阿巴卡韦/拉米夫定/齐多夫定和替诺福韦治疗后发生病毒学失败（VF）的初治患者，采用克隆基因型分析（CG）检测是否比群体基因型分析（PG）能更敏感地检测到更多低丰度突变。
对发生 VF（24-48 周时 HIV RNA>400 拷贝/ml）的患者，用 PG 和 CG（771 个基线和 657 个 VF 克隆）分析 HIV。
123 例患者中有 14 例（11%）符合 VF 标准；他们的基线 HIV RNA 中位数为 5.4log10 拷贝/ml，VF 时为 4.0log10 拷贝/ml。PG 基线时，14 例中有 2 例（14%）HIV-1 具有核苷逆转录酶抑制剂（NRTI）或非 NRTI 突变。CG 基线时，14 例中有 9 例（64%）HIV-1 具有 NNRTI 和/或 NRTI 突变；7 例有研究药物相关突变。PG 在 VF 时，14 例中有 10 例（71%）选择了耐药突变[2 例 K65R；1 例 M184V；7 例胸腺嘧啶类似物突变（TAMs）+/-M184V]。CG 在 VF 时，对于有 TAMs 的患者，更常检测到 T215F（14 个样本中有 5 个）而非 T215Y（14 个样本中有 2 个）。对 VF 时选择 K65R 的 1 例患者，在 VF 后样本中，单独而非共同地在同一克隆中观察到了含有 K65R 的克隆和含有 TAMs（T215A 和 T215F）的克隆。
VF 患者多数有 VF 时检测到的主要和次要突变；CG 在基线和 VF 时检测到了更多低丰度变异，这些变异可能影响了突变选择途径。PG 和 CG 数据均表明，TAMs 而非 K65R 选择是首选耐药途径，偏向于 215F 选择。没有 HIV 克隆同时含有 K65R 和 T215F/Y 突变，提示这两种突变在体内存在拮抗作用。每日一次齐多夫定的使用和高基线病毒血症可能也促成了 VF 中 HIV 多种突变的快速选择。
