Service des Maladies Infectieuses et Tropicales, Hôpital Purpan, Toulouse, France.
PLoS One. 2011;6(6):e21655. doi: 10.1371/journal.pone.0021655. Epub 2011 Jun 27.
The impact of minor drug-resistant variants of the type 1 immunodeficiency virus (HIV-1) on the failure of antiretroviral therapy remains unclear. We have evaluated the importance of detecting minor populations of viruses resistant to non-nucleoside reverse-transcriptase inhibitors (NNRTI) during intermittent antiretroviral therapy, a high-risk context for the emergence of drug-resistant HIV-1. We carried out a longitudinal study on plasma samples taken from 21 patients given efavirenz and enrolled in the intermittent arm of the ANRS 106 trial. Allele-specific real-time PCR was used to detect and quantify minor K103N mutants during off-therapy periods. The concordance with ultra-deep pyrosequencing was assessed for 11 patients. The pharmacokinetics of efavirenz was assayed to determine whether its variability could influence the emergence of K103N mutants. Allele-specific real-time PCR detected K103N mutants in 15 of the 19 analyzable patients at the end of an off-therapy period while direct sequencing detected mutants in only 6 patients. The frequency of K103N mutants was <0.1% in 7 patients by allele-specific real-time PCR without further selection, and >0.1% in 8. It was 0.1%-10% in 6 of these 8 patients. The mutated virus populations of 4 of these 6 patients underwent further selection and treatment failed for 2 of them. The K103N mutant frequency was >10% in the remaining 2, treatment failed for one. The copy numbers of K103N variants quantified by allele-specific real-time PCR and ultra-deep pyrosequencing agreed closely (ρ = 0.89 P<0.0001). The half-life of efavirenz was higher (50.5 hours) in the 8 patients in whom K103N emerged (>0.1%) than in the 11 patients in whom it did not (32 hours) (P = 0.04). Thus ultrasensitive methods could prove more useful than direct sequencing for predicting treatment failure in some patients. However the presence of minor NNRTI-resistant viruses need not always result in virological escape.
ClinicalTrials.gov NCT00122551.
1 型免疫缺陷病毒（HIV-1）的少量耐药变异对抗逆转录病毒治疗失败的影响尚不清楚。我们评估了在间歇抗逆转录病毒治疗期间检测非核苷类逆转录酶抑制剂（NNRTI）耐药的少量病毒种群的重要性，这是 HIV-1 耐药出现的高危环境。我们对 21 名接受依非韦伦并参加 ANRS 106 试验间歇期的患者的血浆样本进行了纵向研究。等位基因特异性实时 PCR 用于检测和定量治疗中断期间的次要 K103N 突变体。对于 11 名患者，评估了与超高深度焦磷酸测序的一致性。测定依非韦伦的药代动力学，以确定其变异性是否会影响 K103N 突变体的出现。等位基因特异性实时 PCR 在 19 名可分析患者中的 15 名在治疗中断期末检测到 K103N 突变体，而直接测序仅在 6 名患者中检测到突变体。在没有进一步选择的情况下，通过等位基因特异性实时 PCR 检测到 7 名患者的 K103N 突变体频率 <0.1%，8 名患者中 >0.1%。在这 8 名患者中的 6 名中，K103N 突变体的频率为 0.1%-10%。其中 4 名患者的突变病毒群进一步选择，其中 2 名治疗失败。其余 2 名患者的 K103N 突变体频率 >10%，其中 1 名治疗失败。通过等位基因特异性实时 PCR 和超高深度焦磷酸测序定量的 K103N 变体的拷贝数密切一致（ρ=0.89 P<0.0001）。在 K103N 出现（>0.1%）的 8 名患者中，依非韦伦的半衰期（50.5 小时）高于未出现 K103N 的 11 名患者（32 小时）（P=0.04）。因此，超灵敏方法可能比直接测序更有助于预测某些患者的治疗失败。然而，少量 NNRTI 耐药病毒的存在并不总是导致病毒学逃逸。
ClinicalTrials.gov NCT00122551。
