Department of Medicine, Infectious Diseases and Global Public Health, University of California San Diego, San Diego, California, United States of America.
Department of Pharmacy, University of California San Diego, La Jolla, California, United States of America.
PLoS One. 2023 Apr 27;18(4):e0275356. doi: 10.1371/journal.pone.0275356. eCollection 2023.
Pre-exposure prophylaxis for COVID-19 with tixagevimab/cilgavimab (T/C) received Emergency Use Authorization (EUA) based on results of a clinical trial conducted prior to the emergence of the Omicron variant. The clinical effectiveness of T/C has not been well described in the Omicron era. We examined the incidence of symptomatic illness and hospitalizations among T/C recipients when Omicron accounted for virtually all local cases.
Through retrospective electronic medical record chart review, we identified patients who received T/C between January 1 -July 31, 2022 within our quaternary referral health system. We determined the incidence of symptomatic COVID-19 infections and hospitalizations due to or presumed to be caused by early Omicron variants before and after receiving T/C (pre-T/C and post-T/C). Chi square and Mann-Whitney Wilcoxon two-sample tests were used to examine differences between the characteristics of those who got COVID-19 before or after T/C prophylaxis, and rate ratios (RR) and 95% confidence intervals (CI) were calculated to assess differences in hospitalization rates for the two groups.
Of 1295 T/C recipients, 105 (8.1%) developed symptomatic COVID-19 infection before receiving T/C, and 102 (7.9%) developed symptomatic disease after receiving it. Of the 105 patients who developed symptomatic infection pre-T/C, 26 (24.8%) were hospitalized, compared with six of the 102 patients (5.9%) who were diagnosed with COVID-19 post-T/C (RR = 0.24; 95% CI = 0.10-0.55; p = 0.0002). Seven of the 105 (6.7%) patients infected pre-T/C, but none of the 102 infected post-T/C required ICU care. No COVID-related deaths occurred in either group. The majority of COVID-19 cases among those infected pre-T/C treatment occurred during the Omicron BA.1 surge, while the majority of post-T/C cases occurred when Omicron BA.5 was predominant. In both groups, having at least one dose of vaccine strongly protected against hospitalization (pre-T/C group RR = 0.31, 95% CI = 0.17-0.57, p = 0.02; post-T/C group RR = 0.15; 95% CI = 0.03-0.94; p = 0.04).
We identified COVID-19 infections after T/C prophylaxis. Among patients who received T/C at our institution, COVID-19 Omicron cases occurring after T/C were one-fourth as likely to require hospitalization compared to those with Omicron prior to T/C. However, due to the presence of changing vaccine coverage, multiple therapies, and changing variants, the effectiveness of T/C in the Omicron era remains difficult to assess.
特敏福（tixagevimab/cilgavimab，T/C）用于 COVID-19 的暴露前预防，在 Omicron 变体出现之前的临床试验结果基础上获得了紧急使用授权（EUA）。在 Omicron 时代，T/C 的临床效果尚未得到很好的描述。我们研究了当 Omicron 变体几乎完全成为当地所有病例时，T/C 接受者出现有症状疾病和住院的情况。
通过回顾性电子病历图表审查，我们确定了在我们的四级转诊健康系统中，2022 年 1 月 1 日至 7 月 31 日期间接受 T/C 的患者。我们确定了在接受 T/C 之前和之后（T/C 前和 T/C 后）因早期 Omicron 变体或疑似由其引起的有症状 COVID-19 感染和住院的发生率。卡方和曼-惠特尼 Wilcoxon 两样本检验用于检查在 T/C 预防之前或之后感染 COVID-19 的患者特征之间的差异，并且计算率比（RR）和 95%置信区间（CI）以评估两组住院率的差异。
在 1295 名 T/C 接受者中，有 105 名（8.1%）在接受 T/C 之前出现有症状的 COVID-19 感染，有 102 名（7.9%）在接受 T/C 之后出现有症状的疾病。在 105 名 T/C 前出现有症状感染的患者中，有 26 名（24.8%）住院，而在 102 名 T/C 后诊断为 COVID-19 的患者中，有 6 名（5.9%）住院（RR = 0.24；95%CI = 0.10-0.55；p = 0.0002）。在 T/C 前感染的 105 名患者中，有 7 名（6.7%）需要 ICU 护理，而在 T/C 后感染的患者中没有。两组均未发生与 COVID 相关的死亡。在 T/C 前感染的患者中，大多数 COVID-19 病例发生在 Omicron BA.1 激增期间，而 T/C 后感染的大多数病例发生在 Omicron BA.5 为主时。在两组中，至少接种一剂疫苗可强烈预防住院（T/C 前组 RR = 0.31，95%CI = 0.17-0.57，p = 0.02；T/C 后组 RR = 0.15；95%CI = 0.03-0.94；p = 0.04）。
我们发现了 T/C 预防后的 COVID-19 感染。在我们机构接受 T/C 的患者中，与 T/C 前发生的 Omicron 病例相比，T/C 后发生的 Omicron 病例需要住院治疗的可能性降低了四分之一。然而，由于疫苗接种覆盖率、多种疗法和不断变化的变体的存在，T/C 在 Omicron 时代的有效性仍然难以评估。
