Respiratory Viruses Unit, Virology Section, Microbiology Department, Vall d'Hebron Hospital Universitari, Vall d'Hebron Institut de Recerca, Vall d'Hebron Barcelona Hospital Campus, Passeig Vall d'Hebron, Barcelona, Spain; Centro de Instigación Biomédica en red de Enfermedades Infecciosas CIBERINFEC, Instituto Carlos III, Madrid, Spain.
Department of Hematology, Vall d'Hebron Hospital Universitari, Experimental Hematology, Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Hospital Campus, Passeig Vall d'Hebron, Barcelona, Spain.
Clin Microbiol Infect. 2023 Feb;29(2):240-246. doi: 10.1016/j.cmi.2022.08.021. Epub 2022 Sep 5.
To monitor the early emergence of genetic mutations related to reduced susceptibility to monoclonal anti-body (mAb)-based treatment in immunocompromised patients with long-term viral excretion using whole-genome sequencing at a tertiary university hospital in Barcelona, Spain.
Serial severe acute respiratory syndrome coronavirus 2-positive samples (mid-December 2021-mid-March 2022) from eight immunosuppressed, fully vaccinated patients (for solid-organ transplantation or haematologic malignancies) with long-term viral excretion despite undergoing mAb therapy (sotrovimab) for coronavirus disease 2019 were selected. Whole-genome sequencing was performed following the ARTIC, version 4.1, protocol on the MiSeq platform. Mutations in the coding sequence of the spike protein with a frequency of ≥5% were studied.
A total of 37 samples from the studied cases were analysed. All the cases, except one, were confirmed to have the Omicron variant BA.1; one had Delta (AY.100). Thirty-four different mutations were detected within the receptor-binding domain of the spike protein in 62.5% of patients, eight of which were not lineage related and located in the sotrovimab target epitope (P337L, E340D, E340R, E340K, E340V, E340Q, R346T and K356T). Except for P337L, all changes showed a significant increase in frequency or fixation after the administration of sotrovimab. Some of them have been associated with either reduced susceptibility to mAb therapy, such as those at position 340, or the acquisition of a new glycosylation site (346 and 356 positions).
This study highlights the importance of monitoring for early in vivo selection of mutations associated with reduced susceptibility to mAb therapy, especially in immunocompromised patients receiving anti-viral drugs, whose immune response is not able to control viral replication, resulting in long-term viral shedding, and those receiving selective evolution pressure. Virologic surveillance of genetically resistant viruses to available anti-viral therapies is considered a priority for both patients and the community.
在西班牙巴塞罗那的一家三级大学医院，使用全基因组测序，监测长期病毒排出的免疫功能低下的患者中与单抗（mAb）治疗敏感性降低相关的遗传突变的早期出现，这些患者接受了单抗治疗（索托维单抗）用于治疗 2019 冠状病毒病，但仍具有长期病毒排出。
选择了 8 例接受过实体器官移植或血液恶性肿瘤治疗的免疫抑制、完全接种疫苗但长期病毒排出的患者（中位 2021 年 12 月至 2022 年 3 月中旬）的连续严重急性呼吸综合征冠状病毒 2 阳性样本（sotrovimab）。根据 ARTIC，版本 4.1，在 MiSeq 平台上进行全基因组测序。研究了 Spike 蛋白编码序列中频率≥5%的突变。
对研究病例的 37 个样本进行了分析。除 1 例外，所有病例均证实为奥密克戎变异株 BA.1；1 例为德尔塔（AY.100）。在 Spike 蛋白受体结合域中检测到 34 种不同的突变，62.5%的患者中有 8 种突变与谱系无关，位于索托维单抗靶位（P337L、E340D、E340R、E340K、E340V、E340Q、R346T 和 K356T）。除 P337L 外，所有变化在使用索托维单抗后均显示出频率或固定性的显著增加。其中一些与 mAb 治疗敏感性降低有关，如位置 340 处的突变，或获得新的糖基化位点（346 和 356 位）。
本研究强调了监测与 mAb 治疗敏感性降低相关的突变早期体内选择的重要性，特别是在接受抗病毒药物治疗的免疫功能低下患者中，这些患者的免疫反应无法控制病毒复制，导致长期病毒排出，以及接受选择性进化压力的患者。对现有抗病毒治疗具有遗传耐药性的病毒进行病毒学监测被认为是患者和社区的首要任务。
